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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#41
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On Thu, 9 Feb 2012 08:14:31 +0000, Ian Jackson
wrote: In message , Jeff Liebermann writes Something is wrong. The nominal signal from the cable drop is suppose to be 0dBm. If there's a splitter involved, they like to crank it up to about 10dBm. Careful! Don't get your dBm mixed up with your dBmV. There's around 48dB difference! 0dBm is a massive 48dBmV. That would certainly make most set-top boxes wake up and pay attention! Oops. All my mentions of dBm should be dBmV. Thanks. Range of acceptable signal levels. They're similar for DTV. http://www.dslreports.com/faq/16085 How to check signal levels with a Motorola set top box: http://www.ehow.com/how_12186368_check-signal-strength-comcast-digital-cable-motorola.html -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#42
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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On Feb 8, 2:00*pm, amdx wrote:
Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap.. * That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. * *I don't has access to electricity at the utility post, so an amp is out. Although I could try an amp at the cable box end. Is that reasonable? I would run two cables if there was a way to make it increase signal strength. * Getting anymore from the cable company is not an option. * *Any ideas to get a better signal? * * * * * * * * Mikek PS. * When the signal fails it seems channel 41 is ok and above 42 it breaks up. Curious to know if there is an unusual frequency jump between those two digital channels. Google your cable box model. You should able to find ifo on how to pull up a menu that shows signal strengh. -60dbm is about where my sigal starts droping out Jimmie |
#43
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Posted to sci.electronics.repair
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![]() Jeff Urban wrote: All the technical advice is fine. However none of this is necessary. Just call the cable company and tell them that the situation is unacceptable so you are cancelling. Voila ! Next day dBs ! There are no dBs, since 'dB' without a reference level is meaningless. You'll have a whole lot less than 0 dBm. We would terminate service to people like that, because they were never satisfied. Out drops were at +10 dBm at the street. I had to sign a waiver to get cable service restored here, after a hurricane ripped down the original drop. they refused to replace it over a driveway, and the new route added +100 feet of RG-6 it runs along a fence line, to my garage. This was already 45 feet longer than the original drop. Then it ran 10' up the wall, 40' across the garage, 10' down the opposite wall and 40 feet of underground conduit back to where the original drop entered their weatherproof wiring box. -- You can't have a sense of humor, if you have no sense. |
#44
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() amdx wrote: On 2/8/2012 7:50 PM, Joerg wrote: Where does the other leg of that splitter go to? And is that end properly terminated? They go to two other outlets, that are used for transient boaters. sometimes they are used and sometimes they sit unterminated. I have not seen my problem better or worse when boats are in or out. But I have several 75 ohm F connector terminations. It's worth a try. Not really. If there are long unterminated 75 ohm cables after the splitter, they are a crude termination. The splitter's backmatch eliminates ghosting from reflections from the unterminated end. -- You can't have a sense of humor, if you have no sense. |
#45
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() Michael Coslo wrote: I don't know exactly how it's done now, but when I worked in the Cable industry many moons ago, we had a lot of adjustment we could make. Even more, we had variable by frequency attenuators so we could ensure that a flat signal showed up. Those are 'Equalizers' and used to cancel the cable losses. There is some adjustment in the trunk amplifiers, but some brands just used a plug in equalizer marked with the rolloff in dB while others had both. The coarse plugin, and a variable equalizer to level the trunkline for 'Proof of Performance' tests. -- You can't have a sense of humor, if you have no sense. |
#46
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() Joerg wrote: amdx wrote: Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. Looks like the cable guys screwed up. In your opinion. If they are delivering the level called for in their franchise, they didn't screw up. It has always been up to the customer to pay for or provide extra equipment for non standard installs. -- You can't have a sense of humor, if you have no sense. |
#47
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() Robert Baer wrote: amdx wrote: Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. I don't has access to electricity at the utility post, so an amp is out. Although I could try an amp at the cable box end. Is that reasonable? I would run two cables if there was a way to make it increase signal strength. Getting anymore from the cable company is not an option. Any ideas to get a better signal? Mikek PS. When the signal fails it seems channel 41 is ok and above 42 it breaks up. Curious to know if there is an unusual frequency jump between those two digital channels. Well, you could add an amplifier at the splitter where (nominally) there is no power. Use the coax center conductor for power; inline capacitors allow signal to pass and feeding center via small choke allows DC but no signal. Once upon a time there were little adapters that did this AC/DC thing... A power inserter is used to put 9-28 volts DC on the coax, depending on the amplifer you use. -- You can't have a sense of humor, if you have no sense. |
#48
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() "JIMMIE" wrote in message ... On Feb 8, 2:00 pm, amdx wrote: Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. I don't has access to electricity at the utility post, so an amp is out. Although I could try an amp at the cable box end. Is that reasonable? I would run two cables if there was a way to make it increase signal strength. Getting anymore from the cable company is not an option. Any ideas to get a better signal? Mikek PS. When the signal fails it seems channel 41 is ok and above 42 it breaks up. Curious to know if there is an unusual frequency jump between those two digital channels. Google your cable box model. You should able to find ifo on how to pull up a menu that shows signal strengh. -60dbm is about where my sigal starts droping out Jimmie ================================================== === Yes, but be mindful of the difference between dBm and dBmV. The cable industry often deals in levels on the dBmV scale. There are places like this ... http://www.maxim-ic.com/app-notes/index.mvp/id/808 where you can see some conversion equations. Jimmie's -60dBm equals -11.25 dBmV. Same power level -- different scale. I have long known level requirements for the TV tuner's cousin, the cable modem. The common DOCSIS 2 cable modems are usually spec'ed for -15dBmV to +15dBmV and the smart operators try to keep inside +/- 12. Thus, you can see that Jimmie's -11.25dBmV is near the low limit and that dropouts become more likely in that neighborhood. I little bit of google snooping revealed that DTV cable boxes would like 0dBmV and will usually be okay with -10dBmV to +10dBmV. Almost the same. i hope this helps. "Sal" "Sal" |
#49
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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Michael A. Terrell wrote:
Joerg wrote: amdx wrote: Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. Looks like the cable guys screwed up. In your opinion. If their company cable box doesn't deliver a useful and reliable signal I call that screwed up. One pays for a service and expects to either get it delivered as promised or money back. ... If they are delivering the level called for in their franchise, they didn't screw up. It has always been up to the customer to pay for or provide extra equipment for non standard installs. Mike's install does not sound non-standard. 170ft cable drop towards premises which is fairly normal, plus the cable company's set-top box. -- Regards, Joerg http://www.analogconsultants.com/ |
#50
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() Joerg wrote: Michael A. Terrell wrote: Joerg wrote: amdx wrote: Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. Looks like the cable guys screwed up. In your opinion. If their company cable box doesn't deliver a useful and reliable signal I call that screwed up. One pays for a service and expects to either get it delivered as promised or money back. ... If they are delivering the level called for in their franchise, they didn't screw up. It has always been up to the customer to pay for or provide extra equipment for non standard installs. Mike's install does not sound non-standard. 170ft cable drop towards premises which is fairly normal, plus the cable company's set-top box. Grow up. That is an excessive length drop. A standard drop is under 100 feet. You think you know everything, and that the world has to live by your rules. You don't, and it doesn't. I'll bet you've never even seen a CATV franchise, or the dozen of pages of specifications agreed to by both the CATV company and the local government. The CATV company isn't a Santa Clause machine, and local governments know why there are limits to the service provided. If there were't, no one could afford to build or operate a CATV system. You've never designed a headend, or a physical plant If they build to supply higher port levels, it has to start at the headend, and requires closer spaced trunk amplifers. The system noise goes up from all of the cascaded amplifers, and the equipment runs hotter, withj a very reduced service life. When you can design an RF distribution system of more than 500 MHz bandwidth and has over 10,000 output ports, with the gain stabilized to a couple dBmv 20 miles from the headend and over a range from sub zero F to + 100 F then you can tell me I'm wrong. One headend I designed and built was only off by .1 dBmv at the test port on the first trunk amp which was a half mile from the head end. If you can do better than that, I'll listen to you and your opinions -- You can't have a sense of humor, if you have no sense. |
#51
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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On 2/9/2012 9:35 PM, Michael A. Terrell wrote:
Grow up. That is an excessive length drop. A standard drop is under 100 feet. You think you know everything, and that the world has to live by your rules. You don't, and it doesn't. I'll bet you've never even seen a CATV franchise, or the dozen of pages of specifications agreed to by both the CATV company and the local government. The CATV company isn't a Santa Clause machine, and local governments know why there are limits to the service provided. If there were't, no one could afford to build or operate a CATV system. You've never designed a headend, or a physical plant If they build to supply higher port levels, it has to start at the headend, and requires closer spaced trunk amplifers. The system noise goes up from all of the cascaded amplifers, and the equipment runs hotter, withj a very reduced service life. When you can design an RF distribution system of more than 500 MHz bandwidth and has over 10,000 output ports, with the gain stabilized to a couple dBmv 20 miles from the headend and over a range from sub zero F to + 100 F then you can tell me I'm wrong. One headend I designed and built was only off by .1 dBmv at the test port on the first trunk amp which was a half mile from the head end. If you can do better than that, I'll listen to you and your opinions Cool! You seem to know what you are up to. Can you put rough numbers around what you mentioned? Like what are providers legally required to deliver at the far end of the drop? Thanks. tom K0TAR |
#52
