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oldschool@tubes.com: Apr 12 12:37AM -0500 When mounting power transistors and chips to a heat sink they often use heat shrink grease to help dissipate the heat. Over the years I have replaced or added this grease which I purchased at Radio Shack. One tube lasted many years for the occasional times I needed it.   I dont need any right now, but I do not have any more on hand for the next time i need it.   Anyhow, I understand this grease is pure 100% silicone grease. I've seen it in both clear and white. I just tuned up my car and replaced the plugs and wires. The auto parts store guy suggested using something called "Spark Plug boot grease". It was only $3 and I know all too well how plug wires tend to get stuck on the plugs and by the time I get them off, I ripped off the terminal inside the boot. So, I bought and used this grease. (which I know also repels moisture from getting into the plug boots).   There is a lot left in the tube and I was just putting it away so I can find it the next time I need it. I was reading the package and it says 100% pure silicone grease.   Hmmmm, wouldn't this be the same stuff used to mount semiconductors to heat sinks? It sure does look the same too... If it's the same, I'll have some for heat sink use too, and in that case, it gets put in with my electronics repair stuff, rather than in my garage. I doubt it's affected by cold weather, but keeping it in the house will keep it at room temp all year long, rather than freezing in the garage in winter.   I thought I'd post this to see if anyone has used this for semiconductors on heat sink, grease, or is there some reason NOT to use this stuff for that purpose?   (If this is the same stuff, it's a heck of a lot cheaper to buy it at an auto parts store).

Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: Apr 12 03:48PM +1000 > this stuff for that purpose?   > (If this is the same stuff, it's a heck of a lot cheaper to buy it at an > auto parts store).   **It's not the same stuff. Heat sink grease, is not really grease. It is a thermally conductive powder, suspended in a suitable medium, that allows it to be spread on a semiconductor. Focus on the words: "Thermally conductive".   I recall that clear stuff from the early 1970s. It is significantly inferior to more modern products.   This will do the trick, at a reasonable price:   https://www.digikey.com.au/product-detail/en/wakefield-vette/126-4/345-1011-ND/340309   Don't muck about, buy the correct stuff to do the job.   -- Trevor Wilson www.rageaudio.com.au

oldschool@tubes.com: Apr 12 01:04AM -0500 On Thu, 12 Apr 2018 15:48:53 +1000, Trevor Wilson   >This will do the trick, at a reasonable price:   >https://www.digikey.com.au/product-detail/en/wakefield-vette/126-4/345-1011-ND/340309   >Don't muck about, buy the correct stuff to do the job.   I guess that answers this question.   Thanks for the speedy reply.   I kind of thought that there could be a special composition involved, but I had to ask to find out.   Thanks again.

jurb6006@gmail.com: Apr 12 12:30AM -0700 I like Dow 340. Also, do you know how to apply it ? You put a daub or a bead near or between the mounting screw(s) and tighten to squeeze out the excess. Spreading it can cause air pockets which defeats the purpose. This method prevents that.   You probably won't find a website that tells this method, but I know of what I speak. Just like you won't find on the web WHY to use 100 % ethylene glycol for your engine coolant, but I can make me case and it is hard to argue against. Anyone wants to dispute it make your case and then my case will bury you. Guaranteed.   You get sort of a feel for how big of a daub or bead to apply. Ideally it should stick slightly out the sides of the device, that assures full coverage. You don't want a huge amount of excess. Also in some cases it is a good idea to push the device on to the heatsink by hand with as much force as possible. Screws strip in aluminum and some of them have a spring type hold down.   The clear stuff is no good. Even the best stuff is actually a thermal insulator but it beats air. the white stuff has microscopic particles in suspension and they do most of the heat conduction. the clear stuff doesn't have it. Don't use it.

"pfjw@aol.com" <peterwieck33@gmail.com>: Apr 12 05:51AM -0700 I like these:   https://www.digikey.com/product-detail/en/bergquist/SP900S-0.009-00-02/BER171-ND/307793     Peter Wieck Melrose Park, PA

tabbypurr@gmail.com: Apr 12 06:06AM -0700 > this stuff for that purpose?   > (If this is the same stuff, it's a heck of a lot cheaper to buy it at an > auto parts store).   heatsink compound is grese loaded with zinc oxide powder. The ZO provides the thermal conductivity.   If you're stuck for some, toothpaste is surprisingly good. I tried it on a high diss AMD 8 core CPU, it only ran a couple of degrees hotter than the proper stuff.     NT

jurb6006@gmail.com: Apr 12 06:34AM -0700 > https://www.digikey.com/product-detail/en/bergquist/SP900S-0.009-00-02/BER171-ND/307793   > Peter Wieck > Melrose Park, PA   Are those the gray rubbery ones ? I like them, no goop required. One place I worked told us to use goop with them anyway, they were kind of anal about things.

