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micky <NONONOmisc07@fmguy.com>: Jul 23 08:47PM -0400 In alt.home.repair, on Fri, 23 Jul 2021 12:30:09 -0400, Clare Snyder   >>Do cars with plastic bodies, like the Saturn, give bad radio reception? > What would prompt that question? What properties of Plastic, or the >behavior of radio waves????   Actually, it's that car radios have always given me better reception than house radios have. Is it the antenna, the ground plane? What?

Michael Trew <mt999999@ymail.com>: Jul 24 12:13AM -0400 On 7/23/2021 8:47 PM, micky wrote: > Actually, it's that car radios have always given me better reception > than house radios have. Is it the antenna, the ground plane? What?   Typically better reception in the car, yes, but that all depends on the antenna set up. You can have a very good antenna at home, but one with a fault in a car. I've owned both. I'd like to build an AM loop in my attic to get better AM reception at some point.   I am very into AM radio, especially long-distance AM stations at night. I've owned cars where they seem to put no thought into the AM radio band, and it shows (sounds). Dad had a Chevy Trailblazer (2006?) where you could always hear the transmission or something interfering with the AM reception.

Phil Allison <pallison49@gmail.com>: Jul 23 10:02PM -0700 micky wrote: ===========   > Actually, it's that car radios have always given me better reception > than house radios have. Is it the antenna, the ground plane? What?   ** Car radios rely on a tuned, vertical whip antenna that has a modest ground plane - the car body. This tends to work better than a small, ferrite loopstik - partly because the car antenna is normally *outdoors*.   Also, it is common for car radios to have a tuned RF stage prior to the frequency converter and IF. So three tuned circuits instead of the usual two.   FYI they normally used inductance tuning.     .... Phil

micky <NONONOmisc07@fmguy.com>: Jul 24 10:06AM -0400 In alt.home.repair, on Sat, 24 Jul 2021 00:13:18 -0400, Michael Trew >band, and it shows (sounds). Dad had a Chevy Trailblazer (2006?) where >you could always hear the transmission or something interfering with the >AM reception.   Wow.   The '72 Buick and then the '84 Chrysler and 88 Chrysler would get perfectly here in Baltimore WRC, 980AM, in Washington, DC, a station no indoor radio, even the fancy receiver, would get at all. (I've only lost interest in that station because it changed format.)   And for decades, one car radio after another, (maybe the Buick,) Chryler and Toyota, would get WAMU, 88.5FM, (American University in DC), perfectly, when only one inside radio would get it. Even now a much different Toyota radio gets WAMU usually perfectly, when the one inside radio no longer does as well. (For a while I was reporting to the WAMU engineer when reception was good or bad, and he got it good, but months later, it got weak again sometimes. (And like I say, that's the one radio that gets it at all.)   At one point a friend gave me a nice wood "box" designed to hold a car radio, an antenna, and a DC adapter, just for the sake of using a car radio indoors, but at the same time he told me that it didnt' work for him (which is why he was giving it to me). So it seems like the difference is the metal body on cars, all but a few cars.   The urls people have posted here (before electronics.repair was added) make clear that the ground plane in the car makes a difference, and that cars without one need a special antenna cable, but a) they're mostly pushed for CB radios, b) it's not at all clear that the special antenna is as good c) when shopping for an antenna, any with ground plane provision probably make note of it, but those without do not, afaik, warn people what is missing.

Ralph Mowery <rmowery42@charter.net>: Jul 24 10:21AM -0400 In article <q76ofg9e48u9nb1k4kpouknn7vdpr704ba@4ax.com>, NONONOmisc07 @fmguy.com says... > engineer when reception was good or bad, and he got it good, but months > later, it got weak again sometimes. (And like I say, that's the one > radio that gets it at all.)   One other thing about the radio in the house is that some homes have so much metal in them , especially the aluminum siding and foil reflecting insulation that the radio signals have a hard time getting in to the house.

Ralph Mowery <rmowery42@charter.net>: Jul 24 10:26AM -0400 In article <q76ofg9e48u9nb1k4kpouknn7vdpr704ba@4ax.com>, NONONOmisc07 @fmguy.com says... > is as good c) when shopping for an antenna, any with ground plane > provision probably make note of it, but those without do not, afaik, > warn people what is missing.   For AM radios in cars, the ground plane effect is almost nill. There is some capacitance coupling from the frame to the gound, but that plays very little in the AM band. The FM antennas are often built in the windshelds and the metal of the car does not com into play there either to ammount to anything.   To be much of a ground plane at the AM band you would need a plate of around 100 feet, 200 feet would be better. Just look at how tall the AM transmitter antennas are. Those antennas have about 120 wires as long as the antenna is tall burried in the ground.

Frank <"frank "@frank.net>: Jul 24 10:41AM -0400 On 7/24/2021 10:26 AM, Ralph Mowery wrote: > around 100 feet, 200 feet would be better. Just look at how tall the AM > transmitter antennas are. Those antennas have about 120 wires as long > as the antenna is tall burried in the ground.   This is the big difference in spectra that I looked at:   https://courses.lumenlearning.com/boundless-physics/chapter/the-electromagnetic-spectrum/     Shorter wavelengths penetrate better.

micky <NONONOmisc07@fmguy.com>: Jul 24 11:11AM -0400 In alt.home.repair, on Sat, 24 Jul 2021 10:21:07 -0400, Ralph Mowery >much metal in them , especially the aluminum siding and foil reflecting >insulation that the radio signals have a hard time getting in to the >house.   I have T1-11 siding, not alumininum As to foil clad insulation, I don't think so. I've been in the walls a little bit when I put a floodlight in the outside bedroom wall. House built in '79, not cheap but not the most expensive either. Plus there is a 6-foot wide window facing DC from the bedroom, where many of the radios have been, with aluminum window frames but the frames are not very big.

micky <NONONOmisc07@fmguy.com>: Jul 24 11:16AM -0400 In alt.home.repair, on Sat, 24 Jul 2021 10:26:38 -0400, Ralph Mowery >very little in the AM band. The FM antennas are often built in the >windshelds and the metal of the car does not com into play there either >to ammount to anything.   Only one car had the antenna in the windshield. A long time ago, I can't remember which. >around 100 feet, 200 feet would be better. Just look at how tall the AM >transmitter antennas are. Those antennas have about 120 wires as long >as the antenna is tall burried in the ground.   So what can I do to get reception inside as good as what I get in the car? Especially FM. In the past year, reception for WAMU, 88.5 and C-Span, 90.1, seems to have gone downhill.