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() tom wrote: On 2/9/2012 9:35 PM, Michael A. Terrell wrote: Grow up. That is an excessive length drop. A standard drop is under 100 feet. You think you know everything, and that the world has to live by your rules. You don't, and it doesn't. I'll bet you've never even seen a CATV franchise, or the dozen of pages of specifications agreed to by both the CATV company and the local government. The CATV company isn't a Santa Clause machine, and local governments know why there are limits to the service provided. If there were't, no one could afford to build or operate a CATV system. You've never designed a headend, or a physical plant If they build to supply higher port levels, it has to start at the headend, and requires closer spaced trunk amplifers. The system noise goes up from all of the cascaded amplifers, and the equipment runs hotter, withj a very reduced service life. When you can design an RF distribution system of more than 500 MHz bandwidth and has over 10,000 output ports, with the gain stabilized to a couple dBmv 20 miles from the headend and over a range from sub zero F to + 100 F then you can tell me I'm wrong. One headend I designed and built was only off by .1 dBmv at the test port on the first trunk amp which was a half mile from the head end. If you can do better than that, I'll listen to you and your opinions Cool! You seem to know what you are up to. Can you put rough numbers around what you mentioned? Like what are providers legally required to deliver at the far end of the drop? We were required to deliver 0 dBmv at the end of 100 feet of RG-59 or RG-6 for two sets per the franchise. The system was designed at +10 dBmv at the tap to allow for three or four TVs at the 100 foot range. That was on a 36 channel system with RCA modulators & HST. It was done for two reasons. To have a little extra signal available when the system was built, and for conversion for a 300 MHz plant to a 450 MHz plant without respacing the trunk amplifiers. I build a headend & interface to tie two incompatible community loops together. Ours was a sub split loop, and the other CATV company used mid split. We used 2 & 12 for pilots, so we fed them Channel 2 into their return, and down converted their feed to T-9 for our return. That headend had two RCA HSP and a combiner. The interface was another HSP in a large stainless steel NEMA box mounted to a power pole at the boundary of the two systems. A pair of two way splitters were used to route the signals between the systems, as well as into and out of the HSP. The other company wanted us to install a modulator and a demodulator at the boundary to give us audio & video, and another pair from our side so the interface would be baseband. Their design was over $15,000 in hardware alone. My design was under $3000 for all the hardware & labor to install. I had system designers from both sides telling me it wouldn't work, but it did the job with no problems. ![]() -- You can't have a sense of humor, if you have no sense. |
#53
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On 2/9/2012 10:34 PM, Michael A. Terrell wrote:
tom wrote: On 2/9/2012 9:35 PM, Michael A. Terrell wrote: Cool! You seem to know what you are up to. Can you put rough numbers around what you mentioned? Like what are providers legally required to deliver at the far end of the drop? We were required to deliver 0 dBmv at the end of 100 feet of RG-59 or RG-6 for two sets per the franchise. The system was designed at +10 dBmv at the tap to allow for three or four TVs at the 100 foot range. That was on a 36 channel system with RCA modulators& HST. It was done for two reasons. To have a little extra signal available when the system was built, and for conversion for a 300 MHz plant to a 450 MHz plant without respacing the trunk amplifiers. I build a headend& interface to tie two incompatible community loops together. Ours was a sub split loop, and the other CATV company used mid split. We used 2& 12 for pilots, so we fed them Channel 2 into their return, and down converted their feed to T-9 for our return. That headend had two RCA HSP and a combiner. The interface was another HSP in a large stainless steel NEMA box mounted to a power pole at the boundary of the two systems. A pair of two way splitters were used to route the signals between the systems, as well as into and out of the HSP. The other company wanted us to install a modulator and a demodulator at the boundary to give us audio& video, and another pair from our side so the interface would be baseband. Their design was over $15,000 in hardware alone. My design was under $3000 for all the hardware& labor to install. I had system designers from both sides telling me it wouldn't work, but it did the job with no problems. ![]() Very nice. We were much more constrained on the install I mentioned up the thread a ways. The fiber was fed at E1 speed, which probably didn't work it very hard. We had an issue at one point. This was a distributed proc/data system, one of the first. Each cabinet was a standalone PBX. And you could make 126 of them look like one. And each could survive on its own. First fiber campus we'd done. Staggered cut to the new infrastructure. Fun stuff. At one point we had to do the cutover to the other large pice of the system. Each end connected the fiber. 0 signal. TDR from A end showed 700 meters from A end, 800 meters from end B. Length from A to B is 1500 meters. The work that occurred because of that was not fun. Had to go get the guy doing fusion splicing. Joy. Midnight trip to Pittsburgh with the salesman. Actually it was fun. Not much traffic at night. Landing pattern at 160mph in between DC9s into Pittsburgh at about midnight. And they didn't like 160 at all. This was scary. Quickest turnoff onto a taxiway I've ever experienced. Of course the taxiway may not have been one. We didn't care. tom K0TAR |
#54
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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On Feb 9, 6:35*pm, "Sal" wrote:
"JIMMIE" wrote in message ... On Feb 8, 2:00 pm, amdx wrote: Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. I don't has access to electricity at the utility post, so an amp is out. Although I could try an amp at the cable box end. Is that reasonable? I would run two cables if there was a way to make it increase signal strength. Getting anymore from the cable company is not an option. Any ideas to get a better signal? Mikek PS. When the signal fails it seems channel 41 is ok and above 42 it breaks up. Curious to know if there is an unusual frequency jump between those two digital channels. Google your cable box model. You should able to find ifo on how to pull up a menu that shows signal strengh. -60dbm is about where my sigal starts droping out Jimmie ================================================== === Yes, but be mindful of the difference between dBm and dBmV. * *The cable industry often deals in levels *on the dBmV scale. There are places like this ... http://www.maxim-ic.com/app-notes/index.mvp/id/808 where you can see some conversion equations. *Jimmie's -60dBm equals -11.25 dBmV. Same power level -- different scale. I have long known level requirements for the TV tuner's cousin, the cable modem. *The common DOCSIS 2 cable modems are usually spec'ed for -15dBmV to +15dBmV and the smart operators try to keep inside +/- 12. *Thus, you can see that Jimmie's -11.25dBmV is near the low limit and that dropouts become more likely in that neighborhood. I little bit of google snooping revealed that DTV cable boxes would like 0dBmV and will usually be okay with -10dBmV to +10dBmV. *Almost the same. i hope this helps. "Sal" "Sal"- Hide quoted text - - Show quoted text - Sal, A relative number by any other name would smell as sweet. The reccomendations for my box is about the same but it works well below that at least according to what I measure withe the cable box. BTW it just says 'db'. dBm was an assumption on my part.. Jimmie Jimmie |
#55
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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On Feb 9, 12:01*pm, Jeff Liebermann wrote:
On Thu, 09 Feb 2012 07:54:19 -0600, amdx wrote: My drivel: At my home, knology recently upgraded there system for faster internet.. A cableman said he heard me radiating a block away. he came in and changed 7 crimp type connectors in my attic a couple of cable runs. Speedtest.com went from 6 Mbps to over 11 Mbps with just those changes.. Yep, that's the way it works. *Compression type F connectors work well. *Crimp type are junk. *The catch is that there are probably 100 different types of connectors, each with their own compression tools, intended to fit about 8 different types of 75 ohm coax (RG6a/u, RG59/u, single shielded, double shielded, quad shielded, direct burial, etc). *Mixing connector types and cables doesn't work. *I got fed up and "obtained" a 1000ft roll of double shielded RG6a/u, a big of matching F, BNC, and phono connectors, a compression tool, a stripping tool, and replaced all the junk cables in the house. If it's Comcast, you will probably still have the lower 72 channels doing analog. Remove the set top box and plug in your TV directly. Oh, if that is the fact, I may get me some browny points, If I can get the signal up to snuff, then put the vcr back in the line, my wife could record her soaps again. That would get me 15 seconds of hero status! Mikek I'm sure it's true for Comcast in Santa Cruz, CA. *No clue on other areas. *The grand plan is to move all the analog channels to digital area by area: http://www2.insidenova.com/news/2011/jun/22/comcast-removes-scores-ch... http://www2.newsadvance.com/business/2011/nov/09/comcast-switching-an... Unfortunately, your area may be one of those that have moved to all digital. *Hard to tell from here. Just an addition to the termination debate, the marina has about 150 taps, I'd be surprised if 30 of them are connected to a tv and the rest are unterminated. The line generally goes to the utility pedestal into a 2 way splitter and then about 1 ft of cable connects it to the 2 taps for the boat owners. * * * * * * *Mikek Can you determine if the marina is using a distribution amplifier driving a big splitter, or is using a single cable trunk snaked through the marina, with taps (directional couplers) at various points? *If taps, it's easy to install too many taps, or miscalculate the tap type, resulting in level variations along the trunk. http://www.doityourself.com/forum/entertainment-center-tvs-stereos-vc... -- Jeff Liebermann * * 150 Felker St #D * *http://www.LearnByDestroying.com Santa Cruz CA 95060http://802.11junk.com Skype: JeffLiebermann * * AE6KS * *831-336-2558 Jeff, I installed TVRO systems for several years and used a lot of F connectors. Suprisingly the ones I found that worked best were the ultra cheap ones that only took a pair of pliers to fasten These were the ones with the separate crimp rings. Used with some good quality heat shrink tubing this eliminated most of the problems you mention. I dont know why these connectors went away, my only guess is that someone wasn't making enough money on them. Jimmie Jimmie |
#56
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On Fri, 10 Feb 2012 06:17:03 -0800 (PST), JIMMIE
wrote: Jeff, I installed TVRO systems for several years and used a lot of F connectors. Suprisingly the ones I found that worked best were the ultra cheap ones that only took a pair of pliers to fasten These were the ones with the separate crimp rings. Used with some good quality heat shrink tubing this eliminated most of the problems you mention. I dont know why these connectors went away, my only guess is that someone wasn't making enough money on them. Jimmie Yech... Please try this test. Insert such a crimp type F connector and cable into some useless piece of equipment with a type F jack. Pull on the cable hard. In my experience, it doesn't take much to make the cable and connector part ways. Repeat with a screw on connector. Now, repeat the experiment using a properly assembled compression type F connector and cable. It takes considerably more brute force to break the connection. I think the official minimum pull test is 55 lbs, but I'm too lazy to Google for it now. Hiding the workmanship under shrink tube is not very functional. It will have little effect on the pull test. Most of the cable leakage problems I've seen (and found) were due to crimp type F connectors coming apart or badly crimped. That includes both the hex shaped crimp, and ones held together with a crimped ring. Bad: http://www.fconnector.org/wp-content/uploads/2011/12/F-Connector2.jpg Worse: http://www.showmecables.com/images/catalog/product/F-connector-RG59.jpg.ashx?format=jpg Good: http://images.lowes.com/product/converted/783250/783250926510lg.jpg -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#57
