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Black Iccy <Daedelus@whereamIinvalid.com>: Dec 17 04:52PM +1100 irefox.exe -osint - utrl   >I've used them in modular interconnect, inside chassis, >but am begining to run out.   >RL "C:\Program Files\Mozilla Firefox\firefox.exe"

legg <legg@nospam.magma.ca>: Dec 15 05:01PM -0500 Has anyone got a name for these coaxial connectors?   http://ve3ute.ca/query/connectors.jpg   Background grid is 0.10in /2.54mm.   They're not MCX, MMCX or CRC9.   Were used quite extensively internal to RCA and other video broadband RX/TX assemblies in the 60s and 70s. External connections of the boxes was generally SMA.   I've used them in modular interconnect, inside chassis, but am begining to run out.   RL

bob prohaska <bp@www.zefox.net>: Dec 15 08:58PM > OK. With the tab at the bottom of the well shorted to the perimeter > shield it still won't boot. Resetting the NVRAM doesn't help. I'll try > re-seating the CPU. At present I have no further ideas.   Wouldn't hurt to re-seat the RAM module. My A1103 quit booting with what looked like a disk failure. After much unsucessful experimentation I noticed the DIMM was ever-so-slightly crooked.   Re-seated the RAM module and the machine booted flawlessly, and still does. I'll admit I don't remember if the case was on or off, but very likely off.   I know, correlation isn't causation, but if you're in there already....   hth,   bob prohaska

"Don" <g@crcomp.net>: Dec 17 03:05AM In sci.electronics.design Tauno Voipio <tauno.voipio@notused.fi.invalid> wrote:   <snip>   > the ramp signal.   > The output capcitors are left out of the simulation, I do > not have a mode for a reversed electrolytic.   Fantastic! Thank you for all of your hard work. It will take me a few days to digest it all. Meanwhile, my pertinent notes on UJT models are available online, at the link shown below. Among other things, it contains a 2013 usenet thread where the late Jim Thompson compares the UJT model you used with a couple of others.   https://crcomp.net/paia/ujt.php   Danke,   -- Don, KB7RPU There was a young lady named Bright Whose speed was far faster than light; She set out one day In a relative way And returned on the previous night.

"Don" <g@crcomp.net>: Dec 14 02:36AM > On 13/12/2020 3:52 pm, Don wrote: >> In sci.electronics.design piglet <erichpwagner@hotmail.com> wrote:   <snip>   > horrible. I am baffled by that 1.5mV offset, bet you can just tie the > base to ground and save two resistors.   > Also the polarity of C3 C4 C5 looks strange?   At some point there was a small ~ 1" x 4" scrap of paper included with my documentation. It was an addendum, which noted how D4 was now 5.6 V instead of 6.8 V. (A fact duly recorded on my paper schematic in ink, but missing from the PDF, which was uploaded then shared with the group.) IIRC it also said Q6, Q7 were a matched pair. Of course, the scrap of paper with irreplaceable information on it got misplaced. Nonetheless, if you seek to match Q6 and Q7 to make the pair as isothermal as possible, will this circuit do the job?   https://crcomp.net/paia/matcher.png   The D3 kludge is easy enough to grasp. But R19 and R20's eccentricity is a little too far out for me. Simonton's next generation VCO removes some unsavoriness:   https://crcomp.net/paia/4720.png   Danke,   -- Don, KB7RPU There was a young lady named Bright Whose speed was far faster than light; She set out one day In a relative way And returned on the previous night.

"Don" <g@crcomp.net>: Dec 13 03:52PM >> On Sat, 12 Dec 2020 17:54:08 -0000 (UTC), "Don" <g@crcomp.net> wrote:   >>> In sci.electronics.design jlarkin@highlandsniptechnology.com wrote: >>>> On Sat, 12 Dec 2020 07:56:15 -0000 (UTC), "Don" <g@crcomp.net> wrote:   <snip>   > kooky voltage follower Q3 Q11 Q4 - the unijunction Q2 is probably the > least nasty part of it all.   > Thats why I used the word unsavoury!   Someone elsewhere mentioned how late designer John Simonton tried to use as few parts as possible, presumably to keep the total price down. So my earlier Woz analogy may be more spot on than first realized. Woz's Breakout game design reportedly earned a bonus from Atari because it kept its chip count below 120. Supposedly way down, somewhere in the neighborhood of 50 chips, it's said. Legend has it although Atari paid the bonus (to Steve Jobs) Atari didn't understand how Woz's circuit worked.   Danke,   -- Don, KB7RPU There was a young lady named Bright Whose speed was far faster than light; She set out one day In a relative way And returned on the previous night.