Jeff Liebermann <jeffl@cruzio.com>: Jul 24 08:38AM -0700 On Sat, 24 Jul 2021 10:06:23 -0400, micky <NONONOmisc07@fmguy.com> wrote:   >is as good c) when shopping for an antenna, any with ground plane >provision probably make note of it, but those without do not, afaik, >warn people what is missing.   I beg to differ. Nobody seems to have mentioned the bane of all MF (medium frequency) reception, RF noise. A metal ground plane (car body) does a tolerable job of isolating the AM antenna from the noise generating ignition, black boxes, and gizmos. With a plastic body, the antenna will pickup more noise from the engine.   The typical car antenna is sometimes located as far away from the noisy engine as possible and connected to the AM receiver with RG-62/u 93 ohm low-capacitance coaxial cable. There is an adjustable capacitor between the antenna and the receiver input capacitance to resonate the antenna system. The coax cable capacitance and the receiver input capacitance act as a voltage divider. The more coax cable capacitance to ground, the less signal and noise arrive at the receiver. Choose your coax cable type and length carefully.   You can have a really sensitive AM receiver, and still not be able to hear much. The threshold of sensitivity is atmospheric and man-made noise. <https://en.wikipedia.org/wiki/Atmospheric_noise> Note the graph. At 1MHz, the RF noise (mostly from thunderstorms) is huge. <https://map.blitzortung.org/#3.91/39.62/-91.39> RF noise from neon signs, motors, sparking of any kind, etc just makes it worse. If you simply build a bigger antenna, or add an RF amplifier, you increase both the desired signal and the noise proportionally. If a receiver and antenna produce some SNR (signal to noise ratio), and I add more antenna gain, or more RF amplification, the resultant SNR will be the same. In other words, a bigger antenna or a "signal booster" don't buy you anything. The trick is to somehow improve the SNR, which is not easy. See various articles on the PA0RDT mini-whip antenna for clues: <https://www.google.com/search?q=pa0rdt+mini+whip>   Car AM radios tend to have the minimum sensitivity and RF front end gain needed to function in a strong signal environment. They're not made for digging signals out of the noise. That's NOT because AM car radios are made to be inexpensive. It's because the receiver is sitting next to a very noisy car engine. Were it designed to be as sensitive as an LF or HF receiver, all you would hear is engine noise. Try it. Build yourself a BCB (broadcast band) RF amplifier and attach it to your car radio antenna input. In most cases, you'll hear your engine, pump motors, and atmospherics quite well, but the distant AM stations will still be buried under the noise.   I don't have any suggestions to improve your mobile AM reception. Well, maybe the obvious suggestion to do what you can to eliminate, move, shield, or isolate sources of RF noise. If weak AM signals magically appear when you turn off the engine, the source of the noise is obvious. The problem is that you might do a wonderful job of noise reduction on your car, such as buy a diesel, but that does nothing if you're stuck in traffic and surrounded by other noisy vehicles. Notice that the ultimate noise generator, the all electric car, usually does not come with an AM radio. For example, Tesla will sell you an optional overpriced infotainment package that includes AM: <https://electrek.co/2020/10/28/tesla-brings-back-radio-infotainment-retrofit/>   Vendors used to sell rubber grounding straps, that discharge any static buildup on the car body. That should get rid of some noise. However, I believe carbon doped car tires have largely eliminated the need for those straps.   So, to answer your question, yes a plastic body gives lousy AM reception if your engine belches lots of RF noise and your receiver is reasonably sensitive. If your receiver is stone deaf, it doesn't matter.   Good luck.   -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

Ralph Mowery <rmowery42@charter.net>: Jul 24 11:57AM -0400 In article <lebofg5ovck64gg67ed1kmdvb0va3cug2n@4ax.com>, NONONOmisc07 @fmguy.com says...   > So what can I do to get reception inside as good as what I get in the > car? Especially FM. In the past year, reception for WAMU, 88.5 and > C-Span, 90.1, seems to have gone downhill.   For in the house put up an outside antenna and feed it with coax cable.

Jeroni Paul <JERONI.PAUL@terra.es>: Jul 24 06:26AM -0700 > BVM models can demand a fair bit of money. Not all CRTs are equal but > targeting gamers into that is an easy way to turn one into some amount of > $   Yes, for gaming I definitely prefer a CRT. There is something wrong in the LCD refresh or digital processing that makes the difference. Also most CRT PC monitors allow 50Hz refresh for European games. Playing a 50Hz game forced at its right speed by the emulator in a 60Hz LCD is a jerky experience.

Jeff Liebermann <jeffl@cruzio.com>: Jul 23 11:10AM -0700 On Fri, 23 Jul 2021 08:57:43 -0700 (PDT), "jurb...@gmail.com"   >In the meantime I will be uilding an XP PC but on a better board. It is going to be fast. Wil have the 4GB RAM of course, 2 SSDs.   XP can use more than 4GB RAM if the motherboard supports PAE: <https://itstillworks.com/how-to-enable-pae-on-a-32-bit-windows-xp-10155.html> <https://www.betaarchive.com/forum/viewtopic.php?t=36597>   An SSD will work on XP, but you will have problems unless you impliment some scheme to regularly run the "TRIM" command. The TRIM command or button is usually found in the various SSD managment software that comes with the SSD (e.g. Samsung Magician). I've had problems with TRIM when using a fairly new SSD and old software that's XP compatible.   [Q] What do you get when you put a jet engine in a Volkswagen? [A] It's still a Volkswagen.   >Has all the outputs for HDMI, DVI, It will have al kinds of cool >software on it that would cost many many thousands for the new version.   Or, you could get the FOSS or Linux versions for next to nothing.   >Everyone warn of virus and all tis sit, I don't have those problems.   The old viruses are still out there. -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

Jeroni Paul <JERONI.PAUL@terra.es>: Jul 24 05:54AM -0700 > In the meantime I will be uilding an XP PC but on a better board. It is going to be fast. Wil have the 4GB RAM of course, 2 SSDs. Has all the outputs for HDMI, DVI, It will have al kinds of cool software on it that would cost many many thousands for the new version.   If it has at least 2 cores, Windows 10 LTSB works great. Note I mean the LTSB version, not the mainstream Home version that comes overloaded of useless apps. I use the LTSB version in old computers like Intel Duo core with 2Gb of RAM and it works great and lets you install up to date software like Edge and Office 2019.