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Michael A. Terrell wrote:
Joerg wrote: Michael A. Terrell wrote: Joerg wrote: amdx wrote: Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. Looks like the cable guys screwed up. In your opinion. If their company cable box doesn't deliver a useful and reliable signal I call that screwed up. One pays for a service and expects to either get it delivered as promised or money back. ... If they are delivering the level called for in their franchise, they didn't screw up. It has always been up to the customer to pay for or provide extra equipment for non standard installs. Mike's install does not sound non-standard. 170ft cable drop towards premises which is fairly normal, plus the cable company's set-top box. Grow up. That is an excessive length drop. A standard drop is under 100 feet. You think you know everything, and that the world has to live by your rules. You don't, and it doesn't. ... http://www.starvision.tv/lineup_res.htm Quote "Maximum Drop Length 300 Feet" Now that's what I call good service. ... I'll bet you've never even seen a CATV franchise, or the dozen of pages of specifications agreed to by both the CATV company and the local government. The CATV company isn't a Santa Clause machine, and local governments know why there are limits to the service provided. If there were't, no one could afford to build or operate a CATV system. You've never designed a headend, or a physical plant If they build to supply higher port levels, it has to start at the headend, and requires closer spaced trunk amplifers. The system noise goes up from all of the cascaded amplifers, and the equipment runs hotter, withj a very reduced service life. When you can design an RF distribution system of more than 500 MHz bandwidth and has over 10,000 output ports, with the gain stabilized to a couple dBmv 20 miles from the headend and over a range from sub zero F to + 100 F then you can tell me I'm wrong. One headend I designed and built was only off by .1 dBmv at the test port on the first trunk amp which was a half mile from the head end. If you can do better than that, I'll listen to you and your opinions See above. Obviously others can. And yes, I have designed RF broadband power amps. Lots of them. Not just lashing up boxes but the actual transistor level circuitry including layout guidance for the nasty stuff. Fact is, if a cable company isn't competent to do a 170ft drop they should decline the job. Otherwise it is a screw-up, plain and simple. In our area they'd lose their shirts to the satellite guys because there are many houses like ours where there is no reasonable way to get from the street to the house with a 100ft limit. We have around 200ft that's still there from the early 90's and the previous owner said cable TV worked just fine for them. We are not subscribed because TV ain't that important to us. -- Regards, Joerg http://www.analogconsultants.com/ |
#58
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On 2/8/2012 5:41 PM, Jeff Liebermann wrote:
On Wed, 08 Feb 2012 13:00:12 -0600, wrote: I'm on a boat, about 170ft from the utility post. Ok, 200ft of coax. Presumably RG6a/u. Recently our cable company switched to the wonderful world of Digital TV. You have been assimilated. Resistance is futile. I got the new digital converter and had no picture. Something is wrong. The nominal signal from the cable drop is suppose to be 0dBm. If there's a splitter involved, they like to crank it up to about 10dBm. Your 200ft of RG6a/u will drop the signal from between 4dB at the low end, to about 6dB at the high end. Your set top box is suppose to operate with a 10dB margin. If you would kindly disclose the maker and model, it might be possible to find the specs. Typically, you'll have at least 10dB margin. Even with 200ft of coax, you should have 4 to 6dB margin. The Box is a CISCO RNG100 Only data I know how to get is; Tuner 537.00 Mhz 2dbmv TDC 75.25 Mhz 5dbmv RDC 20.00 Mhz 30.0dbmv Yes 30.0 On the road, will check in this evening. Mikek |
#59
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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On Fri, 10 Feb 2012 11:47:54 -0600, amdx
wrote: The Box is a CISCO RNG100 Only data I know how to get is; Tuner 537.00 Mhz 2dbmv TDC 75.25 Mhz 5dbmv RDC 20.00 Mhz 30.0dbmv Yes 30.0 It's the same as the Cisco Explorer 1540C with some features removed by Comcast. http://www.cincinnatibell.com/shared_content/pdf/tv/exp1540_uguide.pdf How to get into the diagnostics: Press and hold SELECT on front of unit until the MAIL light starts to flash, then press INFO. Or Press and hold PAUSE on remote until MAIL light starts to flash (around 10-15 seconds), then press PAGE-UP (-). On some remotes, PAGE (+) might need to be used instead. I'll guess(tm) that TDC is downstream power, and RDC is upstream power. (20MHz is in the frequency range used by upstream path). 30dBmV is acceptable as the upper limit is about 55dBmv. Remember, this is dB's above 1mv into 75 ohms, not dB's above 1mw into 50 ohms. dBm = dBmV - 48dB So, your 30dBmv is really -18dBm The downstream values are also in the ballpark. See: http://www.dslreports.com/faq/16085 The numbers are for cable modems, but the levels should be similar for DTV. The typical delivered values should be: -10 dBmV to +10 dBmV "Recommended". -11 dBmV to -14 dBmv / +11 dBmV to +14 dBmV "Acceptable". -15 dBmV & +15 dBmV "Maximum". 5dBmV is fairly is good enough and should result in a usable picture. See if you can excavate the SNR numbers. Maybe there's RF garbage on the systems (oscillating distribution amp, ingress, whatever, etc). -- # Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060 # 831-336-2558 # http://802.11junk.com # http://www.LearnByDestroying.com AE6KS |
#60
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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On 2/10/2012 8:07 PM, Michael A. Terrell wrote:
He was a cable grunt when Time Warner built Cube in Cincinnati, so I'd say that he's at least 50 and still a very angry failure. Sounds correct. He's got problems alright. That RADAR site was at Ft. Rucker, and the problem was in the area reserved for the new IFF hardware in the mid '70s. Weathervision was assigned to the space while I was there, but were were in the process of moving to another building when I was told I had orders for Vietnam. I ended up in Alaska instead. Two weeks later that AFRTS station in Vietnam was overrun and the engineers killed. They shipped parts of the transmitter that survived the gunfire to the station in Alaska. ![]() Sorry to hear that. Had friends that survived intact but were still damaged goods from that war. tom K0TAR |
#61
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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On Fri, 10 Feb 2012 08:38:44 -0800, Jeff Liebermann
wrote: I think the official minimum pull test is 55 lbs, but I'm too lazy to Google for it now. 40 lbs outdoors, 30 lbs indoors. http://www.scte.org/documents/pdf/standards/SCTE_124_2011.pdf 6.2.2 Axial Pull Force: The male “F” pin type connector, when attached to cables manufactured to SCTE approved standards, shall withstand a minimum axial pull force of 40 lbs for outdoor and 30 lbs for indoor applications when tested per ANSI/SCTE 99 2009, Test Method For Axial Pull Connector/Drop Cable. I doubt that the crimp connectors could pass the test. -- # Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060 # 831-336-2558 # http://802.11junk.com # http://www.LearnByDestroying.com AE6KS |
#62
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() "Michael A. Terrell" wrote in message m... snip Still easier than having to use blasting caps to find the ends of a broken conduit under the finished concrete floor in a new RADAR site. An old fish tape & blasting cap pushed as far as it would go and BOOM!!!. Then repeat for the other end. Then they used a jackhammer to break out the concrete between the huge floor divots to install new conduit. The electrical contractor had failed to tie the conduit to the rebar & wire mesh before the pour. ![]() Good story. It brought to mind a promotional video I saw for a company that had a process called explosive bonding (of dissimilar metals). They must have been too cheap to rent lights, so they did the demo outside on an old wooden table. It was two guys in overalls and, I swear, they could have retitled it "Gomer and Bubba Find Some Dynamite" and nobody would have noticed. "Sal" |
#63
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() Sal wrote: "Michael A. Terrell" wrote in message m... snip Still easier than having to use blasting caps to find the ends of a broken conduit under the finished concrete floor in a new RADAR site. An old fish tape & blasting cap pushed as far as it would go and BOOM!!!. Then repeat for the other end. Then they used a jackhammer to break out the concrete between the huge floor divots to install new conduit. The electrical contractor had failed to tie the conduit to the rebar & wire mesh before the pour. ![]() Good story. It brought to mind a promotional video I saw for a company that had a process called explosive bonding (of dissimilar metals). They must have been too cheap to rent lights, so they did the demo outside on an old wooden table. It was two guys in overalls and, I swear, they could have retitled it "Gomer and Bubba Find Some Dynamite" and nobody would have noticed. No one wants to let rednecks with dynamite indoors. ;-) -- You can't have a sense of humor, if you have no sense. |
#64
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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Michael A. Terrell wrote:
Joerg wrote: Michael A. Terrell wrote: Joerg wrote: Michael A. Terrell wrote: Joerg wrote: amdx wrote: Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. Looks like the cable guys screwed up. In your opinion. If their company cable box doesn't deliver a useful and reliable signal I call that screwed up. One pays for a service and expects to either get it delivered as promised or money back. ... If they are delivering the level called for in their franchise, they didn't screw up. It has always been up to the customer to pay for or provide extra equipment for non standard installs. Mike's install does not sound non-standard. 170ft cable drop towards premises which is fairly normal, plus the cable company's set-top box. Grow up. That is an excessive length drop. A standard drop is under 100 feet. You think you know everything, and that the world has to live by your rules. You don't, and it doesn't. ... http://www.starvision.tv/lineup_res.htm Quote "Maximum Drop Length 300 Feet" Now that's what I call good service. ... I'll bet you've never even seen a CATV franchise, or the dozen of pages of specifications agreed to by both the CATV company and the local government. The CATV company isn't a Santa Clause machine, and local governments know why there are limits to the service provided. If there were't, no one could afford to build or operate a CATV system. You've never designed a headend, or a physical plant If they build to supply higher port levels, it has to start at the headend, and requires closer spaced trunk amplifers. The system noise goes up from all of the cascaded amplifers, and the equipment runs hotter, withj a very reduced service life. When you can design an RF distribution system of more than 500 MHz bandwidth and has over 10,000 output ports, with the gain stabilized to a couple dBmv 20 miles from the headend and over a range from sub zero F to + 100 F then you can tell me I'm wrong. One headend I designed and built was only off by .1 dBmv at the test port on the first trunk amp which was a half mile from the head end. If you can do better than that, I'll listen to you and your opinions See above. Obviously others can. And yes, I have designed RF broadband power amps. Lots of them. Not just lashing up boxes but the actual transistor level circuitry including layout guidance for the nasty stuff. Fact is, if a cable company isn't competent to do a 170ft drop they should decline the job. Otherwise it is a screw-up, plain and simple. In our area they'd lose their shirts to the satellite guys because there are many houses like ours where there is no reasonable way to get from the street to the house with a 100ft limit. We have around 200ft that's still there from the early 90's and the previous owner said cable TV worked just fine for them. We are not subscribed because TV ain't that important to us. Yawn. You constantly harp about having to meet specs in medical, but whine like a drunken jackass when other businesses have to meet their specs. yes, they could design the sytems to 300 feet or more, but the cost to every customer on the system would go up. In medical I tend to push the envelope and so do the standards committees. Sometimes based on what we do. I designed all my cardiac stuff defibrillator-proof, always, although it was not the law yet. Then they made it law, because it makes sense. Believe it or not but I like to have to meet specs in medical because they protect people. Including you. ... Would you like to pay an extra 20% to 30% just so a very few locations can get better service? Out here we do not pay extra. Our cable companies out tend do use modern technology, not cheap stuff from the 70's. A cable company that isn't competent enough to do more than a measly 100ft would lose their franchise rather quickly. Oh, that's right. You're too cheap to even have cable TV. Read more carefully. I said TV doesn't matter to us, it is not about cost. -- Regards, Joerg http://www.analogconsultants.com/ |