"jfeng@my-deja.com" <jfeng@my-deja.com>: Apr 12 06:35AM -0700 > If you're stuck for some, toothpaste is surprisingly good. I tried it on a > high diss AMD 8 core CPU, it only ran a couple of degrees hotter than the > proper stuff. If you need electrical insulation, petroleum jelly is probably better. The main objective is to fill the air gaps.

John-Del <ohger1s@gmail.com>: Apr 12 06:35AM -0700 > I like Dow 340.     I've got several tubes of Dow 340. Very heavy per fluid oz; lots of solids. Expensive stuff but worth it.

oldschool@tubes.com: Apr 12 12:53AM -0500 I have one of those general purpose 12V auto testers. It came with a tubular incandescent bulb, about the size of a 3AG fuse. The bulb burned out, and I am not going to waste a lot of time trying to find a replacement. The whole tester cost about $15.   But before I toss it, I got to thinking that all I really need to do is open it up and wire a LED inside of it. Pretty basic. I think the LED should outlast those bulbs too. I have a bunch of LEDs, but none have the built in resistor.   These are just generic LEDs. I have several colors. None of them have any specifications. All I know is that they are the indicator type, not the super brights. I am aware there are all kinds of math formulas to determine the needed resistor, but since I dont know the LED specs, I can only take a guess at best.   Knowing this, what value resistor should I use? I'd rather go on the high side, so the LED dont burn out. If it seems dim, I can lower the resistor value some. What would be a safe resistance to use? This will ONLY be used on 12V DC automotive batteries.   I'll clip it together before soldering it on place, to make sure it's bright enough and working.   Thanks

gregz <zekor@comcast.net>: Apr 12 08:12AM > I'll clip it together before soldering it on place, to make sure it's > bright enough and working.   > Thanks   10/.015 = ohms. .015 squared times ohm = watts   Greg

tabbypurr@gmail.com: Apr 12 06:02AM -0700 > I'll clip it together before soldering it on place, to make sure it's > bright enough and working.   > Thanks   Run it at 10mA, they're normally specced 20mA max. LEDs drop 2-4v apx. So your R will see 14.4-4=10.4v at 10mA, so 1k is fine.     NT

Richard Jones <news@rgjones.screaming.net>: Apr 12 02:11PM +0100 > I'll clip it together before soldering it on place, to make sure it's > bright enough and working.   > Thanks   LED's have a typical forward Voltage drop of about 1.8V Red, 2V yellow, green, 3.2V blue. So assuming you are using a green one then it's just a quick bit of Ohms law.. Car battery charged is nominally 13.8V, take 2V off for the led = 11.8. Run the led at say 10mA then it's 11.8/0.010 = 1180 Ohms. An easy to find 1k resistor will do nicely.

"jfeng@my-deja.com" <jfeng@my-deja.com>: Apr 12 06:30AM -0700 > tubular incandescent bulb, about the size of a 3AG fuse. The bulb burned > out, and I am not going to waste a lot of time trying to find a > replacement. The whole tester cost about $15. All Electronics in Van Nuys, California (actually part of Los Angeles) has them in 6V and 12V versions for less than US$1 each (the 8V versions are a little more expensive, probably because they were used in Marantz receivers).   https://www.allelectronics.com/category/320300/lamps/fuse-lamps/1.html

Ragnusen Ultred <rragnusen@ultred.com>: Apr 11 12:07PM -0700 Am Wed, 11 Apr 2018 04:57:07 -0700, schrieb Ragnusen Ultred:   > The FTC didn't name which companies it contacted, but notes that the firms > in question sell "automobiles, cellular devices, and video gaming systems > in the United States."   Here's the FTC official notification of the warning to 6 manufacturers. https://www.ftc.gov/news-events/press-releases/2018/04/ftc-staff-warns-companies-it-illegal-condition-warranty-coverage

Fox's Mercantile <jdangus@att.net>: Apr 11 05:36PM -0500 On 4/11/18 2:07 PM, Ragnusen Ultred wrote: [ snip ]   Go peddle your Apple hating shit else where.     -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Ragnusen Ultred <rragnusen@ultred.com>: Apr 11 05:19PM -0700 Am Wed, 11 Apr 2018 17:36:26 -0500, schrieb Fox's Mercantile:   > Go peddle your Apple hating shit else where.   As always, your posts, Snit (aka Fox's Mercantile) are: 1. Never intended to ever be helpful, and, 2. Besides, you don't have the technical expertise to be helpful, and, 3. Hence, you simply guess - where you guessed wrong - yet again.   As always, Snit (aka Fox's Mercantile), you guessed wrong, again in that this FTC warning went to six companies, where the press is debating which six they are, but nobody knows, but where both Microsoft and Apple are called out, as is Sony and Hyundai.