"ohg...@gmail.com" <ohger1s@gmail.com>: Jul 23 12:26PM -0700 > On the side, got a Tek 561A with delayed tie and dual trace, a 422 that will ont work on 12V, also a meter with nice big characters also wil only run on 12 volts. I got aa 12 volt backup thing fo a car, or newer batteries could be put in the scope and run them both.   > Already for sale are Tek 7603 and TDS-360, both need work.   > I'll still be around.   Good luck Jeff. Hope your health improves.   Regarding the 7603, most problems are the big honking Mallory caps in the power supply. Over the past 30 years, mine has gone down 4 times, three to bad caps (last time two months ago) and one bad IC in the horiz plug in. Symptoms of those bad caps are no display or a badly distorted display.

Trevor Wilson <trevor@rageaudio.com.au>: Jul 24 08:46AM +1000 > On the side, got a Tek 561A with delayed tie and dual trace, a 422 that will ont work on 12V, also a meter with nice big characters also wil only run on 12 volts. I got aa 12 volt backup thing fo a car, or newer batteries could be put in the scope and run them both.   > Already for sale are Tek 7603 and TDS-360, both need work.   > I'll still be around.   **Damn. Good luck for the future. Pity you're not nearby (I'm in Australia), I'd grab that 7603. Nice 'scope. I salvaged a 7A22 for use in a 7000 series, when one falls in my lap.

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"jurb...@gmail.com" <jurb6006@gmail.com>: Jul 23 09:23AM -0700 Finally for good. Next month fslls on my 1st Bday, My health sucks and I can barely walk. I own amps I cannot lift. And my eyesight is shit.   Electronix Underground will be no more after August 18th 2010.   I doubt I will sell it all off. I might want to experiment. I think I got an Arduino around here somewhere.   I should sell a few things, like all these matched sets of output transistors. I am not anxious to sell the equipment. I got an HP 339a, Tek 465B, Wavetek old analog genrator, a cheapo scope for a diaaly driver, a FLuke 8850a and an 8000a, HP 5314a freq. counter, homemade isolation good to at least 1,000 watts ad dummy loads close. They'll handle the 1,000 but are only 9.1 ohms, not 8.   On the side, got a Tek 561A with delayed tie and dual trace, a 422 that will ont work on 12V, also a meter with nice big characters also wil only run on 12 volts. I got aa 12 volt backup thing fo a car, or newer batteries could be put in the scope and run them both.   Already for sale are Tek 7603 and TDS-360, both need work.   I'll still be around.

"jurb...@gmail.com" <jurb6006@gmail.com>: Jul 23 08:57AM -0700 ----- In the meantime I will be uilding an XP PC but on a better board. It is going to be fast. Wil have the 4GB RAM of course, 2 SSDs. Has all the outputs for HDMI, DVI, It will have al kinds of cool software on it that would cost many many thousands for the new version.   Everyone warn of virus and all tis sit, I don't have those problems.

Ralph Mowery <rmowery42@charter.net>: Jul 22 12:44PM -0400 In article <d6d719a3-3fcb-46cf-bd6b-cc7b3797aa20n@googlegroups.com>, peterwieck33@gmail.com says...   > This also ignores inverter losses (typically between 5 & 15% - 5% for a grid-tie type, 15% for most others).   > The inverter may be rated at 4,000 watts. There are very, very few conventional automotive-type lead-acid batteries that could sustain it.   I have often wondered why there are inverters out that convert 12 volts to much over 1000 watts. Even that is high, but it may take that to start the small motors or the input rush of other electronics.   As you pointed out it takes a very large battery to provide that much power for very long. If you are going to run an engine to keep thebattery charged, you might as well use a 120/240 volt generator in the first place.

Rheilly Phoull <rheilly@bigslong.com>: Jul 23 09:30AM +0800 On 23/07/2021 12:44 am, Ralph Mowery wrote: > power for very long. If you are going to run an engine to keep > thebattery charged, you might as well use a 120/240 volt generator in > the first place.   So Hilda there you have it, from multiple sources !!

Phil Allison <pallison49@gmail.com>: Jul 22 07:57PM -0700 Ralph Mowery wrote: =================   > I have often wondered why there are inverters out that convert 12 volts > to much over 1000 watts. Even that is high, but it may take that to > start the small motors or the input rush of other electronics.   ** These supplies use " modified sine wave" aka variable pulse width rectangular waves.   The peak voltages are the same as the usual AC supply. A lot of overload current could be avoided by having a "soft start" system.   The unit would need a "start" button that brings up the duty cycle of the output wave from zero over a few seconds.     ..... Phil

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Hilda Winkler <hildawinkler77@gmail.com>: Jul 21 03:15PM -0700 hi group, why won't a 1.0 hp wet/dry vacuum cleaner model 2010. 120v 60hz 5.5a. Work on a 4000w 110v DC - AC Power inverter ..???

Rheilly Phoull <rheilly@bigslong.com>: Jul 22 07:57AM +0800 On 22/07/2021 6:15 am, Hilda Winkler wrote: > hi group, why won't a 1.0 hp wet/dry vacuum cleaner model 2010. 120v 60hz 5.5a. Work on a 4000w 110v DC - AC Power inverter ..???   What size battery ?

Hilda Winkler <hildawinkler77@gmail.com>: Jul 21 06:38PM -0700 On Wednesday, July 21, 2021 at 7:57:41 PM UTC-4, Rheilly Phoull wrote: > On 22/07/2021 6:15 am, Hilda Winkler wrote: > > hi group, why won't a 1.0 hp wet/dry vacuum cleaner model 2010. 120v 60hz 5.5a. Work on a 4000w 110v DC - AC Power inverter ..???   > What size battery ?   12v hooked up directly to the terminals..

Rheilly Phoull <rheilly@bigslong.com>: Jul 22 10:05AM +0800 On 22/07/2021 9:38 am, Hilda Winkler wrote: >>> hi group, why won't a 1.0 hp wet/dry vacuum cleaner model 2010. 120v 60hz 5.5a. Work on a 4000w 110v DC - AC Power inverter ..???   >> What size battery ?   > 12v hooked up directly to the terminals..   As in ampere hours, can you measure the battery voltage when the load is connected ?

Rheilly Phoull <rheilly@bigslong.com>: Jul 22 10:09AM +0800 On 22/07/2021 10:05 am, Rheilly Phoull wrote:   >> 12v hooked up directly to the terminals..   > As in ampere hours, can you measure the battery voltage when the load is > connected ?   Bearing in mind that at those levels, the battery will need to supply several hundred amps for the motor to run.

