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A lucky find
I went to a rummage sale and the guy had a box of cables for 10 cents
each. Some computer power cords, and some RCA cables, and a couple phone cords. 16 cords total. I offered $1 for the whole box, and he agreed. He asked me why I needed all of them. I told him I work on electronics. Thats when he said he has something I might want. He went in the house and came out with a Kenwood Basic C2, Stereo Control Amplifier. Made in (1984-90). The guy said it's dead, and he was going to throw it away, so I can have it. He said he connected speakers to it and it dont do anything. I got home and was getting out a RCA plug to connect to the output terminals, to hook up a speaker, when I began to look closer at it, and thought "this is a preamp, not a power amp". To make sure what I had, I looked on the web, and found this: https://www.hifiengine.com/manual_li...basic-c2.shtml I have to admit, this is called an "amplifier" so I did sort of think it needed speakers, even though RCA plugs are not usually used for speakers except some of the real old cheap stuff. It turned out this was my lucky day. This preamp sounds great. (And I didn't even connect it to my main power amp yet, I just connected it to a small mono guitar amp that I use for testing stuff in the shop. It needed a little contact cleaner on the selector switches, but works great. I am a little confused though about the phone switch. It has the following selections: MM (Moving Magnet) 47K 100K MC (Moving Coil) 10 ohm 30 ohm 100 ohm Ok, I understand what they are saying, but how do I know if my cartridge is MM or MC, and what the resistance rating is? This appears to be a real useful thing, but I never even knew there were different kinds of cartridges. In the past, I just installed a cartridge and plugged it into "Phono". |
A lucky find
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A lucky find
On Thursday, May 18, 2017 at 9:59:31 AM UTC-4, Ralph Mowery wrote:
It would seem to me you could just use an ohm meter on the cartridge and see what the resistance is. If very low it would be the mc and if say 10K or greater it would be the MM. Ummmmm.......... Be EXCEEDINGLY careful in putting a VOM across any phono cartridge, most especially an MC cartridge. Some (cheap) VOMS will put as much as 9V through the coils - not a good thing. And batteries will deliver current to their chemical limits - thinner-than-human-hair wire does not like heat. Peter Wieck Melrose Park, PA |
A lucky find
On Thursday, May 18, 2017 at 9:15:09 AM UTC-4, wrote:
This appears to be a real useful thing, but I never even knew there were different kinds of cartridges. In the past, I just installed a cartridge and plugged it into "Phono". You have an MM cartridge unless it has an outboard head-amp and/or transformer. Start at 100K. If it sound anemic, move to 47K. Peter Wieck Melrose Park, PA |
A lucky find
On Thu, 18 May 2017, wrote:
I went to a rummage sale and the guy had a box of cables for 10 cents each. Some computer power cords, and some RCA cables, and a couple phone cords. 16 cords total. I offered $1 for the whole box, and he agreed. He asked me why I needed all of them. I told him I work on electronics. Thats when he said he has something I might want. He went in the house and came out with a Kenwood Basic C2, Stereo Control Amplifier. Made in (1984-90). The guy said it's dead, and he was going to throw it away, so I can have it. He said he connected speakers to it and it dont do anything. I got home and was getting out a RCA plug to connect to the output terminals, to hook up a speaker, when I began to look closer at it, and thought "this is a preamp, not a power amp". To make sure what I had, I looked on the web, and found this: https://www.hifiengine.com/manual_li...basic-c2.shtml I have to admit, this is called an "amplifier" so I did sort of think it needed speakers, even though RCA plugs are not usually used for speakers except some of the real old cheap stuff. It turned out this was my lucky day. This preamp sounds great. (And I didn't even connect it to my main power amp yet, I just connected it to a small mono guitar amp that I use for testing stuff in the shop. It needed a little contact cleaner on the selector switches, but works great. I am a little confused though about the phone switch. It has the following selections: MM (Moving Magnet) 47K 100K MC (Moving Coil) 10 ohm 30 ohm 100 ohm Ok, I understand what they are saying, but how do I know if my cartridge is MM or MC, and what the resistance rating is? This appears to be a real useful thing, but I never even knew there were different kinds of cartridges. In the past, I just installed a cartridge and plugged it into "Phono". Most cartridges (unless it's a really cheap turntable in which case it's a crystal or ceramic cartridge) are moving magnet. At least that used to be the case, the moving magnet coil ones were the exception for the ones who wanted to spend more, and you'd need an extra preamp for it. Maybe that's changed, with fewer people owning turntables, maybe the ones using them tend to use moving coil cartridges. But the default is moving magnet. Michael |