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On Feb 10, 11:38*am, Jeff Liebermann wrote:
On Fri, 10 Feb 2012 06:17:03 -0800 (PST), JIMMIE wrote: Jeff, I installed TVRO systems for several years and used a lot of F connectors. Suprisingly the ones I found that worked best were the ultra cheap ones that only took a pair of pliers to fasten *These were the ones with the separate crimp rings. Used with some good quality heat shrink tubing this eliminated most of the problems you mention. I dont know why these connectors went away, my only guess is *that someone wasn't making enough money on them. Jimmie Yech... Please try this test. *Insert such a crimp type F connector and cable into some useless piece of equipment with a type F jack. *Pull on the cable hard. *In my experience, it doesn't take much to make the cable and connector part ways. *Repeat with a screw on connector. *Now, repeat the experiment using a properly assembled compression type F connector and cable. *It takes considerably more brute force to break the connection. *I think the official minimum pull test is 55 lbs, but I'm too lazy to Google for it now. Hiding the workmanship under shrink tube is not very functional. *It will have little effect on the pull test. Most of the cable leakage problems I've seen (and found) were due to crimp type F connectors coming apart or badly crimped. *That includes both the hex shaped crimp, and ones held together with a crimped ring. Bad: http://www.fconnector.org/wp-content/uploads/2011/12/F-Connector2.jpg Worse: http://www.showmecables.com/images/catalog/product/F-connector-RG59.j... Good: http://images.lowes.com/product/converted/783250/783250926510lg.jpg -- Jeff Liebermann * * 150 Felker St #D * *http://www.LearnByDestroying.com Santa Cruz CA 95060http://802.11junk.com Skype: JeffLiebermann * * AE6KS * *831-336-255 Sorry Jeff but I never used my connectors to support my cables. You may be right but completely irrelevant to me. To me F connector and good connection shouldn't even be used in the same sentence. They are what that are, cheap connectors at best that uses the center conductor of the cable for a contact. Now that is Yech. Heat shrink has nothing to do with the pull test or hiding poor workmanship but it does help keep corrosion down which is the biggest problem with F connectors. Ive never seen one pull apart except in the shoddiest of installations. One of the best things I have found to insure you maintain a good connection is to apply something like DeOxit to the connectors when you assemble them. Best done while all the parts are new. Jimmie |
#66
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On Feb 10, 11:38*am, Jeff Liebermann wrote:
On Fri, 10 Feb 2012 06:17:03 -0800 (PST), JIMMIE wrote: Jeff, I installed TVRO systems for several years and used a lot of F connectors. Suprisingly the ones I found that worked best were the ultra cheap ones that only took a pair of pliers to fasten *These were the ones with the separate crimp rings. Used with some good quality heat shrink tubing this eliminated most of the problems you mention. I dont know why these connectors went away, my only guess is *that someone wasn't making enough money on them. Jimmie Yech... Please try this test. *Insert such a crimp type F connector and cable into some useless piece of equipment with a type F jack. *Pull on the cable hard. *In my experience, it doesn't take much to make the cable and connector part ways. *Repeat with a screw on connector. *Now, repeat the experiment using a properly assembled compression type F connector and cable. *It takes considerably more brute force to break the connection. *I think the official minimum pull test is 55 lbs, but I'm too lazy to Google for it now. Hiding the workmanship under shrink tube is not very functional. *It will have little effect on the pull test. Most of the cable leakage problems I've seen (and found) were due to crimp type F connectors coming apart or badly crimped. *That includes both the hex shaped crimp, and ones held together with a crimped ring. Bad: http://www.fconnector.org/wp-content/uploads/2011/12/F-Connector2.jpg Worse: http://www.showmecables.com/images/catalog/product/F-connector-RG59.j... Good: http://images.lowes.com/product/converted/783250/783250926510lg.jpg -- Jeff Liebermann * * 150 Felker St #D * *http://www.LearnByDestroying.com Santa Cruz CA 95060http://802.11junk.com Skype: JeffLiebermann * * AE6KS * *831-336-2558 You are correct that the problem is in the hex crimp and part of this is because they started making the crimp made on to the connector. The other part is that you have to have a special tool to crimp them. All the pictures that you showed are require a special crimp tool. If these tools are worn or dont fit the particular plug/ cable combination you will get a bad crimp. The old style that is probably 40 years old now that you could crimp the little ring with a pair of pliers worked the best. Unfortunately you can no longer get them, well I do have a few. Jimmie |
#67
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In message
, JIMMIE writes On Feb 10, 11:38*am, Jeff Liebermann wrote: On Fri, 10 Feb 2012 06:17:03 -0800 (PST), JIMMIE wrote: Jeff, I installed TVRO systems for several years and used a lot of F connectors. Suprisingly the ones I found that worked best were the ultra cheap ones that only took a pair of pliers to fasten *These were the ones with the separate crimp rings. Used with some good quality heat shrink tubing this eliminated most of the problems you mention. I dont know why these connectors went away, my only guess is *that someone wasn't making enough money on them. Jimmie Yech... Please try this test. *Insert such a crimp type F connector and cable into some useless piece of equipment with a type F jack. *Pull on the cable hard. *In my experience, it doesn't take much to make the cable and connector part ways. *Repeat with a screw on connector. *Now, repeat the experiment using a properly assembled compression type F connector and cable. *It takes considerably more brute force to break the connection. *I think the official minimum pull test is 55 lbs, but I'm too lazy to Google for it now. Hiding the workmanship under shrink tube is not very functional. *It will have little effect on the pull test. Most of the cable leakage problems I've seen (and found) were due to crimp type F connectors coming apart or badly crimped. *That includes both the hex shaped crimp, and ones held together with a crimped ring. Bad: http://www.fconnector.org/wp-content/uploads/2011/12/F-Connector2.jpg Worse: http://www.showmecables.com/images/catalog/product/F-connector-RG59.j... Good: http://images.lowes.com/product/converted/783250/783250926510lg.jpg -- Jeff Liebermann * * 150 Felker St #D * *http://www.LearnByDestroying.com Santa Cruz CA 95060http://802.11junk.com Skype: JeffLiebermann * * AE6KS * *831-336-255 Sorry Jeff but I never used my connectors to support my cables. You may be right but completely irrelevant to me. To me F connector and good connection shouldn't even be used in the same sentence. They are what that are, cheap connectors at best that uses the center conductor of the cable for a contact. Now that is Yech. Heat shrink has nothing to do with the pull test or hiding poor workmanship but it does help keep corrosion down which is the biggest problem with F connectors. Ive never seen one pull apart except in the shoddiest of installations. One of the best things I have found to insure you maintain a good connection is to apply something like DeOxit to the connectors when you assemble them. Best done while all the parts are new. There little wrong with good quality F-connectors. They are generally good enough for what they were intended for. Problems are usually down to who installs them, and how. For personal outdoor use, I always give any connectors a squirt of WD40 - both during and after installation. [I guess DeOxit would be similar or better.] After cleaning off most of the WD40, I then seal with self-amalgamating tape. Obviously, heatshrink would be better, but for me, is usually less convenient. Mechanically, even screw-on Fs can be hard to dislodge, provided just the right amount of braid is trapped under the screw thread. However, I suppose that sometimes they might not provide the ultimate in screening. In the UK, in the large CATV networks, crimped connectors are well and truly a thing of the past. Anyone using them (even the good ones) would be liable to be hung, drawn and quartered, and then severely punished. The standard connector is of the 'Snap and Seal' type (and similar). In themselves, these are pretty well watertight, and the screening is excellent. It should be almost impossible to pull one off the cable. However, it is unusual for F-connections to appear naked in the open air. The final RF distribution to the home is invariably from a street cabinet which houses an optical node or an RF distribution / line extender amplifier feeding a bank of taps/splitters. The 'traditional' cascade of in-line taps has not been used for a very long time. Under these relatively benign conditions, the F-connectors probably suffer much less from corrosion than those used on taps hanging on aerial messenger wires, USA-style. Nevertheless, there are various purpose-made short 'chunky' rubber sleeves which can be installed first on the tap ports before the cable connectors are screwed on. These seal the screw threads. Personally, I would have liked to have seen a bit of WD40 used but I never managed to drum up much enthusiasm for this as an approved practice. -- Ian |
#68