Hilda Winkler <hildawinkler77@gmail.com>: Jul 22 03:35AM -0700 On Wednesday, July 21, 2021 at 10:09:56 PM UTC-4, Rheilly Phoull wrote: > > connected ? > Bearing in mind that at those levels, the battery will need to supply > several hundred amps for the motor to run.     Tested 12.4v before the load, 12.3 with the load,.

Phil Allison <pallison49@gmail.com>: Jul 22 03:39AM -0700 hildawi...@gmail.com wrote: ---------------------------------------------------- < >> .... the battery will need to supply > > several hundred amps for the motor to run.   > Tested 12.4v before the load, 12.3 with the load,.   ** Wot load ?   You said the vac did not run.       ..... Phil

Rheilly Phoull <rheilly@bigslong.com>: Jul 22 10:30PM +0800 On 22/07/2021 6:39 pm, Phil Allison wrote:   > ** Wot load ?   > You said the vac did not run.   > ..... Phil   Yeah, like Phil said ??

"Peter W." <peterwieck33@gmail.com>: Jul 22 08:39AM -0700 Mpffff.   One Horsepower = 746 watts. For now, let's ignore the starting surge. 746/110 = 6.78 Amps. That is the *AC* load for the motor when running. 746/12 = 62.2 amps from the battery to make that load.   Now, consider the starting surge (typically six (6) times the running current). That battery would need to put out +/-373 amps for the start.   This also ignores inverter losses (typically between 5 & 15% - 5% for a grid-tie type, 15% for most others).   The inverter may be rated at 4,000 watts. There are very, very few conventional automotive-type lead-acid batteries that could sustain it.   Peter Wieck Melrose Park, PA

N_Cook <diverse@tcp.co.uk>: Jul 22 08:10AM +0100 On 19/07/2021 16:54, N_Cook wrote: > lens. Just trying out a pan of water , shrouded against false returns, > to check out over 20 metres initially. For real over tidal water comes > later.   I'm way off trying to use this SPI coding , and I'm no codesmith , but for anyone else landing here, there may be an error in the 7segment/decimal conversion block   else if(c == 0x3F) decimal[i] = '0'; else if (c == 0x06) decimal[i] = '1'; else if (c == 0x6D) decimal[i] = '2'; else if (c == 0x4F) decimal[i] = '3'; else if (c == 0x56) decimal[i] = '4'; else if (c == 0x5B) decimal[i] = '5'; else if (c == 0x7B) decimal[i] = '6'; else if (c == 0x0E) decimal[i] = '7'; else if (c == 0x7F) decimal[i] = '8'; else if (c == 0x5F) decimal[i] = '9';   The hex 6D and 5B may need swapping around for the '2' and '5'   -- Global sea level rise to 2100 from curve-fitted existing altimetry data <http://diverse.4mg.com/slr.htm>

bruce bowser <bruce2bowser@gmail.com>: Jul 21 11:16AM -0700 On Wednesday, July 21, 2021 at 2:10:33 PM UTC-4, bruce bowser wrote in alt.home.repair:   > > >-- https://www.zoro.com/leviton-receptacle-duplex-20a-5-20r-125v-white-cr20-w/i/G3837374/feature-product?utm_source=google&utm_medium=surfaces&utm_campaign=shopping%20feed&utm_content=free%20google%20shopping%20clicks&gclid=CjwKCAjwi9-HBhACEiwAPzUhHN1aeMWrf55qsUBQ3ZHvrWnhINUsWGnhs_7QFx7XMobaImvzxZflLRoCDSQQAvD_BwE > > I don't think so. It's own url and label include 125V. > At peak or non-peak? Here in the 21st century we are designed to go over and under you know.   Plus, The left prong port has a horizontal port for 220 VAC 15-20A or for 120 VAC 15-20A.

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Rob <nomail@example.com>: Jul 20 10:52PM +0200 > is that I had to do the work on site instead of my former office. > Another is where the speaker cables were installed without a service > loop.   But those are faults in the installation, failure to follow procedures. That is different from faults in the DESIGN of the connectors!   Jack plugs fail even when they are installed correctly. Everone knows bad contacts with jack plugs, and the procedure to recover good contact. With RCA Phono plugs, about the same thing.   You will not have seen those issues with XLR or SpeakON.

Clifford Heath <no.spam@please.net>: Jul 21 09:20AM +1000 On 20/7/21 12:44 pm, David Farber wrote:   > Hi Jeff,   > Thanks for the links. I was able to solder the rivet to the tip and now > the connection is solid. By the way, the cable is about 8mm in diameter.   Solder is very poor as a mechanical coupling. You should at least tape it thoroughly to avoid rotational forces reaching the solder joint, it it will fail again. BTDT!   CH

Phil Allison <pallison49@gmail.com>: Jul 20 04:59PM -0700 Rob wrote: ========= > knows bad contacts with jack plugs, and the procedure to recover > good contact. With RCA Phono plugs, about the same thing.   > You will not have seen those issues with XLR or SpeakON.   ** Dodgy 1/4 inch jack connections sure are very common - mostly due to damage or corrosion of the female part on equipment. Nickel plate wears off and corrodes, plastic frame jack sockets break apart if cables get yanked hard.   But XLR and Speakon type connections are not immune - I often see ones that do not work any more. Cos there good ones and *bad* ones, famous brand examples being the former and cheap knock offs the latter.   I have seen examples where near new Speakon style 4 pin plugs failed to connect to perfectly good sockets. Also, Speakons of all kinds will snap in half if the cable is yanked hard at right angles or is otherwise impacted.   Plastic body XLR panel females are good only for so long - then become damaged, intermittent and hard to fix.   You get what you pay for and connectors subjected to regular heavy use *need* to be the more expensive types.   ...... Phil

legg <legg@nospam.magma.ca>: Jul 21 08:01AM -0400 On Tue, 20 Jul 2021 09:30:08 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >with the design of these connectors, the aviation headset industry >would have switched to something better long ago. ><https://www.google.com/search?q=PJ-055&tbm=isch>   If ever you've come across original phone jacks from before ~1960, you've seen hardware that still works into its 7th+ decade. These incorporated ring terminals and threaded machine screws with lock washers, internally.   You can make anything in a shoddy manner. Price rules.   Largest source of failure in current product - even moulded assemblies, involves lousy strain relief and physical manhandling.   RL

bruce bowser <bruce2bowser@gmail.com>: Jul 20 01:54PM -0700 On Monday, July 19, 2021 at 12:49:20 PM UTC-4, Peter W. wrote:   > With these in mind:   > Plug them in, and let them rip. Should a circuit breaker blow, you will know what is shared. Remove those shared items and start over. If both units happen to be on the same circuit, use only one (1) at a time.   > Ideally any AC line should be (at least) a dedicated 20A circuit using (at least) 12-gauge wire. Then there would be no discussion. If this is a rental, I feel her pain. If this is owned, install the dedicated circuits as-needed. They will not go to waste.   A 20A circuit max rather than a a 15A circuit max on a 240AC residential hook up.

