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oldschool@tubes.com: Mar 11 01:11PM -0600 On Fri, 10 Mar 2017 21:06:58 -0500, "Michael A. Terrell"   > 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 shitting 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?

oldschool@tubes.com: Mar 11 01:13PM -0600 On Fri, 10 Mar 2017 19:57:24 +0100, Robert Roland <fake@ddress.no> wrote:   >>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/Images/Marketing/Resources/Calculators/resistor-color-chart.jpg?la=en-US&ts=72364a89-2139-476a-8a54-8d78dacd29ff

oldschool@tubes.com: Mar 11 01:34PM -0600 >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/electronics/1ohm-8ohm2-resistors.php   Seems like this is a common misconception....

dansabrservices@yahoo.com: Mar 11 12:53PM -0800 > 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

Ralph Mowery <rmowery28146@earthlink.net>: Mar 11 04:02PM -0500 In article <91j8cclosatmvgsk7vob6qu45j0h679mf3@4ax.com>, oldschool@tubes.com says...   > According to this chart (and others like it), One Ohm is black -black - > black...   > http://www.digikey.com/-/media/Images/Marketing/Resources/Calculators/resistor-color-chart.jpg?la=en-US&ts=72364a89-2139-476a-8a54-8d78dacd29ff   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.

Ralph Mowery <rmowery28146@earthlink.net>: Mar 11 04:15PM -0500 In article <ihi8ccl5742kl5ca5me3d21fou4h5erbv6@4ax.com>, oldschool@tubes.com 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.

Robert Roland <fake@ddress.no>: Mar 11 11:03PM +0100 >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". -- RoRo

oldschool@tubes.com: Mar 11 05:28PM -0600 On Sat, 11 Mar 2017 16:15:51 -0500, Ralph Mowery   >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.

oldschool@tubes.com: Mar 11 05:58PM -0600 On Sat, 11 Mar 2017 16:02:12 -0500, Ralph Mowery   >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/electronics/1ohm-8ohm2-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.

Ralph Mowery <rmowery28146@earthlink.net>: Mar 11 08:23PM -0500 In article <ahs8ccpid276fcd8du6iebco6ov07ch5d4@4ax.com>, fake@ddress.no says... > 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.

Ralph Mowery <rmowery28146@earthlink.net>: Mar 11 08:34PM -0500 In article <a919cc1me83i0bm0lbdv5ebbrfrubikp9e@4ax.com>, oldschool@tubes.com says... > 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.

Ralph Mowery <rmowery28146@earthlink.net>: Mar 11 08:37PM -0500 In article <b529cc5scqie1d5qsj10tqk7rfh42ik7jd@4ax.com>, oldschool@tubes.com 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.

dansabrservices@yahoo.com: Mar 11 06:33PM -0800 On Saturday, March 11, 2017 at 8:34:48 PM UTC-5, Ralph Mowery wrote: > 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

Michael Black <et472@ncf.ca>: Mar 11 10:26PM -0500

MJC <gravity@mjcoon.plus.com>: Mar 12 09:18AM In article <MPG.332e6d0ab85d4d1f989893@news.east.earthlink.net>, rmowery28146@earthlink.net says... > 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.

MJC <gravity@mjcoon.plus.com>: Mar 12 09:21AM In article <alpine.LNX.2.02.1703112224290.3711@darkstar.example.org>, et472@ncf.ca says...   > 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.   After I had spent a while scrabbling through my Dad's random collection of resistors looking for an acceptable value, I got a strong urge to pick out any one and re-paint the colours...   Mike.

oldschool@tubes.com: Mar 12 05:24AM -0600 On Sat, 11 Mar 2017 20:34:47 -0500, Ralph Mowery >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.

David Lesher <wb8foz@panix.com>: Mar 12 02:57AM >They are designed to handle the regular load + a certain level >of brief heavy overloads, and then on a time/load lesser loads >for a greater period.     The pole pigs around here have 2 fuses. Mine has a 10A and a 15A in series. I asked why two. Turns out the 10A is the rated one and cheap; the 15A is fast, $$$, and solely protects against lightning hits on the primary.   But I know the "rated" load of such a transformer is continuous, and they are routinely overloaded for a few hours. -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close.......................... Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433

David Lesher <wb8foz@panix.com>: Mar 12 02:41AM >something online and it's lost in the post, it's the postal >company's fault, but you still claim from the seller, and the >seller from the postal company.   Have you ever won an argument with Verizontal? -- A host is a host from coast to coast.................wb8foz@nrk.com & no one will talk to a host that's close.......................... Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433

John Robertson <spam@flippers.com>: Mar 11 06:53PM -0800 On 2017/02/03 2:41 PM, Jon Elson wrote: > shutoffs for various machines, and they never do this, I guess because the > contacts are exercised routinely.   > Jon   It is not the breaker per se that was overheating here, it was the breakers contacts to the power bus! I suggest you take that breaker out (safely!!) and check for signs of overheated junction pins on both the breaker wipers and the bus tab.   Had this happen to a friend and it could have been nasty if they hadn't noticed it.   John   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

"Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com>: Mar 11 04:22PM -0500 John Larkin wrote:   > One of the great mysteries of electronics is "where is the current > going?" Sometimes a thermal imager helps figure that out. A little > magnetometer would be fun, not hard to do these days.   I once asked if a discarded head from an old, old hard disk could do that.   There used to be a four-pin probe for PCB current measurement, in the late 80s, but I can't find it. They're probably on ebay but I don't know what name to search for.         --- This email has been checked for viruses by AVG. http://www.avg.com

"Tom Del Rosso" <fizzbintuesday@that-google-mail-domain.com>: Mar 11 04:31PM -0500 John Larkin wrote: >> on a PC board. without cutting traces or requiring a loop of wire. >> <http://www.power-mag.com/pdf/feature_pdf/1327592496_TTI_Layout_1.pdf>   > Looks expensive, and I'd guess not very accurate.   There's one on ebay now for $750.         --- This email has been checked for viruses by AVG. http://www.avg.com

"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Mar 11 07:55PM "Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message news:wsidnT9pS7gJyl7FnZ2dnUU7-d3NnZ2d@earthlink.com...   > That would exceed the length specification for USB cables, which is > five meters. They do sell longer cables with a 'repeater', but there are > still limits.   I'm still wondering why anyone would use an extension cable to plug a USB stick into a computer.   Maybe an old tower case with no front sockets and stashed under the desk......................................

Michael Black <et472@ncf.ca>: Mar 11 03:27PM -0500

ohger1s@gmail.com: Mar 11 11:53AM -0800 > Stupid motherfuckers today, half of them SHOULD be dead.   Geeze Jeff, hanging around Phil lately? LOL.   But anyway, I'm not as old school as you but I don't trust computers in general. Years ago all voting machines were mechanical. They could NOT be hacked unless the laws of physics were broken. They lasted many decades with little maintenance and were 100% accurate. Any computer that can be accessed remotely can be hacked, and I can't but help wonder why politicians fought to sunset mechanical voting machines (and I'm NOT a conspiracy theorist by any stretch).   It comes down to money, but automakers could install a simple mechanical switch that would prevent the car's PCM from having any contact with the outside world unless it was activated. Of course, we could remove the microwave antenna from the car but then we would lose our NAV and Sat radio.

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