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Ian Malcolm <See.My.Sig.for.email@totally.invalid>: Dec 01 05:23PM > Does it make sense to use bulk thermal grease? Or is a single use > syringe the best way to go?   > Thank you.   <http://www.dansdata.com/goop.htm>   Just about any reputable brand of thermal transfer grease sold in bulk for general eectronics use will do fine if properly applied.   -- Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED) ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk [at]=@, [dash]=- & [dot]=. *Warning* HTML & >32K emails --> NUL

N_Cook <diverse@tcp.co.uk>: Dec 01 05:35PM On 01/12/2014 16:25, Don Kuenz wrote:   > ( \_/ ) > (='-'=) Don Kuenz > (")_(")   Whichever you use, the absolute minimum you can deliver, not dollops of it by the handfull. Its only to fill any microscopic holes, any excess ,over that ,can only reduce thermal conduction if the excess is not squeezed out, so why place it there initially.

Jeff Liebermann <jeffl@cruzio.com>: Dec 01 09:55AM -0800 On Mon, 1 Dec 2014 16:25:57 +0000 (UTC), Don Kuenz   >This post is about thermal grease for processors. Many PC technicians >think highly of silver thermal grease. What do people here think about >it?   I currently use Arctic Silver because I inherited a box of the stuff from a shop that went out of business. My guess is that I have more than a lifetime supply because I use it VERY sparingly. The idea is to just fill in the cracks and gouges in the heat sink, not plaster the CPU or heatsink with a thick layer. More goop is NOT better. I'll guess that one tube lasts me about 12 Pentium 4 size CPUs. I apply a tiny blob of the stuff to the CPU, and smear it around with a plastic spatula until the entire surface is coated and that there are no lumps or blank areas.   I've also experimented with tooth paste, Vaseline, powdered aluminum suspended in vegetable oil, and other concoctions. Everything works with only subtle differences in CPU operating temperatures.   I also spent some time testing how a polished aluminum heat sink works against a polished CPU. The results were better than with Arctic Silver but had a problem. After a few months of operation, they would overheat. What was happening was the heat sink was expanding and contracting irregularly and would temporarily open a crack between the CPU and heatsink. Dust would get into this crack an create a tiny air gap, which was sufficient to ruin the cooling. With a heat sink that is tightly clamped down, this will not happen, but with the very loose cam clamps used by Dell in some of their early Optiplex motherboards, it became a problem.   >Does it make sense to use bulk thermal grease? Or is a single use >syringe the best way to go?   I have some while silicon grease in a tooth paste size tube. I think it's at least 20 years old and is maybe 1/4th used. It really depends on how many CPU's will need grease. Adjust your quantities accordingly.   Incidentally, if you read the Arctic Silver instructions, they mumble something about the conductivity improving after the machine has been used for a while. That's true because the volatile oils, that make the silver dust flow, need to evaporate. If you leave the stuff open to the air, you'll end up with an unspreadable lump. Therefore, most such compounds need to tubes or syringes of some sort.   Don't forget to clean off the old grease and goo with some solvent before applying the new stuff.     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Michael Black <et472@ncf.ca>: Dec 01 01:38PM -0500

larrymoencurly@my-deja.com: Dec 01 04:54PM -0800 On Monday, December 1, 2014 9:26:20 AM UTC-7, Don Kuenz wrote:   > Many PC technicians think highly of silver thermal grease.   Most PC technicians aren't nearly as skilled or knowledgeable as electronics technicians.   The #1 maker/seller of silver grease, Arctic Silver, doesn't seem to know very much about it, not even the maximum safe voltage, but they did brag of it being used for IGBIs in windmill electronics that ran at high voltage, despite claiming that they didn't do any testing above 12 volts.

isw <isw@witzend.com>: Dec 01 11:08PM -0800 In article <m5i4q1$obk$1@dont-email.me>, Don Kuenz <garbage@crcomp.net> wrote:     > This post is about thermal grease for processors. Many PC technicians > think highly of silver thermal grease. What do people here think about > it?   You can find performance comparisons of various kinds of thermal compounds online. I'd suggest a preference for tests *not* run by anyone who has a horse in the race.   You'll probably find, as I did, that the product-to-product variations are rather subtle.   Isaac

N_Cook <diverse@tcp.co.uk>: Dec 02 08:11AM On 02/12/2014 07:08, isw wrote:   > You'll probably find, as I did, that the product-to-product variations > are rather subtle.   > Isaac   Similarly whenever you see test results for the related product silipads you never see the companies' products cross-compared with mica slips. Mica is non-patentable and dirt cheap with the technical advantage it does not creep , so does loose functionality over time and heat-cycling. What limited in-service testing I've done , mica does a better job in heat transfer, let alone longevity advantage

"William Sommerwerck" <grizzledgeezer@comcast.net>: Dec 02 05:53AM -0800 Mica also has the advantage of being non-conductive.   You would never want to use conductive thermal grease //by itself// when attaching a device directly to a metal heat sink. At least, I don't think so.