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() Joerg wrote: Michael A. Terrell wrote: Joerg wrote: Michael A. Terrell wrote: Joerg wrote: Michael A. Terrell wrote: Joerg wrote: amdx wrote: Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. Looks like the cable guys screwed up. In your opinion. If their company cable box doesn't deliver a useful and reliable signal I call that screwed up. One pays for a service and expects to either get it delivered as promised or money back. ... If they are delivering the level called for in their franchise, they didn't screw up. It has always been up to the customer to pay for or provide extra equipment for non standard installs. Mike's install does not sound non-standard. 170ft cable drop towards premises which is fairly normal, plus the cable company's set-top box. Grow up. That is an excessive length drop. A standard drop is under 100 feet. You think you know everything, and that the world has to live by your rules. You don't, and it doesn't. ... http://www.starvision.tv/lineup_res.htm Quote "Maximum Drop Length 300 Feet" Now that's what I call good service. ... I'll bet you've never even seen a CATV franchise, or the dozen of pages of specifications agreed to by both the CATV company and the local government. The CATV company isn't a Santa Clause machine, and local governments know why there are limits to the service provided. If there were't, no one could afford to build or operate a CATV system. You've never designed a headend, or a physical plant If they build to supply higher port levels, it has to start at the headend, and requires closer spaced trunk amplifers. The system noise goes up from all of the cascaded amplifers, and the equipment runs hotter, withj a very reduced service life. When you can design an RF distribution system of more than 500 MHz bandwidth and has over 10,000 output ports, with the gain stabilized to a couple dBmv 20 miles from the headend and over a range from sub zero F to + 100 F then you can tell me I'm wrong. One headend I designed and built was only off by .1 dBmv at the test port on the first trunk amp which was a half mile from the head end. If you can do better than that, I'll listen to you and your opinions See above. Obviously others can. And yes, I have designed RF broadband power amps. Lots of them. Not just lashing up boxes but the actual transistor level circuitry including layout guidance for the nasty stuff. Fact is, if a cable company isn't competent to do a 170ft drop they should decline the job. Otherwise it is a screw-up, plain and simple. In our area they'd lose their shirts to the satellite guys because there are many houses like ours where there is no reasonable way to get from the street to the house with a 100ft limit. We have around 200ft that's still there from the early 90's and the previous owner said cable TV worked just fine for them. We are not subscribed because TV ain't that important to us. Yawn. You constantly harp about having to meet specs in medical, but whine like a drunken jackass when other businesses have to meet their specs. yes, they could design the sytems to 300 feet or more, but the cost to every customer on the system would go up. In medical I tend to push the envelope and so do the standards committees. Sometimes based on what we do. I designed all my cardiac stuff defibrillator-proof, always, although it was not the law yet. Then they made it law, because it makes sense. You do it because they wouldn't hire you if you couldn't meet specs, just like every other consultant, engineer or tech. They might even jail you for your incompetence for not meeting the specs. Believe it or not but I like to have to meet specs in medical because they protect people. Including you. Believe it or not, most technical people have that same standard. You're nothing special. ... Would you like to pay an extra 20% to 30% just so a very few locations can get better service? Out here we do not pay extra. Our cable companies out tend do use modern technology, not cheap stuff from the 70's. A cable company that isn't competent enough to do more than a measly 100ft would lose their franchise rather quickly. Once again the all knowing Jeorge shows his ignorance. 1: You don't know what you're talking about, about the cost of service. Any extra operating costs become part of the basic service that everyone pays. You won't work for nothing, and the utilities don't give them free electricity. The service companies don't repair the equipment for free. Do you have any idea how many amplifiers, taps and set top boxes are needed for 10,000 active ports? To provide hotter ports require more amplifiers, and raises the system noise floor. You 'designed an amplifier'. Big deal. A lot of engineers 'designed and amplifier' and those companies are long out of business. Current CATV amplifiers use hybrids designed specifically for the application and they use them for many reasons. That just leave the design of the 60V modified sine wave to DC power supplies, equalizers, gain control, equalization and remote switching. Some locations also have remote monitoring so the headend can check system status on a continuous basis. It can also report outages when some of the equipment doesn't respond. They can even detect power failures and monitor the battery status in the standby power supplies to give them time to get a portable generator to the area if it is an extended outage. The local Brighthouse system remained in operation here for over four weeks after a hurricane even though the only way to watch TV or access broadband was with battery power or a generator. 2: '70s CATV tech was 12 channel with no return path. It was crude, discrete point to point designs that looked like a ham put together from junk TVs while drinking cheap beer. They were touchy as hell, their tempco sucked, and they were impossible to service without a fully equipped test bed. the power supplies were simple, poorly regulated linear supplies with 85 C electrolytics that died quickly in the southern sun. The large diecast aluminum housing ran hot to the touch without the sun hitting them. That stuff was pretty well all scrapped out by the mid to late '80s by 36 or more channels with return capability. There was so much construction of upgraded systems that there was a severe shortage of new hardware through most of the mid '80s. That '80s tech was gone in all but the smallest systems by 2000. Today most systems are 450 MHz or higher, and are 'Fiber Enhanced' to provide telephone, broadband, movies on demand and pay per view services by breaking the system into cells that cover a few hundred homes, or less. 3: You know nothing about CATV franchises. 'A measly 100 feet' is more than adequate for a hell of a lot of drops & house wiring. If that is what the franchise calls for, THAT IS THE SPECIFICATION, no matter how much you whine like Sloman. A city or county won't pull a franchise over one or two people complaining about weak signals. They receive a fixed percentage of the system revenue every month, and the percentage was set when the economy was up. If they pull the franchise, another provider will offer a much lower percentage. It also involves legal fees, and causes the rates to go up for the users. Why put up with all that for a fraction of a percent of problems. Like people who built a private road a mile long and want to pay the standard install fee when it will cost about $15,000 to run a feeder for that one house. Or like that marina. It isn't a street. It's private property. If they want better service, let them pay for upgrades with .500 cable to each boat, with a .500 to 'F" connector for each boat. That would only cost a few hundred dollars a boat for materials. More if the cable is jacketed. If it isn't it won't last long in salt air. Double that for the hardware and labor to get a good idea of the costs. Oh, that's right. You're too cheap to even have cable TV. Read more carefully. I said TV doesn't matter to us, it is not about cost. Then why are you being such an ignorant prick about the issue when you have no horse in the race? You sound more like Dimbulb every day. I used to think highly of you, but no longer -- You can't have a sense of humor, if you have no sense. |
#69
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() JIMMIE wrote: On Feb 10, 11:38 am, Jeff Liebermann wrote: On Fri, 10 Feb 2012 06:17:03 -0800 (PST), JIMMIE wrote: Jeff, I installed TVRO systems for several years and used a lot of F connectors. Suprisingly the ones I found that worked best were the ultra cheap ones that only took a pair of pliers to fasten These were the ones with the separate crimp rings. Used with some good quality heat shrink tubing this eliminated most of the problems you mention. I dont know why these connectors went away, my only guess is that someone wasn't making enough money on them. Jimmie Yech... Please try this test. Insert such a crimp type F connector and cable into some useless piece of equipment with a type F jack. Pull on the cable hard. In my experience, it doesn't take much to make the cable and connector part ways. Repeat with a screw on connector. Now, repeat the experiment using a properly assembled compression type F connector and cable. It takes considerably more brute force to break the connection. I think the official minimum pull test is 55 lbs, but I'm too lazy to Google for it now. Hiding the workmanship under shrink tube is not very functional. It will have little effect on the pull test. Most of the cable leakage problems I've seen (and found) were due to crimp type F connectors coming apart or badly crimped. That includes both the hex shaped crimp, and ones held together with a crimped ring. Bad: http://www.fconnector.org/wp-content/uploads/2011/12/F-Connector2.jpg Worse: http://www.showmecables.com/images/catalog/product/F-connector-RG59.j... Good: http://images.lowes.com/product/converted/783250/783250926510lg.jpg -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-255 Sorry Jeff but I never used my connectors to support my cables. You may be right but completely irrelevant to me. To me F connector and good connection shouldn't even be used in the same sentence. They are what that are, cheap connectors at best that uses the center conductor of the cable for a contact. Then you would hate most microwave connectors lit SMA. Now that is Yech. Heat shrink has nothing to do with the pull test or hiding poor workmanship but it does help keep corrosion down which is the biggest problem with F connectors. You didn't need heat shrink on good 'F' connectors. Ive never seen one pull apart except in the shoddiest of installations. One of the best things I have found to insure you maintain a good connection is to apply something like DeOxit to the connectors when you assemble them. Best done while all the parts are new. Not needed, if you use flooded outdoor cable. -- You can't have a sense of humor, if you have no sense. |
#70
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() JIMMIE wrote: On Feb 10, 11:38 am, Jeff Liebermann wrote: On Fri, 10 Feb 2012 06:17:03 -0800 (PST), JIMMIE wrote: Jeff, I installed TVRO systems for several years and used a lot of F connectors. Suprisingly the ones I found that worked best were the ultra cheap ones that only took a pair of pliers to fasten These were the ones with the separate crimp rings. Used with some good quality heat shrink tubing this eliminated most of the problems you mention. I dont know why these connectors went away, my only guess is that someone wasn't making enough money on them. Jimmie Yech... Please try this test. Insert such a crimp type F connector and cable into some useless piece of equipment with a type F jack. Pull on the cable hard. In my experience, it doesn't take much to make the cable and connector part ways. Repeat with a screw on connector. Now, repeat the experiment using a properly assembled compression type F connector and cable. It takes considerably more brute force to break the connection. I think the official minimum pull test is 55 lbs, but I'm too lazy to Google for it now. Hiding the workmanship under shrink tube is not very functional. It will have little effect on the pull test. Most of the cable leakage problems I've seen (and found) were due to crimp type F connectors coming apart or badly crimped. That includes both the hex shaped crimp, and ones held together with a crimped ring. Bad: http://www.fconnector.org/wp-content/uploads/2011/12/F-Connector2.jpg Worse: http://www.showmecables.com/images/catalog/product/F-connector-RG59.j... Good: http://images.lowes.com/product/converted/783250/783250926510lg.jpg -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 You are correct that the problem is in the hex crimp and part of this is because they started making the crimp made on to the connector. The other part is that you have to have a special tool to crimp them. All the pictures that you showed are require a special crimp tool. If these tools are worn or dont fit the particular plug/ cable combination you will get a bad crimp. The old style that is probably 40 years old now that you could crimp the little ring with a pair of pliers worked the best. Unfortunately you can no longer get them, well I do have a few. A 'special tool' that only cost about $20 and would do thousands of crimps before it was worn out. I've bought them new, on sale for $8 US. You admitted to using pliers on the cheap crap, and you certainly can't do that with a hex crimp. -- You can't have a sense of humor, if you have no sense. |
#71
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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On Sat, 11 Feb 2012 08:02:37 -0800 (PST), JIMMIE
