Home |
Search |
Today's Posts |
|
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. |
Reply |
|
|
LinkBack | Thread Tools | Display Modes |
#1
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
There are some sellers on ebay who are selling assorted resistors in
quantity. Some of them claim these assortments contain 0 ohm resistors.... WTF. Wouldn't that be a piece of wire? What would be the point of that? How would you even color code it? |
#2
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#3
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
Also designed for component insertion machines which can't really handle bare wire.
Dan |
#4
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#5
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#6
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
They ca over pass a track without needing 2 vias.
a écrit : There are some sellers on ebay who are selling assorted resistors in quantity. Some of them claim these assortments contain 0 ohm resistors.... WTF. Wouldn't that be a piece of wire? What would be the point of that? How would you even color code it? |
#7
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Friday, March 10, 2017 at 1:20:22 AM UTC-8, wrote:
[about zero-ohm resistors] Now, assuming they use a color code on them, what would it be? I thought it would be Black - Black - Black, but that is actually ONE OHM. (I always have a hard time comprehending that one). So I cant imagine how to color code ZERO Ohms... One black band around the middle is a common marking. http://www.digikey.com/product-detail/en/yageo/ZOR-25-R-52-0R/0.0QTR-ND/18795 |
#8
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
Please note that there are SMD versions of these as well. They will be marked with a single zero(0).
You will often see these used to jump a trace in SMD applications. Dan |
#9
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#10
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#11
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#12
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#13
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Fri, 10 Mar 2017 21:11:57 -0000, MJC
wrote: One ohm is brown, black, gold. Zero ohm should be black, black, any. Are you saying that approximately zero is good enough? I'm not sure I understand your question, but the third band is the multiplier, and since the two first bands are zero, you can multiply with anything you like. So, black, black, white would still be zero. Now that I think about it, one ohm could also be black, brown, black. -- RoRo |
#14
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#15
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Fri, 10 Mar 2017 21:06:58 -0500, "Michael A. Terrell"
wrote: wrote: Please note that there are SMD versions of these as well. They will be marked with a single zero(0). I have seen thee or four zeros, depending on the tolerance. They were 5% and 1%. We used them on circuit boards when a pad wasn't needed. I see that they now sell 0.05% as well: Are you ****ting me..... How can there be a tolerance for ZERO Ohms? Zero IS Zero.... That's just plain silly.... LOL Speaking of silly, next time you see someone wiring a light fixture or lamp, ask them what the tolerance is for the wire they are using.... [Sometimes its fun screwing with people's heads]. http://www.mouser.com/Passive-Components/Resistors/SMD-Resistors-Chip-Resistors/_/N-7h7yu?P=1z0x6qj You will often see these used to jump a trace in SMD applications. Dan Here we go with those initials "SMD" again. I keep seeing that in posts on here and elsewhere. So I better ask... What the heck does SMD mean? |
#16
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Fri, 10 Mar 2017 19:57:24 +0100, Robert Roland
wrote: On Fri, 10 Mar 2017 03:19:06 -0600, wrote: I thought it would be Black - Black - Black, but that is actually ONE OHM. One ohm is brown, black, gold. Zero ohm should be black, black, any. According to this chart (and others like it), One Ohm is black -black - black... http://www.digikey.com/-/media/Image...4-8d78dacd29ff |
#17
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Sat, 11 Mar 2017 12:40:16 -0000, MJC wrote:
In article , says... On Fri, 10 Mar 2017 21:11:57 -0000, MJC wrote: One ohm is brown, black, gold. Zero ohm should be black, black, any. Are you saying that approximately zero is good enough? I'm not sure I understand your question, but the third band is the multiplier, and since the two first bands are zero, you can multiply with anything you like. So, black, black, white would still be zero. Now that I think about it, one ohm could also be black, brown, black. Yes, see the point; I went off half-cock (approx) thinking the "any" was tolerance. I suppose a minus power of ten multiplier would be good, too (I forget the colours)... Mike. And here it's Brown - Black - Gold. http://www.hobby-hour.com/electronic...-resistors.php Seems like this is a common misconception.... |
#18
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Saturday, March 11, 2017 at 2:13:18 PM UTC-5, wrote:
On Fri, 10 Mar 2017 21:06:58 -0500, "Michael A. Terrell" wrote: wrote: Please note that there are SMD versions of these as well. They will be marked with a single zero(0). I have seen thee or four zeros, depending on the tolerance. They were 5% and 1%. We used them on circuit boards when a pad wasn't needed. I see that they now sell 0.05% as well: Are you ****ting me..... How can there be a tolerance for ZERO Ohms? Zero IS Zero.... That's just plain silly.... LOL Speaking of silly, next time you see someone wiring a light fixture or lamp, ask them what the tolerance is for the wire they are using.... [Sometimes its fun screwing with people's heads]. http://www.mouser.com/Passive-Components/Resistors/SMD-Resistors-Chip-Resistors/_/N-7h7yu?P=1z0x6qj You will often see these used to jump a trace in SMD applications. Dan Here we go with those initials "SMD" again. I keep seeing that in posts on here and elsewhere. So I better ask... What the heck does SMD mean? Sorry about not including the definition: Surface Mounted Device Dan |