A lucky find
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A lucky find
On Thursday, 18 May 2017 14:15:09 UTC+1, wrote:
I went to a rummage sale and the guy had a box of cables for 10 cents each. Some computer power cords, and some RCA cables, and a couple phone cords. 16 cords total. I offered $1 for the whole box, and he agreed. He asked me why I needed all of them. I told him I work on electronics. Thats when he said he has something I might want. He went in the house and came out with a Kenwood Basic C2, Stereo Control Amplifier. Made in (1984-90). The guy said it's dead, and he was going to throw it away, so I can have it. He said he connected speakers to it and it dont do anything. I got home and was getting out a RCA plug to connect to the output terminals, to hook up a speaker, when I began to look closer at it, and thought "this is a preamp, not a power amp". To make sure what I had, I looked on the web, and found this: https://www.hifiengine.com/manual_li...basic-c2.shtml I have to admit, this is called an "amplifier" so I did sort of think it needed speakers, even though RCA plugs are not usually used for speakers except some of the real old cheap stuff. It turned out this was my lucky day. This preamp sounds great. (And I didn't even connect it to my main power amp yet, I just connected it to a small mono guitar amp that I use for testing stuff in the shop. It needed a little contact cleaner on the selector switches, but works great. I am a little confused though about the phone switch. It has the following selections: MM (Moving Magnet) 47K 100K MC (Moving Coil) 10 ohm 30 ohm 100 ohm Ok, I understand what they are saying, but how do I know if my cartridge is MM or MC, and what the resistance rating is? This appears to be a real useful thing, but I never even knew there were different kinds of cartridges. In the past, I just installed a cartridge and plugged it into "Phono". 99.99% of hifi phono carts are MM 47k. You can try the 100k setting without harm, but that may not be true of the MC setting, which expects far lower input. NT |
A lucky find
On Thu, 18 May 2017 10:56:05 -0400, Michael Black wrote:
On Thu, 18 May 2017, wrote: I went to a rummage sale and the guy had a box of cables for 10 cents each. Some computer power cords, and some RCA cables, and a couple phone cords. 16 cords total. I offered $1 for the whole box, and he agreed. He asked me why I needed all of them. I told him I work on electronics. Thats when he said he has something I might want. He went in the house and came out with a Kenwood Basic C2, Stereo Control Amplifier. Made in (1984-90). The guy said it's dead, and he was going to throw it away, so I can have it. He said he connected speakers to it and it dont do anything. I got home and was getting out a RCA plug to connect to the output terminals, to hook up a speaker, when I began to look closer at it, and thought "this is a preamp, not a power amp". To make sure what I had, I looked on the web, and found this: https://www.hifiengine.com/manual_li...basic-c2.shtml I have to admit, this is called an "amplifier" so I did sort of think it needed speakers, even though RCA plugs are not usually used for speakers except some of the real old cheap stuff. It turned out this was my lucky day. This preamp sounds great. (And I didn't even connect it to my main power amp yet, I just connected it to a small mono guitar amp that I use for testing stuff in the shop. It needed a little contact cleaner on the selector switches, but works great. I am a little confused though about the phone switch. It has the following selections: MM (Moving Magnet) 47K 100K MC (Moving Coil) 10 ohm 30 ohm 100 ohm Ok, I understand what they are saying, but how do I know if my cartridge is MM or MC, and what the resistance rating is? This appears to be a real useful thing, but I never even knew there were different kinds of cartridges. In the past, I just installed a cartridge and plugged it into "Phono". Most