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Cursitor Doom <curd@notformail.com>: Mar 06 01:26PM On Mon, 29 Feb 2016 21:47:38 +0100, Dimitrij Klingbeil wrote:     > "Never connect the ground (common, chassis etc.) of any test equipment > to the switching node (power transistor collector, drain or power IC > output pin and its associated signals) of a switching power supply!"   As an aside, I'm just a bit mystified as to why anyone would want to do this anyway?   Now, apologies for the delay, but I had the usual accumulation of pressing things to deal with on my return so have only now got around to carrying out the checks last suggested here.   OK, I measured the resonant frequency of the primary circuit (with the chopper NOT disconnected, see notes below) by sweeping a frequency range across the main tranformer's primary input terminals. It's not particularly peaky, so there's a Khz or so on either side of Fo before we get to the -3db shoulders. Fo, with no load connected came out as 17.35kHz.   Under power, with frequency counter connected between T1 and T2 with V1812 removed from circuit shows the PWM chip pulsing at 22.55kHz.   Unfortunately I have no idea what the factory figures should be and whilst it seems like there's a big difference between the PWM chip's output and the primary circuit's resonance, AIUI, they're not supposed to be in sync at any time anyway. But are they supposed to be this far apart?   Notes:   1. I know somewhere it was stated that the chopper transistor should be removed for the resonance test, but I couldn't see the harm in leaving it in. If it invalidates the test, of course, then I'll whip it out and re- do it. If you think it's relevant let me know.   2. I pulled V1812 as someone suggested because the noise coming back down its collector from L1803 might have interfered with the frequency counter's ability to read the clock pulses.

Cursitor Doom <curd@notformail.com>: Mar 06 01:35PM On Sun, 06 Mar 2016 13:26:33 +0000, Cursitor Doom wrote:   > Under power, with frequency counter connected between T1 and T2 with > V1812 removed from circuit shows the PWM chip pulsing at 22.55kHz.   Sorry, ignore that; copied the wrong piece of paper. It should be 20.64kHz. (This is with the load connected.) I then tried again with V1812 re-inserted and got 20.62kHz. Apologies for the earlier error...

DaveC <not@home.cow>: Mar 05 09:14AM -0800 Cleaning up an old rotary mode switch used for 5v logic levels. It has some kind of grease in it.     …which has always confused me: grease is an insulator (well, the grease in this switch is—just tested and it's infinite ohms).   I read that dielectric grease is good to keep contacts sealed against the elements that have high physical pressure (which overcomes any separation provided by the grease) but that signal and other low voltages grease is contra-indicated.   What say y'all?   Thanks.

stratus46@yahoo.com: Mar 05 03:52PM -0800 On Saturday, March 5, 2016 at 9:14:19 AM UTC-8, DaveC wrote: > contra-indicated.   > What say y'all?   > Thanks.   I use GC 10-8101 grease on outdoor F connectors under the weather boot to keep the oxidation down. I opened a 15 year old connection and it looked like new inside. The antenna was trash but the cable was excellent.   http://www.gcelectronics.com/order/DataSheets/10-8101,%2010-8102,%2010-568%20Silicone%20Compound.pdf   G²

DaveC <not@home.cow>: Mar 05 07:55PM -0800 > I use GC 10-8101 grease on outdoor F connectors under the weather boot to > keep the oxidation down. I opened a 15 year old connection and it looked like > new inside. The antenna was trash but the cable was excellent.   You put it inside the boot but not inside the connector (not inside the F-conn), right?   Thanks.