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David Farber <farberbear.unspam@aol.com>: Jul 19 07:44PM -0700 On 7/18/2021 1:04 PM, Jeff Liebermann wrote: > If you have money to burn, Switchcraft is usually good: > <https://www.switchcraft.com/Category.aspx?Parent=42> > <https://www.switchcraft.com/Category.aspx?Parent=1253>   Hi Jeff,   Thanks for the links. I was able to solder the rivet to the tip and now the connection is solid. By the way, the cable is about 8mm in diameter.   -- David Farber Los Osos, CA

Rob <nomail@example.com>: Jul 20 01:47PM +0200 > -- > David Farber > Los Osos, CA   Jack-style plugs (no matter if 1/4" or 3.5mm) and solid, reliable connections are completly separate concepts. The only permanent solution is to use another type of plug.

David Farber <farberbear.unspam@aol.com>: Jul 20 07:33AM -0700 On 7/20/2021 4:47 AM, Rob wrote:   > Jack-style plugs (no matter if 1/4" or 3.5mm) and solid, reliable > connections are completly separate concepts. > The only permanent solution is to use another type of plug.   Point taken!   Thanks for your reply. -- David Farber Los Osos, CA

Jeff Liebermann <jeffl@cruzio.com>: Jul 20 09:30AM -0700 >Jack-style plugs (no matter if 1/4" or 3.5mm) and solid, reliable >connections are completly separate concepts. >The only permanent solution is to use another type of plug.   Good point, but not very useful. For example, I used to get about 50 XLR connector type microphone cables and extensions every year to repair from a local auditorium. About half failed because of failure to follow common sense soldering and assembly instructions. The other half were crude plastic clones of the real XLR connectors that simply fell apart. Also, some junk shielded microphone cable along with the usual creative wiring type errors: <https://en.wikipedia.org/wiki/XLR_connector> <https://www.google.com/search?q=xlr+connector&tbm=isch>   At the same time, I also got a few random speaker connector repairs using SpeakON connectors: <https://www.google.com/search?q=speakon+connectors&tbm=isch> <https://en.wikipedia.org/wiki/Speakon_connector> <<https://usa.yamaha.com/products/contents/proaudio/musicianspa/equipments/cable.html> Same problems as XLR. Bad soldering, bad assembly, and a failure to follow instructions. The problem for me with these speaker connectors is that I had to do the work on site instead of my former office. Another is where the speaker cables were installed without a service loop.   In other words, even the best connectors can be a problem.   Disorganized Drivel: 1. I'm mostly retired and don't do this kind of work any more. 2. I lost money on every cable I repaired. They take too long to repair. 3. The stage crew usually doesn't know how to solder or assemble connectors but pretends that they do. 4. AV Install Nightmares private group on Facebook. I'm not a member. <https://www.facebook.com/groups/133909986649315/> 5. Fixed wing aviation headset connectors use PJ-055 for the earphones and PJ-068 for the microphone. The PJ-055 is the same as the 1/4" connector under discussion. If there was anything inherently wrong with the design of these connectors, the aviation headset industry would have switched to something better long ago. <https://www.google.com/search?q=PJ-055&tbm=isch>   -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

"Peter W." <peterwieck33@gmail.com>: Jul 19 09:49AM -0700 No need to know what else may be plugged into the circuit, as there is much else to consider first:   a) Given a 4.9A steady-state current draw at 115 VAC, that comes to 563 watts. Less than a standard hair-dryer (~1,200 watts). No big deal, even for a 15A conventional circuit (1,725 watts). Even one that shares a few other small things. b) Given that the typical surge for a conventional AC unit is very roughly eight (8) times the steady-state, the circuit must be able to withstand a very roughly 38 amp surge. This is well within the capacities of a standard 15A or 20A circuit breaker - AS LONG AS THERE ARE NO OTHER LOADS. *And as long as the breaker is functioning properly*. c) Most recent (modern) window units come with a GFI device mounted on the plug. So there should be no intrinsic danger of fire or overheating. d) Never, ever use an extension cord with a window AC unit. Ever.   With these in mind:   Plug them in, and let them rip. Should a circuit breaker blow, you will know what is shared. Remove those shared items and start over. If both units happen to be on the same circuit, use only one (1) at a time.   Ideally any AC line should be (at least) a dedicated 20A circuit using (at least) 12-gauge wire. Then there would be no discussion. If this is a rental, I feel her pain. If this is owned, install the dedicated circuits as-needed. They will not go to waste.   Peter Wieck Melrose Park, PA

Bennett <bjprice@cal.berkeley.edu>: Jul 19 11:41AM -0700 On 7/19/2021 9:49 AM, Peter W. wrote:   > Ideally any AC line should be (at least) a dedicated 20A circuit using (at least) 12-gauge wire. Then there would be no discussion. If this is a rental, I feel her pain. If this is owned, install the dedicated circuits as-needed. They will not go to waste.   > Peter Wieck > Melrose Park, PA   It's easy enough to determine if the 2 sockets are on the same circuit. Plug a lamp or radio into both, then flip circuit breakers. If both devices stop, they are on the same circuit.

Phil Allison <pallison49@gmail.com>: Jul 19 04:16PM -0700 Peter Wanker puked: =================   > a) Given a 4.9A steady-state current draw at 115 VAC, that comes to 563 watts. Less than a standard hair-dryer (~1,200 watts). No big deal, even for a 15A conventional circuit (1,725 watts). Even one that shares a few other small things. > b) Given that the typical surge for a conventional AC unit is very roughly eight (8) times the steady-state, the circuit must be able to withstand a very roughly 38 amp surge.   ** But increase to 76A if both units come on together. Current 16 times over nominal has a trip time of 0.1 seconds.   ( C type breaker)   ............ Phil

Rheilly Phoull <rheilly@bigslong.com>: Jul 20 08:30AM +0800 On 20/07/2021 12:14 am, bruce bowser wrote: >>> idea to have them both on the same circuit. >> Yup, and the ratings of the circuits etc.   > Including the distance covered by the wires? from the service's interface to the outlet?   Not really, the cable should be rated for the distance which in domestic situations is not great.