#20
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#21
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#22
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Sat, 11 Mar 2017 16:15:51 -0500, Ralph Mowery
wrote: In article , says... Here we go with those initials "SMD" again. I keep seeing that in posts on here and elsewhere. So I better ask... What the heck does SMD mean? SMD is surface mounted device. For resistors and capacitors they are usually small and flat. They are usually silver colored on the ends. That is there you solder them to the circuit board. The ICs will often have what seems like very short leads. They lay flat on the circuit board also. Check out this youtube video as to what they are and ways to work with them. For very much work it helps to have a good 10 to 20 power stereo microscope. Now that I know what the initials mean, I know what these are. I have seen them. As far as I'm concerned, they are the devices which cant not be repaired, unless the whole boards are replaced. Yes, i am sure they can be repaired, but it wont be me working on them. Poor eyesite is just part of the reason. Thats why I prefer the old tube stuff to work on, or at least the early transistorized stuff on single layer boards, which contain parts that can be touched without using a tweezers.... For me, IC chips and SMDs took the fun out of electronics as a hobby... (Not that they are bad, but they are not for the home workshop, they are made for robots in factories that create them, and people who have very expensive test gear to trace them). I still recall trying to unsolder some IC chips, and ruining them every time. Then spending days or weeks trying to locate replacement parts, because they are factory numbers that cant just simply be purchased. |
#23
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Sat, 11 Mar 2017 16:02:12 -0500, Ralph Mowery
wrote: I believe you are reading that chart wrong. I have some resistors and checked them out. One is a brown black gold and is 1 ohm. Another is brown black silver and is .1 ohms. That is measured with a Fluke 87 VOM. I don't know for sure, but maybe the resistors do not start off with a black band. Don't have any loose resistors to check, but many on circuit boards are a solid color with a black band in the middle. I bookmarked this site: http://www.hobby-hour.com/electronic...-resistors.php Not only does it calculate the resistor color code, but it even shows a picture. That's a site worth saving.... I never had any problem with the color codes in the old days, because I dont recall ever running into any resistors less than 10 ohms on the old tube gear. It's just these small value ones that are tricky. |
#24
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
In article ,
says... On Sat, 11 Mar 2017 13:13:56 -0600, wrote: According to this chart (and others like it), One Ohm is black -black - black... No, that is not correct. Notice that the fourth band says "multiplier". The chart shows four bands plus tolerance, which means three digits plus a multiplier, plus tolerance. You multiply the first three bands with the multiplier value. Since the three first bands in your example are all zero, you must multiply zero by one ohm, which is still zero. An easy way to remember how the multiplier band works, is to think of it as "number of zeroes". While it does say multiplier, it is not the traditional 'multiply any number by zero and you get zero. It is more like the number of zeros to put at the end. That is why a red red black is 22 ohms and not zero ohms. |
#25
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#26
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#27
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Saturday, March 11, 2017 at 8:34:48 PM UTC-5, Ralph Mowery wrote:
In article , says... Now that I know what the initials mean, I know what these are. I have seen them. As far as I'm concerned, they are the devices which cant not be repaired, unless the whole boards are replaced. Yes, i am sure they can be repaired, but it wont be me working on them. Poor eyesite is just part of the reason. Thats why I prefer the old tube stuff to work on, or at least the early transistorized stuff on single layer boards, which contain parts that can be touched without using a tweezers.... For me, IC chips and SMDs took the fun out of electronics as a hobby... (Not that they are bad, but they are not for the home workshop, they are made for robots in factories that create them, and people who have very expensive test gear to trace them). I still recall trying to unsolder some IC chips, and ruining them every time. Then spending days or weeks trying to locate replacement parts, because they are factory numbers that cant just simply be purchased. I am 67 and just started working with the SMD about 2 years ago. If your hands do not shake too much it is easy if you have the right tools. For the hobby people like me that does not want to spend too much, it takes about 300 to 350 to really get the right equipment. A good microscope can be bought for about $ 190. A hot air and small soldering iron combination is about $ 60. Then a few tweezers, very fine solder,liquid solder, liquid flux and some kapton tape round up most of the other items you need. Get some old computer boards and practice for several days and it will be easy. Be sure to look on youtube for some videos to see how the pros do it. They make it look very easy. One easy way to replace the ICs is to cut the legs from the plastic case and remove them a pin at a time. Don't try to save them. The odd ball factory numbers are something else. There should be some kind of rule they can not use house numbered parts unless it is especially made for that piece of equipment and not used by anyother company. Some companies even sanded off all the numbers on the parts. Probably getting a bit off topic, but when removing SMD parts, I use ChipQuik. Check it out, it works great and the removed part can be used again if it is not the problem. Dan |