Fox's Mercantile <jdangus@att.net>: Apr 11 08:24PM -0500 On 4/11/18 7:19 PM, Ragnusen Ultred wrote:   >> Go peddle your Apple hating shit else where.   > As always, your posts, Snit (aka Fox's Mercantile) are: > 1. Never intended to ever be helpful, and,   On the contrary, I'll calling you out for being the useless piece of shit you are. > As always, Snit (aka Fox's Mercantile), you guessed wrong,   And as always, you still seem to think I'm Snit.   Moron.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

Ragnusen Ultred <rragnusen@ultred.com>: Apr 11 07:23PM -0700 Am Wed, 11 Apr 2018 20:24:39 -0500, schrieb Fox's Mercantile:   > On the contrary, I'll calling you out for being the useless piece > of shit you are.   Each of your posts proves 1. *You don't actually have any technical expertise*, so, 2. All you can do is post unhelpful unrelated useless drivel.   Just watch.   Back on topic, this should be excellent news for home repair of vehicles and electronic devices, particularly since the big companies that are indicated in the news reports have a huge distribution.   Sony. Apple. Microsoft. Hyundai. etc.   One related question (not for you Snit - you aren't technically competent), is what effect this FTC regulatory decision has on warranties OUTSIDE the USA.   Anyone know what effect this ruling has on, say European customers of the trans-national companies affected?

Fox's Mercantile <jdangus@att.net>: Apr 11 09:55PM -0500 On 4/11/18 9:23 PM, Ragnusen Ultred wrote: > Apple.   Yup. Called it. It's another one of your anti-Apple rants.   Come tomorrow, I'll still be not Snit, and you'll still be a useless troll.   And I've never felt the need to hide behind constantly changing names.   Twelve years ago, I was an expert witness testifying against Motorola in Federal court. Their plan was to claim that any third party repairs were counterfeiting. Fortunately for everyone involved, with the exception of Motorola and their lawyers, that fell through due to my testimony.   <https://www.manatt.com/> Harold Pick, Et. Al. vs Motorola Despite having 375 lawyers, Motorola couldn't make their case. They lost.       -- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com

jurb6006@gmail.com: Apr 12 12:49AM -0700 >"Twelve years ago, I was an expert witness testifying against Motorola in Federal court. "   On what ?   And that link is useless.

Jeff Liebermann <jeffl@cruzio.com>: Apr 11 08:35AM -0700 On Wed, 11 Apr 2018 04:57:07 -0700, Ragnusen Ultred   >FTC Warns Companies eWarranty Void if Removedf Stickers Are Flatly Illegal >https://www.extremetech.com/gaming/267288-ftc-warns-companies-warranty-void-if-removed-stickers-are-flatly-illegal >The 1975 Magnuson-Moss Warranty Act made it illegal for companies to force (...)   I like my warranty better: <http://802.11junk.com/jeffl/pics/drivel/slides/diploma.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

Ragnusen Ultred <rragnusen@ultred.com>: Apr 12 04:56AM -0700 Am Wed, 11 Apr 2018 21:55:43 -0500, schrieb Fox's Mercantile:   > Twelve years ago, I was an expert witness testifying against > Motorola in Federal court.   hehhehheh ... no way... you can *claim* you're a genius, but you're too stupid Snit to not show your true colors in every post.   *Everything you write _proves_ to all you're a moron, Snit.*   You don't have any technical expertise, which is why all you can do is troll, Snit.   You even proved it in this thread.

gregz <zekor@comcast.net>: Apr 11 08:14AM > Grab a couple of couple of large party balloons with the neck cut off. > Stretch over the active face of each cart with a drop of > meths/denatured-alcahol in each balloon and store on a ledge with balloons dangling.   My Canon I hardly use. It just uses ink even while off. Lucky I found cheap cartridges takes 5.   Greg

"Ian Field" <gangprobing.alien1@virginmedia.com>: Apr 03 08:48PM +0100 found it during a rain storm, so no chance of plugging it in till its dried out. And nothing vaguely suitable for a dummy load anyway.   Can't seem to find much online, so might just harvest any useful parts.   Anyone got any info?   Thanks.

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