"Peter W." <peterwieck33@gmail.com>: Jul 20 03:47AM -0700 Result is exactly the same. If the breaker trips - reduce/eliminate the ancillary load(s). Nor can you read for content "AS LONG AS THERE ARE NO OTHER LOADS". In the USA, C-type breakers are used in specialty applications, generally not in a residential setting. Breakers here would be, typically, type A (plain), GFCI *breaker* (as compared to a GFI *device) and AFCI breakers. Within that group are many variants that describe how they are installed. Domestic breakers are available with a "high" current setting that will allow up to 20X rating for up to one (1) full second. They are expensive. I have used them several times to support wood shops and machine shops for 'heavy' hobbyists and wood workers. Never for 'regular' stuff.   Point being that nothing changes. Plug in the units - see if the breaker trips. If it does, adjust the load accordingly. And NEVER run both at the same time.   Learn to read.   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Jul 20 04:05AM -0700 Peter W. wrote: ============ > Result is exactly the same. If the breaker trips - reduce/eliminate the ancillary load(s). > Nor can you read for content "AS LONG AS THERE ARE NO OTHER LOADS".   ** Irrelevant, my point did not need them.     > In the USA, C-type breakers are used in specialty applications,   ** Really? They the standard in every other place for GPOs.   > Domestic breakers are available with a "high" current setting that will allow up to 20X rating for up to one (1) full second.   ** Yep - that is similar to a D type.   Used where large ( or multiple) motor loads are expected.   > Point being that nothing changes. Plug in the units - see if the breaker trips. If it does, adjust the load accordingly. > And NEVER run both at the same time.   ** Yawwnnnnnnn ....   A pair of window units in two separate rooms are ** GONNA** be run on the same hot day or night !!!   You tedious fucking wanker.       ...... Phil

"Peter W." <peterwieck33@gmail.com>: Jul 20 04:09AM -0700 You always have a point. And, sadly, proper tonsorial attention is no longer an option for you.   Peter Wieck Melrose Park, PA

amdx <amdx@knology.net>: Jul 20 07:24AM -0500 On 7/19/2021 6:16 PM, Phil Allison wrote: > Current 16 times over nominal has a trip time of 0.1 seconds.   > ( C type breaker)   > ............ Phil     I had good luck with multiple freezers on one circuit breaker. I had twelve-25cuft freezers on 5 circuit breakers, over 15 years   I never had a a circuit breaker trip. I was always waiting for two freezers to start at the same time, but they never did.   I did have two freezers plugged into original house wiring, a bad connection developed at one outlet (35 years old),   this bad connection got hot enough to create an odor.   The odor came and when over a couple days before I isolated it to an outlet. When I took it apart the outlet crumble into pieces.   I was lucky to avoid a fire.                                     Mikek     -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

legg <legg@nospam.magma.ca>: Jul 20 09:29AM -0400 On Sun, 18 Jul 2021 15:32:09 -0700 (PDT), bruce bowser >> amps (115v), would overload any particular circuit. Without mapping the >> circuits, is there any way to know, other than plugging the unit in?   >What else is plugged into the circuit?   You can get an idea of what outlets are on the same branch circuit by fiddling with the fuse box an a sunny day.   Plug something noisy into the intended outlets and pull fuses till it stops.   RL

Stephen Wolstenholme <steve@easynn.com>: Jul 20 02:46PM +0100 >Plug something noisy into the intended outlets and pull fuses >till it stops.   >RL   A long time ago I had a house rewired. The fuses were clearly labeled. That has never happened since. If I was doing the job I would label the trips but I have retired.   Steve   -- http://www.npsnn.com

Jeff Layman <jmlayman@invalid.invalid>: Jul 19 06:26PM +0100 On 18/07/2021 21:15, Peter W. wrote:   > I have a very bad schematic from HiFi Engine that speaks to a shield. But its origin(s) and destination(s) are not clear.   > This condition is extant on both (2x) speakers.   > Any one out there who has had experience on these beasts? Any thoughts? If not, I will treat them as landfill and flog them as-is and with a very accurate description on the usual auction site, pick-up only. Otherwise, if there is hope, I am up for the work.   If you haven't already done so, is there any point in contacting Koss? I can't see them having any spares from that time with which they could charge an exorbitant repair fee, so maybe if they've got the service manual and/or circuit diagram, perhaps they'd let you have a copy.   --   Jeff

Phil Allison <pallison49@gmail.com>: Jul 19 05:41PM -0700 Peter Wanker is 100% NUTS !! =========================   > a) No blown fuses. Fuses are not new. > b) I have not yet plugged them in. I am generally resistant to plugging in a stranger until > I understand its functions and antecedents.   ** How bizarre !     > If I were to have a diagram of the potted transformers, I would be much more sanguine about applying power.   ** FFS why ???????     > c) I can isolate the potted transformers from the rest of the system. Theoretically, I could then determine if the amps are passing audio.     ** Really? What if the transformers are push pull output ?     > d) But I would REALLY like to know what is going on inside all that elephant snot....   ** Where - inside you fat head ?     ...... Phil

Phil Allison <pallison49@gmail.com>: Jul 19 05:44PM -0700 Peter Wanker hasLOST IT !!!   ==================     > Again: I do not understand clearly what is going on or should be going on.   ** Hmmmm - nothing new there ....     > And all I have is the nameplate in terms of anticipated current.   ** Then use that info.   > I am trying to get to where I can align the actual current to the anticipated current before I apply power.   ** Not even faintly possible .     ...... Phil