cartridges (unless it's a really cheap turntable in which case it's a crystal or ceramic cartridge) are moving magnet. At least that used to be the case, the moving magnet coil ones were the exception for the ones who wanted to spend more, and you'd need an extra preamp for it. Maybe that's changed, with fewer people owning turntables, maybe the ones using them tend to use moving coil cartridges. But the default is moving magnet. Michael Good article on that website listed. I have two turntables. The cheap one has a non-removable (as far as I know) cartridge. I dont have a cartridge number, but its an AIWA turntable, and takes an AN-11 stylus. The good turntable has an Audio Technica AT5011E. I also have a spare cartridge from way back, (new in the box), Electro Voice V100. I'm pretty sure the Audio Technica and the Electro Voice are both MM. Probably the AIWA one too, unless thats a crystal or ceramic. I imagine there is a place to look them up, but I have not yet tried to find a website that lists them. As far as using an ohm meter. I do understand the old analog ones are probably not a good idea. I do have a modern digital one (not one of those cheap HF ones). But what about using a VTVM. I may be wrong, but it's my understanding that VTVMs are safe to use on darn near anything. I have two of them, a Heathkit and an Eico. (Presently the Heathkit one tends to act a bit flakey, probably needs new caps, but the Eico works fine). But it's probably easier to just look them up by model. Not to mention..... Both the AT and the EV have FOUR wires coming from them, but when they exit the turntable, they only have TWO (as in RCA plugs). What are the other two wires for????? |
A lucky find
On Thursday, May 18, 2017 at 2:18:08 PM UTC-4, wrote:
As far as using an ohm meter. I do understand the old analog ones are probably not a good idea. I do have a modern digital one (not one of those cheap HF ones). But what about using a VTVM. I may be wrong, but it's my understanding that VTVMs are safe to use on darn near anything. I have two of them, a Heathkit and an Eico. Whoooo Boy! I can think of no reason whatsoever that one should ever use a VTVM in these modern times. Sure, loading a Zenith TransOceanic while performing an alignment via a VTVM makes some of the things go 'by the book', but using a regular high-quality VOM is just fine. Better in many cases. Nor would I ever advocate using a mains-connected VTVM on much audio stuff in any case. Nor do I appreciate them as ancient tools. I do not have enough real-estate on my bench to entertain tools that are not useful. (Presently the Heathkit one tends to act a bit flakey, probably needs new caps, but the Eico works fine). But it's probably easier to just look them up by model. Wheeee..... A typical stereo phono cartridge of any ilk has four (4) wires coming out of it. Some (very) cheap devices have only three, sharing the ground between the channels, but I have not seen one of those for over 30 years. Not to mention..... Both the AT and the EV have FOUR wires coming from them, but when they exit the turntable, they only have TWO (as in RCA plugs). What are the other two wires for????? So, we have: SR/RG (signal right/right ground) SL/LG (signal left/Left ground) Which goes to Right RCA Jack as follows: SR to center post. RG to shell (shield). And the left RCA Jack as follows: SL to the center post. LG to the shell (shield). Magically, four wires go to two wires. There should be a general ground wire in there somewhere - which *SHOULD NOT* go to the pre-amp/amp chassis ground but to either of the shells on either of the jacks. Peter Wieck Melrose Park, PA One cannot make this stuff up! On some great and glorious day the plain folks of the land will reach their heart's desire at last, and the White House will be adorned by a downright moron. H.L. Mencken |
A lucky find
On Thursday, May 18, 2017 at 3:02:12 PM UTC-4, wrote:
On some great and glorious day the plain folks of the land will reach their heart's desire at last, and the White House will be adorned by a downright moron. H.L. Mencken A true prophet.. Two in a row; a *long* 16 years (and one a socialist). Hopefully the next 8 years will be better. |
A lucky find
On 5/18/2017 2:38 PM, wrote:
Hopefully the next 8 years will be better. It's just like watching The Lord of the Flies now. -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com --- This email has been checked for viruses by AVG. http://www.avg.com |
A lucky find
On Thursday, May 18, 2017 at 3:38:44 PM UTC-4, wrote:
A true prophet.. Two in a row; a *long* 16 years (and one a socialist). Hopefully the next 8 years will be better. We have Tweedledumber as the incumbent, and Tweedledum standing in the wings. "Better" is a very relative thing. The incumbent is easily recognized for what he is - much like a hornet's nest hanging in the open. Or a baboon in a zoo flinging feces. The understudy is more akin to a common Krait. Far more subtle - and probably more dangerous if actually allowed power. The US constitution is an interesting document. First, it is based on English Law vs. Napoleonic Law - do you understand the difference? (Everything which is not forbidden is allowed" is a constitutional principle of English law€”an essential freedom of the ordinary citizen or subject.) Next, it contains the 9th & 10th Amendments (AKA - Bill of Rights) which supports the principle expressed above. Then, and least understood: It does not speak to: Marriage Flag Burning Homosexuality Christianity Islam Judaism Buddhism Shintoism Nor any other religion or belief system. Nor any of the other red-meat chimera so near and dear to neocons. Nor, anywhere or in any where does it attempt to legislate morality. That is neither its purpose, nor should it be the results in its application. Sorry for the ramble into politics - but this country has never been so threatened from within as now. Let's call on one of the Founding Fathers - one who "got it right": Freedom of speech is a principal pillar of a free government; when this support is taken away, the constitution of a free society is dissolved, and tyranny is erected on its ruins. Republics and limited monarchies derive their strength and vigor from a popular examination into the action of the magistrates. Those who would give up essential liberty to purchase a little temporary safety deserve neither liberty nor safety. Sell not virtue to purchase wealth, nor Liberty to purchase power. Benjamin Franklin Peter Wieck Melrose Park, PA |
A lucky find
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A lucky find
On Thursday, 18 May 2017 19:18:08 UTC+1, wrote:
On Thu, 18 May 2017 10:56:05 -0400, Michael Black wrote: On Thu, 18 May 2017, wrote: Good article on that website listed. I have two turntables. The cheap one has a non-removable (as far as I know) cartridge. I dont have a cartridge number, but its an AIWA turntable, and takes an AN-11 stylus. The good turntable has an Audio Technica AT5011E. I also have a spare cartridge from way back, (new in the box), Electro Voice V100. I'm pretty sure the Audio Technica and the Electro Voice are both MM. Probably the AIWA one too, unless thats a crystal or ceramic. I imagine there is a place to look them up, but I have not yet tried to find a website that lists them. It's easy to tell magnetic from ceramic. Magnetic styli are in a squarish plastic piece that slides out - or rarely in the case of one of the AT unclips downward. Ceramic styli are unencased, and clip in. Old ones have a flipover sidearm to select from 2 needles, typically LP & 78. The other way to tell them is to wobble the arm slightly when playing. Magnetics let the arm/needle wobble, ceramics don't. As far as using an ohm meter. I do understand the old analog ones are probably not a good idea. I do have a modern digital one (not one of those cheap HF ones). But what about using a VTVM. I may be wrong, but it's my understanding that VTVMs are safe to use on darn near anything. I have two of them, a Heathkit and an Eico. totally pointless. Not to mention..... Both the AT and the EV have FOUR wires coming from them, but when they exit the turntable, they only have TWO (as in RCA plugs). What are the other two wires for????? Each RCA plus has 2 conductors, outer and inner. NT |
A lucky find
In article ,
wrote: Yes, you got a lucky find! I've bought a very nice receiver (a Proton) where the seller said it didn't work at all, and the reason was that he hadn't read the manual and seen that the receiver needs a jumper between "preamp out" and "amp in" if you aren't using an external signal processor. The original jumpers had been lost at some point and the owner didn't do his research... I am a little confused though about the phone switch. It has the following selections: MM (Moving Magnet) 47K 100K MC (Moving Coil) 10 ohm 30 ohm 100 ohm Ok, I understand what they are saying, but how do I know if my cartridge is MM or MC, and what the resistance rating is? Ummm... search the Internet for its part number? Or, measure its DC resistance with an ohmmeter. If it reads a few ohms, it's certainly a moving-coil amplifier. If it reads hundreds, it's probably a