Jeff Liebermann <jeffl@cruzio.com>: Mar 05 08:27PM -0800 >I use GC 10-8101 grease on outdoor F connectors under the weather boot to keep the oxidation down. I opened a 15 year old connection and it looked like new inside. The antenna was trash but the cable was excellent. >http://www.gcelectronics.com/order/DataSheets/10-8101,%2010-8102,%2010-568%20Silicone%20Compound.pdf >G²   GC 10-8101 is a "dielectric grease". From the above URL: "... to prevent electrical power from migrating between circuitry". Dielectric means "insulator" in this case, which is not exactly what I would want in an RF connector. <https://en.wikipedia.org/wiki/Silicone_grease#Dielectric_grease>   Perhaps some conductive grease would make a better connection? <http://www.sanchem.com/electrical-contact-lubricant.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

Jeff Liebermann <jeffl@cruzio.com>: Mar 05 08:40PM -0800 On Sat, 05 Mar 2016 20:27:52 -0800, Jeff Liebermann <jeffl@cruzio.com> wrote:   >Perhaps some conductive grease would make a better connection? ><http://www.sanchem.com/electrical-contact-lubricant.html>   I forgot the data sheet: <http://www.sanchem.com/docs/NO-OX-ID%20A-Special%20WW.pdf?r=false> eBay link: <http://www.ebay.com/sch/i.html?_nkw=no-ox-id> and MSDS: <http://www.northtowncompany.com/pdfs/no-ox-id%20a%20special%20msds.pdf>   -- 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

DaveC <not@home.cow>: Mar 05 09:10PM -0800 Jeff Liebermann wrote:   > Dielectric means "insulator" in this case, which is not exactly what I > would want in an RF connector.   Jeff, I think he means he uses it under the boot, not inside the connector…   Dave

N_Cook <diverse@tcp.co.uk>: Mar 06 08:13AM On 05/03/2016 17:14, DaveC wrote: > contra-indicated.   > What say y'all?   > Thanks.   Over the years all those problematic radio multiway wavechange and tape recorder play/record slide switches. I never saw grease inside them and the failure was due to black corrossion product copper suplphide? which is an insulator that a phosphor bronze contact could not wipe/break through to make contact. The worst black was at the more open ends to the air, rather than the core of the switch body.

Bruce Esquibel <bje@ripco.com>: Mar 06 12:47PM > You put it inside the boot but not inside the connector (not inside the > F-conn), right?   Actually when home satellite systems (c/ku band) were common, filling up the F connector and the boot was a common practice when attaching the cables to the lnb's.   The general logic was, there was a zero chance of water getting in anywhere and also removed the chance of oxidation.   I don't remember what they used but I remember that guy Shaun Kenny selling it on that Boresight show for that specific reason.   -bruce bje@ripco.com

DaveC <not@home.cow>: Mar 05 08:17PM -0800 Found it on electrotanya.com   That would be elektrotanya.com   For the record...

Mike Tomlinson <mike@jasper.org.uk>: Mar 05 07:58PM En el artículo <b04ec4db-a196-4f77-948d-2ea089e763df@googlegroups.com>,   >Well, when I put the diode in correctly (per the schematic), the hum reduced >greatly   Ignore Phil, he's a thick Australian* cunt. You're doing fine, carry on as you are.   * I do apologise for the Australians, they're the result of criminals, murderers and rapists transported to van Diemen's land and the product of enthusiastic interbreeding ever since.   -- (\_/) (='.'=) Bunny says: Windows 10? Nein danke! (")_(")

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 05 11:36PM "Mike Tomlinson" wrote in message news:tUb4h9Eepz2WFwGV@jasper.org.uk...   En el artículo <b04ec4db-a196-4f77-948d-2ea089e763df@googlegroups.com>,   >Well, when I put the diode in correctly (per the schematic), the hum >reduced >greatly   Ignore Phil, he's a thick Australian* cunt. You're doing fine, carry on as you are.   * I do apologise for the Australians, they're the result of criminals, murderers and rapists transported to van Diemen's land and the product of enthusiastic interbreeding ever since.                 Bottom line, Phil called this correctly IMHO.   No way a reversed bias diode would not have destroyed the output stage in a few seconds.         Gareth.