Tauno Voipio <tauno.voipio@notused.fi.invalid>: Dec 12 09:19PM +0200 On 12.12.20 6.49, Don wrote: > For the time being, the Callins will be substituted with a new > electrolytic in a can.   > Danke,     There must be some audio magic inside the Callins, but I see it difficult to get any advantage in a power supply filter. If you're not happy with a garden-variety aluminum, get a tantalum one, and please, with a little more than 6V rating, as the power line is nominally 6V.   --   -TV

bruce bowser <bruce2bowser@gmail.com>: Dec 16 12:48PM -0800 On Thursday, December 10, 2020 at 1:59:02 AM UTC-5, GS wrote: > > cleanly.   > > HTH   > Goop is very strong stuff, hard to remove.   I'm now wondering if liquid nails is a neutral cure or not. I guess I've used it with pot metal or the metal of the side of a panel (not significant).

dplatt@coop.radagast.org (Dave Platt): Dec 10 04:12PM -0800 In article <a5799dfb-f0d5-4ffb-adb3-097bfa1e3b7cn@googlegroups.com>,   >Look at Dow Chemical for silicon based products that are safe for electronics...I used some of their products in a similar application many many >moons ago...damn if I can remember the product numbers...   Dow 3145 is one such. You won't like the price very much, but it's MIL-spec'ed for this sort of purpose.   Dow's Dowsil 737 is a neutral-cure which seems of a similar nature - not a MIL-spec reference, but it's much more affordable.

gregz <zekor@comcast.net>: Dec 10 06:58AM > and let it dry, to see if it can be peeled off > cleanly.   > HTH   Goop is very strong stuff, hard to remove.   Greg

gregz <zekor@comcast.net>: Dec 10 06:58AM > ** Just get one labelled " Neutral Cure "   > These are safe to use with metals like copper and tin.   > ..... Phil   I tried some on copper once to test. If anything acid cleans copper. After evaporation no action exists, which is minimal time.   Greg.

Andy Burns <usenet@andyburns.uk>: Dec 09 09:49PM Jeff Liebermann wrote:   > Won't work with XT60. Gold plated connectors are made for "dry" loads > and cannot be "switched" with current flowing. You'll blow holes in > the gold plating   think even the powerpoles recommended by someone else should only be used for hot plug/unplug if you specify the silver-plated pins for them, not the standard tin-plated ones

legg <legg@nospam.magma.ca>: Dec 09 09:10AM -0500 >disconnecting needs to be made without turning off power. My manager >says the XT connectors aren't made to handle this so what could I use in >those areas instead? Thank you.   What's the voltage and current?   RL

Witherspoon <ws194@aol.com>: Dec 09 09:32AM -0500 On 12/9/20 9:10 AM, legg wrote: >> those areas instead? Thank you.   > What's the voltage and current?   > RL   Depends on the line, but generally 8-12 VDC @ up to 12 A.

legg <legg@nospam.magma.ca>: Dec 09 10:32AM -0500 >> What's the voltage and current?   >> RL   >Depends on the line, but generally 8-12 VDC @ up to 12 A.     Anderson PP15   ASMPR45-1X2-RK polarized pairs.   Digikey or others.   RL

Test Failure <test.failed@invalid.example.invalid>: Dec 09 04:06PM > test   Your test was a failure. sci.electronics.repair is not a test newsgroup.   Test articles are to be posted in newsgroups ending in *.test.

Test Failure <test.failed@invalid.example.invalid>: Dec 09 05:05PM >> newsgroup.   >> Test articles are to be posted in newsgroups ending in *.test.   > So was your reply. 3-1/2 weeks to notice?   Where do you get 3-1/2 weeks from. The OP's invalid test was posted Dec. 8 (yesterday):   Date: Tue, 8 Dec 2020 21:55:57 -0500

Tom Kupp <tjkupp@gmail.com>: Dec 09 05:42PM -0500 On 12/06/20 13:49, Jezebels_couz wrote: > Anyone here use it and what is its durability?  How about melting > temperature in warmer environments?  Thanks. Check Glyptal.

Jeff Liebermann <jeffl@cruzio.com>: Dec 16 10:25AM -0800 On Tue, 15 Dec 2020 23:30:39 -0800 (PST), Michael Terrell >> the capacitance per foot as the car coax.   >GM/Delco used RG62, which is 93 Ohms. I asked an EE from Delco about >this about 45 years ago.   See my previous posting in this thread. <https://groups.google.com/g/sci.electronics.repair/c/PNT_pCc-a3A/m/XEJLOtNnCAAJ> The AMC-62 coax is 62 ohm RG-62/u modified for American Motors Corp by replacing the small center wire with an even smaller gauge wire. I couldn't find the gauge but I do recall taking apart a broken antenna and finding what looked like 40AWG. Broken center wires were probably common: <https://www.jeepforum.com/forum/f176/radio-antenna-went-bad-how-replace-184449/> However, that was tolerated because it improved the sensitivity of the AM radio.   >lowered the sensitivity of the radio. Some had a series capacitor at >the car radio end, to lower the capacitance across the input, but >that became a voltage divider.   Yep. I remember those, but at the time, I didn't understand the implications. For a time, I was working for a 2way radio shop installing disguise antennas in law enforcement vehicles. It was common to replace the AM/FM antenna with a "disguise" 1/4 wave stainless whip antenna and RG-58c/u coax cable. I soon discovered that the replacement AM/FM antennas were the same as the "disguise" antennas, except for the connector. When I started seeing Motorola car radio connector to PL-259 adapters, and replacement antenna kits shipped without connectors, it became obvious why they were using RG-59/u. Somewhat later, car antennas with built in diplexers became available. These had ports for AM, FM, VHF, and sometimes UHF radios. With the high power 2-way radios of the day, they tended to blow up AM/FM car radios, and sometimes burn out the diplexer. They are still sold today: <http://uscomm.atwebpages.com/Embedded%20Antenna%20systems.htm>       -- 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

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