moving-magnet (there are some higher-impedance moving coil cartridges but they're less common). The numbers you see above are not those of the cartridges... they're the parallel resistance of the phono stage itself, in that setting. The frequency response of any phono cartridge will depend to some extent on the load resistance. The cartridge maker may specify the recommended load. This appears to be a real useful thing, but I never even knew there were different kinds of cartridges. In the past, I just installed a cartridge and plugged it into "Phono". Cartridges that you can do that with, are almost all moving-magnet (or moving-iron) cartridges. The MM setting, and 47k ohms input impedance, would very probably be the one to choose - that's the industry-standard resistance. MC cartridges typically have a significantly lower output voltage... plugging them into an MM input will result in very low audio levels. One needs a bunch of additional voltage gain (provided by the preamp in MC mode, by an external "head amp", or by a signal transformer) to use a low-output MC cartridge. |
A lucky find
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A lucky find
On 5/18/2017 7:18 PM, rickman wrote:
You are addressing someone who *just* discovered nanofarads. Consider his state of mind. That and RCA connectors actually have TWO connections. -- Jeff-1.0 wa6fwi http://www.foxsmercantile.com --- This email has been checked for viruses by AVG. http://www.avg.com |
A lucky find
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A lucky find
On Thu, 18 May 2017 16:58:43 -0400, Ralph Mowery
wrote: In article , says... As far as using an ohm meter. I do understand the old analog ones are probably not a good idea. I do have a modern digital one (not one of those cheap HF ones). But what about using a VTVM. I may be wrong, but it's my understanding that VTVMs are safe to use on darn near anything. I have two of them, a Heathkit and an Eico. (Presently the Heathkit one tends to act a bit flakey, probably needs new caps, but the Eico works fine). I have a Heathkit VTVM I put together over 40 years ago. I had it out a while back just to see if it still worked. It was slightly flakey and I gave it a shot of the Deoxit on the switches and that made it work like it did when I built it. I don't know what kind of current it puts out in the ohms position. I doubt I will ever use it for anything but maybe where I need a zero center scale meter. That's something I should do with my Heathkit VTVM, use the Deoxit. Maybe that is all it needs.... But I do plan to recap it anyhow. At least the power supply lytics.... I use almost all old tube based test gear, but I normally only work on tube stuff, so I use what matches the equipment. Lately, I have been working on a lot of solid state stuff. I'd rather work on tubes, but this soild state stuff is my own stuff, so I work on it. I generally use all modern test gear on solid state equipment, except for my old Paco tube signal tracer. That thing works on everything and is probably my most used piece of test gear. But I like that old tube test gear, for working on tube stuff. My Sencore scope is solid state, but it's still quite old. I recently got all five of the old Eico probes, plus the high voltage probe they sold. So I am now equipped with probes for almost every need. Eico made the best probes ever, and I really had a tough time getting all of them. I'll probably never need the high voltage one, since I dont work on old CRT tvs, but it came with the other probes. All I need now, is an old 50s era panel truck so I can paint "Radio Repair" on the sides!!! |
A lucky find
On Thu, 18 May 2017 12:02:09 -0700 (PDT), "
wrote: Wheeee..... A typical stereo phono cartridge of any ilk has four (4) wires coming out of it. Some (very) cheap devices have only three, sharing the ground between the channels, but I have not seen one of those for over 30 years. Oops, I was having a brain fart. Yep, these are STEREO cartridges. They need FOUR wires (or at least 3 if they share the ground). |
A lucky find
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A lucky find
Mpfffff...
No, I do not do precision work, which, in point-of-fact is probably the case as the typical Zenith or Hallicrafters or Tesla or SNR radio is not a precision instrument. But, they do just fine aligning with a Fluke meter ILO a VTVM. Nor, of course does Old School. And, given his posts, is likely defeated by anything more complex than a rubber spoon. Peter Wieck Melrose Park, PA |
A lucky find
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