wrote: Sorry Jeff but I never used my connectors to support my cables. You may be right but completely irrelevant to me. Umm... you've never tripped over a cable, had the equipment fall off the table with the cables attached, run RG6a/u up a pole to where it has to support its own weight, moved furniture with cables still attached, flexed the connector when used as a test lead, pulled cable through the wall or conduit with connectors attached, etc? These are all very common situations which will stress the connector to cable connection. While it might not be a problem for a fixed (stapled in place) installation, it certainly will be a problem for the average home user. http://802.11junk.com/jeffl/pics/drivel/slides/mess01.html I find it odd that outdoor CATV uses quad shielded cable to prevent RF leakage and ingress, and having the cable swept to perfection, while you recommend using inferior F connectors. To me F connector and good connection shouldn't even be used in the same sentence. They are what that are, cheap connectors at best that uses the center conductor of the cable for a contact. Now that is Yech. I do have some issues with RG6a/u that uses copper plated steel core center wire. Mostly, it's a corrosion problem for outdoor connections where the home owner does their own wiring, and uses F connectors without the necessary rubber o-ring needed for waterproofing. I've swept F connectors on the bench and find them quite good and often superior to the rare 75 ohm TNC and BNC connectors near the top end (2GHz for satellite). Incidentally, most of the antennas (that survived a recent storm) on my roof use RG6a/u coax. The mismatch loss between 50 and 75 ohms is minimal. Some use F connectors, but most use BNC's made for RG6a/u. Heat shrink has nothing to do with the pull test or hiding poor workmanship but it does help keep corrosion down which is the biggest problem with F connectors. Ahem. I worked for a marine radio company during the 1970's. I learned a few things about waterproofing and corrosion. Heat shrink doesn't work. Capillary action along the heat shrink to connector boundary will suck the water into the connector. What I use (when needed) is a layer of 1" PTFE tape (or 1/2" if that's all I can find) over the connector. Once in place, a layer of Scotch 66 or other electrical tape to hold it in place. The PTFE will cold flow into the irregularities on the connector surface, and there will be zero capillary action. If I want UV resistance, I spray the tape with clear Krlyon (acrylic) spray. While we're on the topic, I've experimented with various allegedly waterproof enclosures and packages. The only ones I consider genuinely waterproof are sealed and pressurized with dry air. Anything less will eventually leak. Ive never seen one pull apart except in the shoddiest of installations. I have and all too often. I was at the neighbors trying to troubleshoot their Comcast cable tv and modem mess. They had some friend of theirs do the wiring. All the F connectors were crimp ring type and were falling apart. The coax was mostly RG-59 with maybe 80% coverage. I replaced the most disgusting and will finish the job when I have time. One of the best things I have found to insure you maintain a good connection is to apply something like DeOxit to the connectors when you assemble them. Best done while all the parts are new. DeOxit and Cramolin contain oleic acid, which will slightly corrode copper. It's good for CLEANING connectors by removing the oxides, but should not be left on the connector. If you want to make sure that you can take the connector apart after the threads rot in place due to galvanic action between the aluminum receptacle, and the nickel plated crimp type F connector, some silicon or lithium grease would probably be better. Some notes on the contents: http://www.antiqueradios.com/forums/viewtopic.php?t=82058&start=40&sid=71ca160c8f60768 6916a0f355e9ecc34 Jimmie As for special tools, I love them. My various cable preparation tools for various coax cable have saved me countless hours of fumbling with a pocket knife and diagonal cutters. Using the various compression tools on F connectors almost guarantee a good connection, unless I did something dumb. Same with crimp lugs, various LMR-xxx coax cables, and Anderson Power Pole connectors. The days of using a hammer or vice grips to crimp a connector are over. The cost can be substantial, but is well worth it if you work with connectors regularly. http://802.11junk.com/jeffl/antennas/Misc/slides/crimpers.html About $35/ea. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#72
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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Michael A. Terrell wrote:
Joerg wrote: Michael A. Terrell wrote: Joerg wrote: Michael A. Terrell wrote: Joerg wrote: Michael A. Terrell wrote: Joerg wrote: amdx wrote: Hi All, I'm on a boat, about 170ft from the utility post. Recently our cable company switched to the wonderful world of Digital TV. I got the new digital converter and had no picture. I took the box back and got a second box, still no picture. So now I suspect a weak signal and confirm that it is the cable length. The cable company came out and gave me a better cable than I had installed. At this point I have a picture but it is intermittent. The signal at the utility post has 3 outputs and had a four way splitter, I suggested the cable guy put in two 2 way splitters and give me the stronger (first) tap. That got my signal to work almost all the time. I'd like to get the signal to work 100% of the time. Looks like the cable guys screwed up. In your opinion. If their company cable box doesn't deliver a useful and reliable signal I call that screwed up. One pays for a service and expects to either get it delivered as promised or money back. ... If they are delivering the level called for in their franchise, they didn't screw up. It has always been up to the customer to pay for or provide extra equipment for non standard installs. Mike's install does not sound non-standard. 170ft cable drop towards premises which is fairly normal, plus the cable company's set-top box. Grow up. That is an excessive length drop. A standard drop is under 100 feet. You think you know everything, and that the world has to live by your rules. You don't, and it doesn't. ... http://www.starvision.tv/lineup_res.htm Quote "Maximum Drop Length 300 Feet" Now that's what I call good service. ... I'll bet you've never even seen a CATV franchise, or the dozen of pages of specifications agreed to by both the CATV company and the local government. The CATV company isn't a Santa Clause machine, and local governments know why there are limits to the service provided. If there were't, no one could afford to build or operate a CATV system. You've never designed a headend, or a physical plant If they build to supply higher port levels, it has to start at the headend, and requires closer spaced trunk amplifers. The system noise goes up from all of the cascaded amplifers, and the equipment runs hotter, withj a very reduced service life. When you can design an RF distribution system of more than 500 MHz bandwidth and has over 10,000 output ports, with the gain stabilized to a couple dBmv 20 miles from the headend and over a range from sub zero F to + 100 F then you can tell me I'm wrong. One headend I designed and built was only off by .1 dBmv at the test port on the first trunk amp which was a half mile from the head end. If you can do better than that, I'll listen to you and your opinions See above. Obviously others can. And yes, I have designed RF broadband power amps. Lots of them. Not just lashing up boxes but the actual transistor level circuitry including layout guidance for the nasty stuff. Fact is, if a cable company isn't competent to do a 170ft drop they should decline the job. Otherwise it is a screw-up, plain and simple. In our area they'd lose their shirts to the satellite guys because there are many houses like ours where there is no reasonable way to get from the street to the house with a 100ft limit. We have around 200ft that's still there from the early 90's and the previous owner said cable TV worked just fine for them. We are not subscribed because TV ain't that important to us. Yawn. You constantly harp about having to meet specs in medical, but whine like a drunken jackass when other businesses have to meet their specs. yes, they could design the sytems to 300 feet or more, but the cost to every customer on the system would go up. In medical I tend to push the envelope and so do the standards committees. Sometimes based on what we do. I designed all my cardiac stuff defibrillator-proof, always, although it was not the law yet. Then they made it law, because it makes sense. You do it because they wouldn't hire you if you couldn't meet specs, just like every other consultant, engineer or tech. They might even jail you for your incompetence for not meeting the specs. Correct. And the spec for a competent cable company is typically 300ft, as I have shown in the link. Plus the one below. Believe it or not but I like to have to meet specs in medical because they protect people. Including you. Believe it or not, most technical people have that same standard. You're nothing special. Never said I was. Except that I do exceed standards at times where I believe it is necessary. In the case of med electronics that has likely saved lives. I do not subscribe to the idea that a standard is always good enough. Because sometimes they are not. ... Would you like to pay an extra 20% to 30% just so a very few locations can get better service? Out here we do not pay extra. Our cable companies out tend do use modern technology, not cheap stuff from the 70's. A cable company that isn't competent enough to do more than a measly 100ft would lose their franchise rather quickly. Once again the all knowing Jeorge shows his ignorance. No. I suppose you know what MoCA is. Do you consider them ignorant? Because they say the very same thing that I said. What matters is today's state-of-the-art. Nobody cares about what it was in the 80's. Today this is state-of-the-art: http://www.cablefax.com/ct/sections/...ier_44237.html Quote "The Multimedia Over Coax Alliance (MoCA) provides a standard ..." then Quote "The maximum cable distance supported between the root and the last outlet is 300 feet, with a maximum attenuation of 25 dB". And this is for MoCA, not just cable TV. 1: You don't know what you're talking about, about the cost of service. Any extra operating costs become part of the basic service that everyone pays. You won't work for nothing, and the utilities don't give them free electricity. The service companies don't repair the equipment for free. Do you have any idea how many amplifiers, taps and set top boxes are needed for 10,000 active ports? To provide hotter ports require more amplifiers, and raises the system noise floor. You 'designed an amplifier'. Big deal. A lot of engineers 'designed and amplifier' and those companies are long out of business. ... So how many linear RF amplifiers above 1W have you personally designed and guided through layout? Hint: All my clients are still in business and I am sure will be for a long time to come. ... Current CATV amplifiers use hybrids designed specifically for the application and they use them for many reasons. That just leave the design of the 60V modified sine wave to DC power supplies, equalizers, gain control, equalization and remote switching. Some locations also have remote monitoring so the headend can check system status on a continuous basis. It can also report outages when some of the equipment doesn't respond. They can even detect power failures and monitor the battery status in the standby power supplies to give them time to get a portable generator to the area if it is an extended outage. The local Brighthouse system remained in operation here for over four weeks after a hurricane even though the only way to watch TV or access broadband was with battery power or a generator. If that company can't do more than 100ft they'd fail miserably in our market. It's not just our house, it's also the neighbor to the west, and the one after that, and ... 