Jeff Liebermann <jeffl@cruzio.com>: Jul 19 11:15AM -0700 On Sun, 18 Jul 2021 16:30:55 -0700 (PDT), Jeroni Paul   >> caused by replacing the print cartridge while the printer power was >> turned on. Notice how close the contact pads are on the cartridge:   >The cartridge is supposed to be changed with the printer on, otherwise it is parked.   True. Opening the lid will move the cartridge carrier to roughly mid travel so that the cartridges are accessible: <https://support.hp.com/us-en/document/c03747637> I don't do it that way. What I've done to reduce failures is follow the instructions to the point where cartridges are accessible. Then, pull the power plug from the AC wall receptacle, or unplug the power cord at the printer. The cartridge carrier will remain accessible and not retract. Don't leave it like this for very long as the cartridge tend to drip ink in this position. When the internal power supply capacitors have discharged (about 15 seconds), I replace the cartridges and re-apply power. Once I convinced users to use this procedure, the number of printer failures were drastically reduced. However, failures didn't go to zero. My guess(tm) is that someone didn't follow my procedure and swapped cartridges with the power applied and then lied that they did it correctly.   >Output connections are supposed to be properly current limited and if this is really what happens maybe a diode or fuse resistor went open, may be repairable.   I've tried to troubleshoot to the component level on only one such printer and failed. The lack of a schematic, difficulty identifying some parts, and the need to build extension cables so the PCB is accessible were the major problems. I suspect that access to the factory diagnostic software would have helped, but I suspect it would simply say "replace the PCB". When I can buy a used and working replacement printer on eBay for about $50 total, there's not much incentive to repair the broken printer. <https://www.ebay.com/sch/i.html?_nkw=hp+envy+4500+printer> At my previous shop rate of $75/hr, break even with a replacement used printer is 40 minutes of labor (excluding parts cost). I could not do the repair in 40 minutes.   I don't know what killed 3 or 4 of these printers, but it keeps happening. I might have some luck identifying the culprit if I had a working printer next to the broken printer to use for comparison. That's a major project which will likely cost more than it's worth.   For what it's worth, my guess(tm) is that the outputs driving the piezoelectric heads is not properly protected. Something might be shoving power back into the driver IC, possibly when a cartridge is inserted at a slight angle causing the pads on the cartridge to short two adjacent pins together. I haven't spent any time investigating this theory beyond a quick inspection which showed that it was almost possible to short adjacent contacts. Measure the pad diameter on the cartridge. Measure the gap between adjacent pins on the carrier. In theory, there is sufficient clearance, but it's VERY close.       -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

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"Peter W." <peterwieck33@gmail.com>: Jul 18 01:15PM -0700 Just to make it clear, these are Acoustech Model X *Solid State* self-powered electrostatic speakers, about two meters high (more than 6') and just under 75 cm wide.   They are silent. As in not even a pop, click or hiss. They have been so for ten (10) years. -Fuses are good. -Capacitors are good under LV test. -Relay is good. -Power Transformer is good. -Transistors are good. - There is no evidence of physical, water, or similar damage or abuse.   These were my brother's who used them for many years until he stopped. He just moved into a rather small apartment, and they had to go.   There are two (2) potted transformers that feed from the driver section onto the speaker itself. Seven (7) leads connect to the speaker. From the back left-to-right: 1. Silicon Red wire to larger potted tranny 2. Silicon Red wire to larger potted tranny 3. Small yellow wire to smaller potted tranny 4. Small blue/black wire to smaller potted tranny 5. Small black wire to smaller potted tranny 6. Small black wire to smaller potted tranny 7. Silicon Red Wire to Fat Flat Wire on speaker to smaller potted tranny   I can get continuity from 1-2 that makes sense. I can get continuity from 3 - 6 that also seem to make sense. I cannot get continuity from 7 to anywhere either on the chassis, other transformer leads nor any other point that I can trace.   I have a very bad schematic from HiFi Engine that speaks to a shield. But its origin(s) and destination(s) are not clear.   This condition is extant on both (2x) speakers.   Any one out there who has had experience on these beasts? Any thoughts? If not, I will treat them as landfill and flog them as-is and with a very accurate description on the usual auction site, pick-up only. Otherwise, if there is hope, I am up for the work.   Thanks in advance!   Peter Wieck Melrose Park, PA

Phil Allison <pallison49@gmail.com>: Jul 18 06:53PM -0700 Peter Wanker dribbled:   =================: > Just to make it clear, these are Acoustech Model X *Solid State* self-powered > electrostatic speakers, about two meters high (more than 6') and just under 75 cm wide.   ----------------------------------------------------------------------------------------   ** The model was marketed briefly by Koss in *1965*.   Each speaker was bi-amped - at a time when most SS amps used Germanium transistors. Each amplifier feeds an output transformer, to boost the voltage maybe 100 times. If the HT ( 2kV at least) supply fails, an ES speaker goes silent.   Moisture and dust ingress destroys ES speakers over time.     ..... Phil

"Peter W." <peterwieck33@gmail.com>: Jul 19 05:53AM -0700 a) All the transistors are silicon. The output devices are in-place are 2N4348 in a TO3 package. https://alltransistors.com/crsearch.php?mat=Si&struct=NPN&pc=120&ucb=140&uce=120&ueb=7&ic=30&tj=200&ft=0.8&hfe=15&caps=TO3 b) There are three (3) transformers: the main power transformer being one and verified as having no open coils and no internal shorts. c) There are two (2) potted transformers commonly connected to the main board through a single eight (8) conductor plug (Cinch-Jones). d) Of these two transformers, one appears to be HV only (two red silicon leads to the speaker). e) The other has five (5) leads to the speaker, one of which is also red silicon. And that is the one that is floating as far as I can test. f) The available schematic does NOT show a diagram of the potted transformers. If I had that, I would not be here.   Again, before I apply power for the first time in over ten years, I would like to understand what is connected to which and to explain the 7th speaker connection with no discernable ''other end".   Peter Wieck Melrose Park, PA

Rob <nomail@example.com>: Jul 19 05:13PM +0200 > Again, before I apply power for the first time in over ten years, I would like to understand what is connected to which and to explain the 7th speaker connection with no discernable ''other end".   > Peter Wieck > Melrose Park, PA   I would recommend to first forget about those transformers and their connections and focus on the power supply and amplifiers. Unless there are blown fuses, the transformers are likely OK, but the power supplies and amplifiers could suffer from bad caps or other component failure.   Likely best is to isolate the poweramp from the transformer (unplug it and replace with a resistive load, like 50 ohms) and run the amplifiers separately, watching their output on a 'scope. Check for DC setpoint of the amplifiers and see if they output the audio. When that is OK, connect the transformers and measure on their output (being careful because of the HV)

"Peter W." <peterwieck33@gmail.com>: Jul 19 08:26AM -0700 > Check for DC setpoint of the amplifiers and see if they output the audio. > When that is OK, connect the transformers and measure on their output > (being careful because of the HV)   a) No blown fuses. Fuses are not new. b) I have not yet plugged them in. I am generally resistant to plugging in a stranger until I understand its functions and antecedents. If I were to have a diagram of the potted transformers, I would be much more sanguine about applying power. c) I can isolate the potted transformers from the rest of the system. Theoretically, I could then determine if the amps are passing audio. d) But I would REALLY like to know what is going on inside all that elephant snot.... e) And the main power transformer shows no shorted windings or internal shorts, and the secondary windings make sense as to the schematic.   Peter Wieck Melrose Park, PA

Rob <nomail@example.com>: Jul 19 05:46PM +0200 >> (being careful because of the HV)   > a) No blown fuses. Fuses are not new. > b) I have not yet plugged them in. I am generally resistant to plugging in a stranger until I understand its functions and antecedents. If I were to have a diagram of the potted transformers, I would be much more sanguine about applying power.   Power them up with a light bulb in series with the mains.   I have made a special wiring harness with a male and female mains plug and a standard E27 lamp socket that allows me to insert a light bulb (40, 60, 100W) in series with any device, to reduce the maximal current. When available, use a VARIAC to slowly increase the voltage and have a multimeter attached to some point of interest (e.g. the DC output of the powersupply) to see what happens.