"Arfa Daily" <arfa.daily@ntlworld.com>: Dec 02 01:23AM "John-Del" <ohger1s@aol.com> wrote in message news:e4d5ecc5-4700-4852-a88d-126b2989cb1c@googlegroups.com...   > He said it wasn't collapsed, although there's the possibility some liquid > was spilled in the key matrix and is causing an unintended function > command.     Err, no he didn't. He said it wasn't jammed, which is an entirely different thing. I replace many many of these buttons on a variety of equipment that uses them, and it is not at all uncommon for the dome to collapse, whilst the outer control button remains free to move.       > But I've seen a few of these over the years where the scan lines can be > unsoldered at the micro for a test and the fault remains. Sometimes it's > a bad micro caused by a static discharge through the control board.   I've had one or two failed micros over the years, but compared to faulty switches, the relative proportion is vanishingly small   Arfa

John-Del <ohger1s@aol.com>: Dec 02 04:44AM -0800 On Monday, December 1, 2014 8:23:21 PM UTC-5, Arfa Daily wrote:   > thing. I replace many many of these buttons on a variety of equipment that > uses them, and it is not at all uncommon for the dome to collapse, whilst > the outer control button remains free to move.   If you're talking to a customer on the phone and they say it isn't jammed, it's possible the switch collapsed and they can't tell the difference. But Mr. S is clearly no newbie. If he says it's not jammed, it's a fairly safe assumption that the tactile feedback of his play button is the same as the rest of the buttons on the machine.

"William Sommerwerck" <grizzledgeezer@comcast.net>: Dec 02 05:50AM -0800 "Arfa Daily" wrote in message news:bw8fw.77009$c94.39827@fx21.am4...   > I've had one or two failed micros over the years, but compared to faulty > switches, the relative proportion is vanishingly small.   As soon as I find the service manual (which I will be looking for this morning), I will let you guys know. (I'm sure you're waiting with bated breath.)   Practical servicing question, Arfa... If I'm soldering in a CMOS-based device that's battery-operated, would it make sense to leave the batteries in, on the (likely faulty) assumption they would supply a low-impedance path for errant voltages?   Of course not! I shouldn't have written that! I'm making a fool of myself!

Jeff Layman <JMLayman@invalid.invalid>: Dec 01 05:11PM On 30/11/2014 02:35, Phil Allison wrote:   > http://www.hubinet.com/images/BINSON1.JPG   What is the thing on the top on the left (directly behind the "B" of "Binson") that looks like a bottle of Loctite in a battery holder?   --   Jeff

Phil Allison <pallison49@gmail.com>: Dec 01 04:16PM -0800 Jeff Layman wrote:   > > http://www.hubinet.com/images/BINSON1.JPG   > What is the thing on the top on the left (directly behind the "B" of > "Binson") that looks like a bottle of Loctite in a battery holder?   ** That is bottle of light oil.   The steel band needs a smear of oil clean it and so the heads do not make actual contact.   http://www.effectrode.com/magnetic-delay/binson-echorec-manual/   FYI   the steel band is very thin and quite seamless - it appears to be shrink fited onto the alloy drum. Nice bit of machining to make that from a steel tube.   Regular 1/4 inch tape heads are used with a normal HF bias oscillator for record but a permanent magnet for erase. So there is more background noise than tape recorder of the same vintage.   But running at 20ips does help.     ... Phil

Phil Allison <pallison49@gmail.com>: Dec 01 05:17PM -0800 Phil Allison wrote:     > the steel band is very thin and quite seamless - it appears to be shrink fited onto the alloy drum. Nice bit of machining to make that from a steel tube.     ** Forget that.   Info recently posted on the web (not there when I have me example on the bench) suggests the "band" is made from very fine wire, probably a Iron / Nickel alloy, wound onto the drum and then machined smooth.   http://www.effectrode.com/magnetic-delay/binson-echorec-memory-system/   BTW:   The wire cannot be "Constantan" cos like most resistance wire it is non magnetic.   ... Phil

etpm@whidbey.com: Dec 01 12:35PM -0800 I have a computer with a flaky power supply. If the computer is unplugged for a while it will not turn on after it has been plugged in again until sometime has passed. About 10 minutes at room tepmerature. A couple days ago the power lines to my house came down along with the snow. The outside temp was in the low twenties. By the time power had been re-established the office temp was only about 25 degrees. In order to get the computer to start I had to direct the hot air from a blow drier into the back of the computer. After a few minutes it started up. So what device fails when cold? Eric

Jeff Liebermann <jeffl@cruzio.com>: Dec 01 12:49PM -0800 >blow drier into the back of the computer. After a few minutes it >started up. So what device fails when cold? >Eric   Bulging electrolytic capacitors in the power supply. http://www.badcaps.net http://en.wikipedia.org/wiki/Capacitor_plague http://802.11junk.com/jeffl/pics/repair/slides/bad-caps.html   -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: Dec 01 10:24PM +0100 > blow drier into the back of the computer. After a few minutes it > started up. So what device fails when cold? > Eric   A degraded, old capacitor. Those, when cold, have a high serial resistor, and wont work properly. When you heat them, the resistor value will go down quite a lot, and things start working. A very common cause of equipment failure, very dependent on temperature.

etpm@whidbey.com: Dec 01 04:13PM -0800 On Mon, 01 Dec 2014 22:24:12 +0100, Sjouke Burry >and things start working. >A very common cause of equipment failure, very dependent on >temperature. Thanks Jeff and Sjouke. Now I know what to look for. Eric

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