2: '70s CATV tech was 12 channel with no return path. It was crude, discrete point to point designs that looked like a ham put together from junk TVs while drinking cheap beer. They were touchy as hell, their tempco sucked, and they were impossible to service without a fully equipped test bed. the power supplies were simple, poorly regulated linear supplies with 85 C electrolytics that died quickly in the southern sun. The large diecast aluminum housing ran hot to the touch without the sun hitting them. That stuff was pretty well all scrapped out by the mid to late '80s by 36 or more channels with return capability. There was so much construction of upgraded systems that there was a severe shortage of new hardware through most of the mid '80s. That '80s tech was gone in all but the smallest systems by 2000. Today most systems are 450 MHz or higher, and are 'Fiber Enhanced' to provide telephone, broadband, movies on demand and pay per view services by breaking the system into cells that cover a few hundred homes, or less. 3: You know nothing about CATV franchises. 'A measly 100 feet' is more than adequate for a hell of a lot of drops & house wiring. ... No, it is not. If you don't believe me check out Cameron Park, CA, especially the area of the Estates. Then tell me how you want to do that with 100ft drops. ... If that is what the franchise calls for, THAT IS THE SPECIFICATION, ... And the franchise would get kicked out of the market around here. You can't serve this market with a sub-par spec. The big automotive companies had once exhibited a "Well, this is the spec and that's that" attitude like you do in this thread. Then they learned, the hard way. In part by essentially going on welfare which was embarrassing. ... no matter how much you whine like Sloman. A city or county won't pull a franchise over one or two people complaining about weak signals. ... They will if there's a whole big crowd showing up at the next meeting. Now I won't because I only watch the evening news via antenna. But I know a whole lot of folks who would be miffed to be declined service because they are literally addicted to the sports channels. Many would just get satellite though, they market that quite aggressively these days. ... They receive a fixed percentage of the system revenue every month, and the percentage was set when the economy was up. If they pull the franchise, another provider will offer a much lower percentage. It also involves legal fees, and causes the rates to go up for the users. The county folks have one much more important thing on their mind: How to get re-elected. That's what'll matter most to them. They know that seeing complaints about what many people perceive as a utility service they have "rights to" in the paper is not the way to get re-elected. ... Why put up with all that for a fraction of a percent of problems. Like people who built a private road a mile long and want to pay the standard install fee when it will cost about $15,000 to run a feeder for that one house. Or like that marina. It isn't a street. It's private property. If they want better service, let them pay for upgrades with .500 cable to each boat, with a .500 to 'F" connector for each boat. That would only cost a few hundred dollars a boat for materials. More if the cable is jacketed. If it isn't it won't last long in salt air. Double that for the hardware and labor to get a good idea of the costs. Then answer a question I asked you before but you did not comment on it: Why did Mike's cable provider not decline service? Obviously it worked reliably in the analog days and now with DTV it doesn't. If they can't handle the 170ft drop after the digital switch, why did they not inform Mike, cancel the service on their part and send someone out to pick up the set-top box? [...] -- Regards, Joerg http://www.analogconsultants.com/ |
#73
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() Joerg wrote: Michael A. Terrell wrote: Joerg wrote: You do it because they wouldn't hire you if you couldn't meet specs, just like every other consultant, engineer or tech. They might even jail you for your incompetence for not meeting the specs. Correct. And the spec for a competent cable company is typically 300ft, as I have shown in the link. Plus the one below. Believe it or not but I like to have to meet specs in medical because they protect people. Including you. Believe it or not, most technical people have that same standard. You're nothing special. Never said I was. Except that I do exceed standards at times where I believe it is necessary. In the case of med electronics that has likely saved lives. I do not subscribe to the idea that a standard is always good enough. Because sometimes they are not. ... Would you like to pay an extra 20% to 30% just so a very few locations can get better service? Out here we do not pay extra. Our cable companies out tend do use modern technology, not cheap stuff from the 70's. A cable company that isn't competent enough to do more than a measly 100ft would lose their franchise rather quickly. Once again the all knowing Jeorge shows his ignorance. No. I suppose you know what MoCA is. Do you consider them ignorant? Because they say the very same thing that I said. What matters is today's state-of-the-art. Nobody cares about what it was in the 80's. Today this is state-of-the-art: http://www.cablefax.com/ct/sections/...ier_44237.html Did you miss: "IN THE NEXT DECADE"? Quote "The Multimedia Over Coax Alliance (MoCA) provides a standard ..." then Quote "The maximum cable distance supported between the root and the last outlet is 300 feet, with a maximum attenuation of 25 dB". And this is for MoCA, not just cable TV. 1: You don't know what you're talking about, about the cost of service. Any extra operating costs become part of the basic service that everyone pays. You won't work for nothing, and the utilities don't give them free electricity. The service companies don't repair the equipment for free. Do you have any idea how many amplifiers, taps and set top boxes are needed for 10,000 active ports? To provide hotter ports require more amplifiers, and raises the system noise floor. You 'designed an amplifier'. Big deal. A lot of engineers 'designed and amplifier' and those companies are long out of business. ... So how many linear RF amplifiers above 1W have you personally designed and guided through layout? Hint: All my clients are still in business and I am sure will be for a long time to come. ... Current CATV amplifiers use hybrids designed specifically for the application and they use them for many reasons. That just leave the design of the 60V modified sine wave to DC power supplies, equalizers, gain control, equalization and remote switching. Some locations also have remote monitoring so the headend can check system status on a continuous basis. It can also report outages when some of the equipment doesn't respond. They can even detect power failures and monitor the battery status in the standby power supplies to give them time to get a portable generator to the area if it is an extended outage. The local Brighthouse system remained in operation here for over four weeks after a hurricane even though the only way to watch TV or access broadband was with battery power or a generator. If that company can't do more than 100ft they'd fail miserably in our market. It's not just our house, it's also the neighbor to the west, and the one after that, and ... 2: '70s CATV tech was 12 channel with no return path. It was crude, discrete point to point designs that looked like a ham put together from junk TVs while drinking cheap beer. They were touchy as hell, their tempco sucked, and they were impossible to service without a fully equipped test bed. the power supplies were simple, poorly regulated linear supplies with 85 C electrolytics that died quickly in the southern sun. The large diecast aluminum housing ran hot to the touch without the sun hitting them. That stuff was pretty well all scrapped out by the mid to late '80s by 36 or more channels with return capability. There was so much construction of upgraded systems that there was a severe shortage of new hardware through most of the mid '80s. That '80s tech was gone in all but the smallest systems by 2000. Today most systems are 450 MHz or higher, and are 'Fiber Enhanced' to provide telephone, broadband, movies on demand and pay per view services by breaking the system into cells that cover a few hundred homes, or less. 3: You know nothing about CATV franchises. 'A measly 100 feet' is more than adequate for a hell of a lot of drops & house wiring. ... No, it is not. If you don't believe me check out Cameron Park, CA, especially the area of the Estates. Then tell me how you want to do that with 100ft drops. ... If that is what the franchise calls for, THAT IS THE SPECIFICATION, ... And the franchise would get kicked out of the market around here. You can't serve this market with a sub-par spec. The big automotive companies had once exhibited a "Well, this is the spec and that's that" attitude like you do in this thread. Then they learned, the hard way. In part by essentially going on welfare which was embarrassing. ... no matter how much you whine like Sloman. A city or county won't pull a franchise over one or two people complaining about weak signals. ... They will if there's a whole big crowd showing up at the next meeting. Now I won't because I only watch the evening news via antenna. But I know a whole lot of folks who would be miffed to be declined service because they are literally addicted to the sports channels. Many would just get satellite though, they market that quite aggressively these days. A big crowd is what percentage of their customer base? ... They receive a fixed percentage of the system revenue every month, and the percentage was set when the economy was up. If they pull the franchise, another provider will offer a much lower percentage. It also involves legal fees, and causes the rates to go up for the users. The county folks have one much more important thing on their mind: How to get re-elected. That's what'll matter most to them. They know that seeing complaints about what many people perceive as a utility service they have "rights to" in the paper is not the way to get re-elected. No one has a 'right to' cable TV. I was at one meeting where a citizen was demanding that they revoke our franchise. They told him that one complaint out of 10,000 customers wasn't enough reason to revoke. he was as arrogant as you. Everything had to be his way. He got really ****ed when they told him to buy a satellite dish and go away. His demand was a s ignorant as yours. He was demanding that he bring back CBS ARTS, and wouldn't listen that CBS had dropped the service. One other complaint was from a woman demanding that our franchise be pulled because CSPAN was down for a couple days during the modification of a 5 meter dish to multiple feeds. ... Why put up with all that for a fraction of a percent of problems. Like people who built a private road a mile long and want to pay the standard install fee when it will cost about $15,000 to run a feeder for that one house. Or like that marina. It isn't a street. It's private property. If they want better service, let them pay for upgrades with .500 cable to each boat, with a .500 to 'F" connector for each boat. That would only cost a few hundred dollars a boat for materials. More if the cable is jacketed. If it isn't it won't last long in salt air. Double that for the hardware and labor to get a good idea of the costs. Then answer a question I asked you before but you did not comment on it: Why did Mike's cable provider not decline service? Obviously it worked reliably in the analog days and now with DTV it doesn't. If they can't handle the 170ft drop after the digital switch, why did they not inform Mike, cancel the service on their part and send someone out to pick up the set-top box? Sigh. Just because there is a new agreement for the industry doesn't mean that all existing have to comply. Some companies are FIOS. By your standards, everything else should be replaced overnight. Then the distance won't matter at all. I doubt that the income from that marina will ever pay back the construction costs. the system worked for analog, when it was installed. There are no guarantees in life. Stop trying to walk on water, you'll drown. -- You can't have a sense of humor, if you have no sense. |
#74