#28
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Sat, 11 Mar 2017, Ralph Mowery wrote:
In article , says... I never had any problem with the color codes in the old days, because I dont recall ever running into any resistors less than 10 ohms on the old tube gear. It's just these small value ones that are tricky. For the standard resistors it was almost second nature for me to just look at a resistor and call out the value. There were only a few values used most of the time, and then the last band for the multiplier. Especially when most were the 10 % type. Yes, after a while, you aren't so much "decoding" but just recognize the value connected to the coding. Three red stripes? Of course that's 2200. I can't even tell you what 4.7K is, but I'd know one when I saw it. SO much effort put into mnemonics to remember the color code and cardboard decoder rings, when all you have to do is spend some time looking at resistors, like when you are sorting them out. Michael |
#29
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#30
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#31
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Sat, 11 Mar 2017 20:34:47 -0500, Ralph Mowery
wrote: In article , says... Now that I know what the initials mean, I know what these are. I have seen them. As far as I'm concerned, they are the devices which cant not be repaired, unless the whole boards are replaced. Yes, i am sure they can be repaired, but it wont be me working on them. Poor eyesite is just part of the reason. Thats why I prefer the old tube stuff to work on, or at least the early transistorized stuff on single layer boards, which contain parts that can be touched without using a tweezers.... For me, IC chips and SMDs took the fun out of electronics as a hobby... (Not that they are bad, but they are not for the home workshop, they are made for robots in factories that create them, and people who have very expensive test gear to trace them). I still recall trying to unsolder some IC chips, and ruining them every time. Then spending days or weeks trying to locate replacement parts, because they are factory numbers that cant just simply be purchased. I am 67 and just started working with the SMD about 2 years ago. If your hands do not shake too much it is easy if you have the right tools. For the hobby people like me that does not want to spend too much, it takes about 300 to 350 to really get the right equipment. A good microscope can be bought for about $ 190. A hot air and small soldering iron combination is about $ 60. Then a few tweezers, very fine solder,liquid solder, liquid flux and some kapton tape round up most of the other items you need. Get some old computer boards and practice for several days and it will be easy. Be sure to look on youtube for some videos to see how the pros do it. They make it look very easy. One easy way to replace the ICs is to cut the legs from the plastic case and remove them a pin at a time. Don't try to save them. The odd ball factory numbers are something else. There should be some kind of rule they can not use house numbered parts unless it is especially made for that piece of equipment and not used by anyother company. Some companies even sanded off all the numbers on the parts. The old tube stuff was made to be repaired. You'd unplug a tube and stick it in a tester. If it was not the tubes, you'd begin checking the passive parts. With ICs, you cant unplug them or test them. They DO make sockets for them, but they are never used on consumer products, and if they could be unplugged, there are no testers, at least not a general purpose tester for all ICs. I suppose companies have testers for specific ICs that they use. Cutting the leads on the ICs is a good idea if you know they need to be replaced, but much of the time you want to remove them to test them (as best as possible) out of the circuit. At least single transistors could be unsoldered and tested. When I used them for some projects that I built, I always put them in sockets. Things just are not made to be repaired these days. And like you said, the part numbers are often "house numbers", which makes it impossible to fix the stuff. I guess thats why computers are made wih boards that are just unplugged and replaced. The boards themselves are the components, but often times the boards cost more than the whole device. |
#32
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Sat, 11 Mar 2017 20:37:27 -0500, Ralph Mowery