Phil Allison <pallison49@gmail.com>: Mar 05 05:24PM -0800 Gareth Magennis wrote:     > Bottom line, Phil called this correctly IMHO.   > No way a reversed bias diode would not have destroyed the output stage in a > few seconds.   ** Of course.   If the original 4004 was leaky, that would explain a lot.     .... Phil

"Gareth Magennis" <soundserviceleeds@outlook.com>: Mar 06 04:05AM "Phil Allison" wrote in message news:e8877c67-598c-4734-b3f7-18ec0e90580c@googlegroups.com...   Gareth Magennis wrote:     > No way a reversed bias diode would not have destroyed the output stage in > a > few seconds.   ** Of course.   If the original 4004 was leaky, that would explain a lot.     .... Phil     > Gareth.           And yes, the schematic doesn't make sense, you don't get an (apparently expected?) -65v bias from a 100v tap and a (faulty) diode.   You would, however, get rather a large amount of crossover distortion from such a tap, for as long as the caps held up.       Gareth.

"Ian Field" <gangprobing.alien@ntlworld.com>: Mar 05 06:23PM The manufacturer may have slipped up on the house coded chip.   In one unit the chip was marked; 3417WA, in the other it was marked; Esmoke33716M.   Its probably going to be hard getting Google to find just a base number with no prefix - someone might just happen to know.   Thanks for any help.

M Philbrook <jamie_ka1lpa@charter.net>: Mar 05 05:53PM -0500 In article <BuFCy.1271425$bU4.965893@fx37.am4>, gangprobing.alien@ntlworld.com says...   > Its probably going to be hard getting Google to find just a base number with > no prefix - someone might just happen to know.   > Thanks for any help.   The better thing to do is put that E device in the garbage where it belongs   No one needs them, just like the real thing, they don't need them ether...   Jamie

amdx <nojunk@knology.net>: Mar 05 06:27PM -0600 On 3/5/2016 4:53 PM, M Philbrook wrote:   > No one needs them, just like the real thing, they don't need them > ether...   > Jamie   But, how are ya gonna look cool?   Mikek

M Philbrook <jamie_ka1lpa@charter.net>: Mar 05 08:21PM -0500 In article <nbftce$6ch$1@dont-email.me>, nojunk@knology.net says...   > > Jamie   > But, how are ya gonna look cool?   > Mikek   You have to be born cool.   No amount of toys, tattos, ear rings, nose rings, tongue studs, ripped trousers, paints hanging down to the knees with or with out suspenders, mohawk died or plain, mustache: plain or handle bars, strange glasses, induced lasherations, needle sharing, drug popping, nose candy, getting beer cans and apples shot off the top of your head from a drunk friend via a bow and arrow, smoking the tires off your car, blowing the engine infront of your friends, doing the highest jumps with a bike etc,. will make you COOL..   Did I miss something ?   Now of course, If you had a dame that everyone wanted, you then maybe COOL!   Jamie

amdx <nojunk@knology.net>: Mar 05 07:57PM -0600 On 3/5/2016 7:21 PM, M Philbrook wrote:   > Now of course, If you had a dame that everyone wanted, you then > maybe COOL!   > Jamie   LOL. Mikek

Roger Blake <rogblake@iname.invalid>: Mar 06 02:20AM > But, how are ya gonna look cool?   Candy cigarettes. Those have not been banned by the nanny-staters yet.   -- ----------------------------------------------------------------------------- Roger Blake (Posts from Google Groups killfiled due to excess spam.)   NSA sedition and treason -- http://www.DeathToNSAthugs.com -----------------------------------------------------------------------------

whit3rd <whit3rd@gmail.com>: Mar 05 04:09PM -0800 > My son's dog ripped an AV cable out of his TV leaving the video and two audio RCA > connectors broken... Is there an adapter that > will convert a base band input to an HDMI output?   Don't do that. Broken connectors are easily replaced (maybe even repaired). It takes some disassembly, and soldering tools, but under an hour of labor. Adapters like you describe are about as expensive as another TV...

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