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() Joerg wrote: http://www.cablefax.com/ct/sections/...ier_44237.html Quote "The Multimedia Over Coax Alliance (MoCA) provides a standard ..." then Quote "The maximum cable distance supported between the root and the last outlet is 300 feet, with a maximum attenuation of 25 dB". And this is for MoCA, not just cable TV. MoCA is home networking, hence the 300 foot figure. A drop at +10 dBmv already allows a 25 dB loss for the cable modem, since they are designed to work to -15 dBmv. That webpage also mentions verifing that a "drop amplifier does not block Moca". In other words, it's home networking for multimedia devices and has nothing to do with the length of the cable drop. It is to allow customers to stream audio and video within their home, and use services like Netflix & Hulu on their TV sets. -- You can't have a sense of humor, if you have no sense. |
#75
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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Michael A. Terrell wrote:
Joerg wrote: Michael A. Terrell wrote: Joerg wrote: You do it because they wouldn't hire you if you couldn't meet specs, just like every other consultant, engineer or tech. They might even jail you for your incompetence for not meeting the specs. Correct. And the spec for a competent cable company is typically 300ft, as I have shown in the link. Plus the one below. Believe it or not but I like to have to meet specs in medical because they protect people. Including you. Believe it or not, most technical people have that same standard. You're nothing special. Never said I was. Except that I do exceed standards at times where I believe it is necessary. In the case of med electronics that has likely saved lives. I do not subscribe to the idea that a standard is always good enough. Because sometimes they are not. ... Would you like to pay an extra 20% to 30% just so a very few locations can get better service? Out here we do not pay extra. Our cable companies out tend do use modern technology, not cheap stuff from the 70's. A cable company that isn't competent enough to do more than a measly 100ft would lose their franchise rather quickly. Once again the all knowing Jeorge shows his ignorance. No. I suppose you know what MoCA is. Do you consider them ignorant? Because they say the very same thing that I said. What matters is today's state-of-the-art. Nobody cares about what it was in the 80's. Today this is state-of-the-art: http://www.cablefax.com/ct/sections/...ier_44237.html Did you miss: "IN THE NEXT DECADE"? Where do you live? The parts of FL I have seen were are technologically advanced, I guess. This stuff is rolled out here in CA, big time. Things like the DCX3200M box and their DVR are MoCA. In case you've missed it, MoCA has already release 2.0. More than a year ago ... -- Regards, Joerg http://www.analogconsultants.com/ |
#76
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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Michael A. Terrell wrote:
Joerg wrote: http://www.cablefax.com/ct/sections/...ier_44237.html Quote "The Multimedia Over Coax Alliance (MoCA) provides a standard ..." then Quote "The maximum cable distance supported between the root and the last outlet is 300 feet, with a maximum attenuation of 25 dB". And this is for MoCA, not just cable TV. MoCA is home networking, hence the 300 foot figure. A drop at +10 dBmv already allows a 25 dB loss for the cable modem, since they are designed to work to -15 dBmv. That webpage also mentions verifing that a "drop amplifier does not block Moca". In other words, it's home networking for multimedia devices and has nothing to do with the length of the cable drop. It is to allow customers to stream audio and video within their home, and use services like Netflix & Hulu on their TV sets. It is the modern cable TV, like it or not. Companies not playing will likely be packing some day. Personally I doubt it'll do much for home networking, at least not appliance control. Computing, yes, and that's the new game in town. Cable companies offering "all-in-one" packages where you get phone, Internet, TV and all that from the "company store". Pretty pricey, last time I looked it was $99/mo and that only for the first year. Probably goes up afterwards. -- Regards, Joerg http://www.analogconsultants.com/ |
#77
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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On 2/10/2012 8:11 PM, Jeff Liebermann wrote:
On Fri, 10 Feb 2012 11:47:54 -0600, wrote: The Box is a CISCO RNG100 Only data I know how to get is; Tuner 537.00 Mhz 2dbmv TDC 75.25 Mhz 5dbmv RDC 20.00 Mhz 30.0dbmv Yes 30.0 It's the same as the Cisco Explorer 1540C with some features removed by Comcast. http://www.cincinnatibell.com/shared_content/pdf/tv/exp1540_uguide.pdf How to get into the diagnostics: Press and hold SELECT on front of unit until the MAIL light starts to flash, then press INFO. Or Press and hold PAUSE on remote until MAIL light starts to flash (around 10-15 seconds), then press PAGE-UP (-). On some remotes, PAGE (+) might need to be used instead. See if you can excavate the SNR numbers. Maybe there's RF garbage on the systems (oscillating distribution amp, ingress, whatever, etc). Hi Jeff, I don't seem to be able to follow your directions, I don't think I have enough buttons. To get the info I posted, Push and hold the power button until the power light blinks, then push power again and the info screen comes up. I don't know what the MAIL light is, I don't have a select button nor a INFO button. Hey started pushing buttons on the remote, found I can scroll through 15 pages off stuuf I don't have a clue about. Got some "RF Statistics on page 5" Current FDC Freq. 75.250 Level 5 dbmv S/N 29db Errs/Ave 0/0 Current Qam Freq. 513 Mhz Level -1dbmv S/N 35db Errs/Ave 11/0 or 11/1 or 11/3 but mostly 11/0 That's all I can see. Mikek |
#78
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() Joerg wrote: Michael A. Terrell wrote: ? Joerg wrote: ?? http://www.cablefax.com/ct/sections/...ier_44237.html ?? ?? Quote "The Multimedia Over Coax Alliance (MoCA) provides a standard ..." ?? ?? then ?? ?? Quote "The maximum cable distance supported between the root and the ?? last outlet is 300 feet, with a maximum attenuation of 25 dB". And this ?? is for MoCA, not just cable TV. ? ? ? MoCA is home networking, hence the 300 foot figure. A drop at +10 ? dBmv already allows a 25 dB loss for the cable modem, since they are ? designed to work to -15 dBmv. That webpage also mentions verifing that a ? "drop amplifier does not block Moca". In other words, it's home ? networking for multimedia devices and has nothing to do with the length ? of the cable drop. It is to allow customers to stream audio and video ? within their home, and use services like Netflix ? Hulu on their TV ? sets. ? It is the modern cable TV, like it or not. Sigh. You never back down, even when you are shown that you are wrong. You are wrong and it's eating you alive. Even the title of the article in your link states: "Testing And Deployment: Making MoCA In-Home Networking Easier" and the article starts with: "Market growth and competition for enhanced video services revenue have MSOs and telcos scrambling for technology and operational advantages. In the next decade, consumer electronics with embedded Internet and IP video support will be widely available." No where does it mention a cable drop. It is a method to transmit digital data between a DVR and any TV connected to the system. Nothing more. It's no wonder you can't get a computer to run properly, when you can't even read a simple networking article like this and understand it. Show me anywhere in that article that states a 300 foot cable TV drop is required. The word drop shows up twice and the first is part of another word: 1: "Additionally, the technician can monitor the MoCA channel for bit errors based on corrected or dropped MoCA packets." ^^^^ 2: "A drop amplifier that does not bypass the MoCA spectrum." ^^^^ This means that some installations require a bi-directional amplifier to compensate for long drops just as they always have. 'Drop Amplifier' refers to a single output CATV amplifier as opposed to the multiport CATV distribution amplifiers used in apartment complexes and condos. Companies not playing will likely be packing some day. Maybe in 30 years, when tiny rural systems can't find anything cheaper on the market and upgrade in bits and pieces. YOU know all about being a cheapskate. Personally I doubt it'll do much for home networking, at least least not appliance control. Why should it? Why would your DVR need to talk to your refrigerator? It is strictly a streaming system for home Entertainment. It's been available here, for years. Hell, even my dad's Direct TV sat system w/DVR does it. Appliances don't need a TV tuner and other crap for a simple ethernet interface. Computing, yes, and that's the new game in town. Cable companies offering "all-in-one" packages where you get phone, Internet, TV and all that from the "company store". Phone and internet are delivered via a cable modem that works to -15 dBmv. Pretty pricey, last time I looked it was $99/mo and that only for the first year. Probably goes up afterwards. It goes a hell of a lot higher than that. That $99 doesn't get you basic cable, internet and phone here. Add on more tiers and hgher bandwith internet and it can pass $250 a month. You are so ignorant that it's scary. Read ALL of the page you linked to and look at the images. It is a lousy home network via coax streaming media standard and nothing more. Not that I ever expect you to be man enough to admit you are wrong. Everything is always someone else's fault. No one ever does anything right but you. The fact that you design medical electronics scares the hell out of me. -- You can't have a sense of humor, if you have no sense. |
#79
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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![]() amdx wrote: On 2/10/2012 8:11 PM, Jeff Liebermann wrote: ? On Fri, 10 Feb 2012 11:47:54 -0600, ? ? wrote: ? ?? The Box is a CISCO RNG100 ?? Only data I know how to get is; ?? Tuner 537.00 Mhz 2dbmv ?? TDC 75.25 Mhz 5dbmv ?? RDC 20.00 Mhz 30.0dbmv Yes 30.0 ?? ? ? It's the same as the Cisco Explorer 1540C with some features removed ? by Comcast. ? ?http://www.cincinnatibell.com/shared...40_uguide.pdf? ? ? How to get into the diagnostics: ? Press and hold SELECT on front of unit until the MAIL light ? starts to flash, then press INFO. ? Or ? Press and hold PAUSE on remote until MAIL light starts to ? flash (around 10-15 seconds), then press PAGE-UP (-). ? On some remotes, PAGE (+) might need to be used instead. ? See if you can excavate the SNR numbers. Maybe there's RF garbage on ? the systems (oscillating distribution amp, ingress, whatever, etc). Hi Jeff, I don't seem to be able to follow your directions, I don't think I have enough buttons. To get the info I posted, Push and hold the power button until the power light blinks, then push power again and the info screen comes up. I don't know what the MAIL light is, I don't have a select button nor a INFO button. Hey started pushing buttons on the remote, found I can scroll through 15 pages off stuuf I don't have a clue about. Got some "RF Statistics on page 5" Current FDC Freq. 75.250 Level 5 dbmv S/N 29db Errs/Ave 0/0 Current Qam Freq. 513 Mhz Level -1dbmv S/N 35db Errs/Ave 11/0 or 11/1 or 11/3 but mostly 11/0 It shows that you have a 6 dB slope, and the high end is 1 dBmv below the standard level. It also shows a lot of errors in the recovered data. QAM is the digital TV signal. Unscrambled channels are referred to as Clear QAM -- You can't have a sense of humor, if you have no sense. |
#80
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Posted to sci.electronics.repair,rec.radio.amateur.antenna,sci.electronics.design
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On 2/12/2012 10:27 AM, amdx wrote:
On 2/10/2012 8:11 PM, Jeff Liebermann wrote: On Fri, 10 Feb 2012 11:47:54 -0600, wrote: The Box is a CISCO RNG100 Only data I know how to get is; Tuner 537.00 Mhz 2dbmv TDC 75.25 Mhz 5dbmv RDC 20.00 Mhz 30.0dbmv Yes 30.0 I just noted I didn't have a picture on ch 42. I went to the RF page, my 537 Mhz numbers were Level 6dbmv S/N 0 db Errs/Ave 0/7 changed to later 0/1742 Status Unlocked VS. When it was working Level -1dbmv S/N 35db Errs/Ave 11/0 or 11/1 or 11/3 but mostly 11/0 Status Locked Mikek |
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