wrote: In article , says... I never had any problem with the color codes in the old days, because I dont recall ever running into any resistors less than 10 ohms on the old tube gear. It's just these small value ones that are tricky. For the standard resistors it was almost second nature for me to just look at a resistor and call out the value. There were only a few values used most of the time, and then the last band for the multiplier. Especially when most were the 10 % type. It's been nearly 40 years since I did any serious work on electronics. But I still remembered the color codes, many of the common resistor sizes, common cap sizes, and the numbers on the most used tubes. I dont think I ever used a resistor below 10 ohms, except the wirewound types, such as the old huge 8 ohm WW ones that I used to use for speaker loads. I think they were rated at 100 watts. I saved a lot of that stuff, but much of it has vanished over the years. |
#33
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#34
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#35
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
On Sun, 12 Mar 2017, MJC wrote:
In article , says... At least single transistors could be unsoldered and tested. When I used them for some projects that I built, I always put them in sockets. There's also the problem that at the speeds stuff works at these days, the extra spacing is electrically significant. I remember playing with a tunnel diode in the 1960s when they were commercially available and they were quite difficult to stop oscillating! I think that accounts for why in hobby circles, their attraction was mostly as an oscillator. "WIreless mics", QRP transmitters on the amateur six metre band, oscillator/mixer in various receiver circuits. Offhand, I can't remember much of their use as amplifiers in hobby circles. Michael |
#36
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
1% sur 0 ohms !!! Je ne vois pas
Chris Jones a écrit : On 10/03/2017 13:30, wrote: There are some sellers on ebay who are selling assorted resistors in quantity. Some of them claim these assortments contain 0 ohm resistors.... WTF. Wouldn't that be a piece of wire? What would be the point of that? How would you even color code it? The really funny thing is you can buy them in 1% and 5% tolerance. I'm betting that none of them are within tolerance though. |
#37
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
Bien vu !!
La tolérance en % idem, mais 0 si 0 ohms MJC a écrit : In article t, says... While it does say multiplier, it is not the traditional 'multiply any number by zero and you get zero. It is more like the number of zeros to put at the end. That is why a red red black is 22 ohms and not zero ohms. The multiplier is ten to the power of the colour. Any number to the power of zero is one. Hence the result you cite. Mike. |
#38
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
|
#39
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
wrote in message ... Please note that there are SMD versions of these as well. They will be marked with a single zero(0). You will often see these used to jump a trace in SMD applications. They occasionally double as test points on SMD boards. |
#40
Posted to sci.electronics.repair
|
|||
|
|||
0 (ZERO) Ohm Resistors (WTF)........
wrote in message ... On Saturday, March 11, 2017 at 8:34:48 PM UTC-5, Ralph Mowery wrote: In article , says... Now that I know what the initials mean, I know what these are. I have seen them. As far as I'm concerned, they are the devices which cant not be repaired, unless the whole boards are replaced. Yes, i am sure they can be repaired, but it wont be me working on them. Poor eyesite is just part of the reason. Thats why I prefer the old tube stuff to work on, or at least the early transistorized stuff on single layer boards, which contain parts that can be touched without using a tweezers.... For me, IC chips and SMDs took the fun out of electronics as a hobby... (Not that they are bad, but they are not for the home workshop, they are made for robots in factories that create them, and people who have very expensive test gear to trace them). I still recall trying to unsolder some IC chips, and ruining them every time. Then spending days or weeks trying to locate replacement parts, because they are factory numbers that cant just simply be purchased. I am 67 and just started working with the SMD about 2 years ago. If your hands do not shake too much it is easy if you have the right tools. For the hobby people like me that does not want to spend too much, it takes about 300 to 350 to really get the right equipment. A good microscope can be bought for about $ 190. A hot air and small soldering iron combination is about $ 60. Then a few tweezers, very fine solder,liquid solder, liquid flux and some kapton tape round up most of the other items you need. Get some old computer boards and practice for several days and it will be easy. Be sure to look on youtube for some videos to see how the pros do it. They make it look very easy. One easy way to replace the ICs is to cut the legs from the plastic case and remove them a pin at a time. Don't try to save them. The odd ball factory numbers are something else. There should be some kind of rule they can not use house numbered parts unless it is especially made for that piece of equipment and not used by anyother company. Some companies even sanded off all the numbers on the parts. Probably getting a bit off topic, but when removing SMD parts, I use ChipQuik. Check it out, it works great and the removed part can be used again if it is not the problem. I use a modeller's pencil blowtorch to heat the bare side of the board - when any SMD part moves; I tap the edge of the board on the bench and a whole pile of parts just fall off. |
Reply |
|
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Resistors anyone? | UK diy | |||
MTX 6500D Blown Resistors - resistors.jpg (0/1) | Electronic Schematics | |||
MTX 6500D Blown Resistors - resistors.jpg (1/1) | Electronic Schematics | |||
Resistors | UK diy | |||
Fusible Resistors | Electronics Repair |