"Peter W." <peterwieck33@gmail.com>: Jul 19 09:14AM -0700 I have a very nice metered Variac. https://www.byan-roper.org/steve/steve-at-play/antique-electronics-and-2/heathkit-ip-5220-variable.html like that.   Again: I do not understand clearly what is going on or should be going on. And all I have is the nameplate in terms of anticipated current. I am trying to get to where I can align the actual current to the anticipated current before I apply power.   Related: I just heard from David Janzen, the son of the designer of these beasts, and still in the business. He is looking to see if he has a diagram of the potted trannys. That will be immensely helpful.   Peter Wieck Melrose Park, PA

bruce bowser <bruce2bowser@gmail.com>: Jul 18 03:32PM -0700 On Wednesday, July 14, 2021 at 4:53:53 PM UTC-4, Boris wrote in alt.home.repair: > her home. She has no idea if the units she's looking at, which draw 4.9 > amps (115v), would overload any particular circuit. Without mapping the > circuits, is there any way to know, other than plugging the unit in?   What else is plugged into the circuit?

Michael Trew <mt999999@ymail.com>: Jul 18 08:48PM -0400 On 7/18/2021 6:32 PM, bruce bowser wrote: >> amps (115v), would overload any particular circuit. Without mapping the >> circuits, is there any way to know, other than plugging the unit in?   > What else is plugged into the circuit?     Yes, you'd have to know what else is plugged in, and it's not a good idea to have them both on the same circuit.

Rheilly Phoull <rheilly@bigslong.com>: Jul 19 08:52AM +0800 On 19/07/2021 8:48 am, Michael Trew wrote:   >> What else is plugged into the circuit?   > Yes, you'd have to know what else is plugged in, and it's not a good > idea to have them both on the same circuit.   Yup, and the ratings of the circuits etc.

bruce bowser <bruce2bowser@gmail.com>: Jul 19 09:14AM -0700 On Sunday, July 18, 2021 at 8:52:20 PM UTC-4, Rheilly Phoull wrote:   > > Yes, you'd have to know what else is plugged in, and it's not a good > > idea to have them both on the same circuit. > Yup, and the ratings of the circuits etc.   Including the distance covered by the wires? from the service's interface to the outlet?

N_Cook <diverse@tcp.co.uk>: Jul 19 04:54PM +0100 On 04/02/2021 13:42, Branislav Drengubiak wrote: > Display datasheet is available www.amega.sk/brano/Displej.pdf > driver ST7567A   > code (STM32 spi client ) is www.amega.sk/brano/main.c   Interesting info , I've downloaded for later . Just got back to this tide-gauge project, the optics part of it anyway. The bored hole through the lens has to be offset from centre by the half-inch of the separation of the laser output port and the centre of the large lens. Also covering over the small inset lens, so as not to confuse the range setting procedure. Some stainless steel "reusable drinks straws" I found for guiding the laser thru the lens without side-scatter being returned to the receiving lens. Just trying out a pan of water , shrouded against false returns, to check out over 20 metres initially. For real over tidal water comes later.   -- Global sea level rise to 2100 from curve-fitted existing altimetry data <http://diverse.4mg.com/slr.htm>

Jeroni Paul <JERONI.PAUL@terra.es>: Jul 18 04:30PM -0700 > caused by replacing the print cartridge while the printer power was > turned on. Notice how close the contact pads are on the cartridge:   The cartridge is supposed to be changed with the printer on, otherwise it is parked. Output connections are supposed to be properly current limited and if this is really what happens maybe a diode or fuse resistor went open, may be repairable.

Jeroni Paul <JERONI.PAUL@terra.es>: Jul 18 04:23PM -0700 > I have a microwave from the mid 2000s that failed on me. It uses basic circuitry: transformer, diode, cap, magnetron....not an inverter type or anything fancy like that. One morning it seemed to mostly work, but the output rapidly dropped over a few minutes. No bang, no smoke. Just stopped heating.   I repaired a similar case and it was the faston type plugs did not make good electrical connection to the magnetron. I cleaned surfaces and it came back to life.

Jeff Liebermann <jeffl@cruzio.com>: Jul 18 10:00AM -0700 On Sun, 18 Jul 2021 08:28:48 -0700, David Farber >one hand, I could easily rotate the plug end with the other hand. Only >one of those loose plugs had issues with cutting out. Do all of these >plugs need replacing?   Speaker cable is usually a pair of large gauge stranded wire. The usual problem is that one strand from the bundle is not soldered in place or there's no shrink tube insulation. As the cable is moved around, that strand could short to the other speaker wire. If the 1/4" phone plug has a metal casing, it could also short to ground. Rotating the connector is just another way of rotating the cable inside the phone plug.   At the very least, resolder the connections, add shrink tube insulation if possible, look for loose wire strands, etc. If these are not possible or practical, put some insulation between the two connections on the plug.   Also, if it's a cheap phone plug, I've had problem with the rivet that holds the lug to the phone plug tip connection. They are sometimes loose. Soldering it in place fixes that problems.     -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

David Farber <farberbear.unspam@aol.com>: Jul 18 10:16AM -0700 On 7/18/2021 9:08 AM, KenW wrote: > Usually the 'tarnish' cannot be seen. Doing that now with 1/8" on an > Intel NUC computer.   > KenW   Hi KenW,   I don't think you understood my question. If I hold the plug end in one hand and the common terminal at the back end with the other hand, is it normal to be able to rotate the plug while holding the back end steady? Most of the plugs are rigid and cannot be rotated in this fashion.   Thanks for your reply. -- David Farber Los Osos, CA

David Farber <farberbear.unspam@aol.com>: Jul 18 10:59AM -0700 On 7/18/2021 10:00 AM, Jeff Liebermann wrote:   > Also, if it's a cheap phone plug, I've had problem with the rivet that > holds the lug to the phone plug tip connection. They are sometimes > loose. Soldering it in place fixes that problems.   Hi Jeff,   I think it is your closing paragraph that applies here:   Also, if it's a cheap phone plug, I've had problem with the rivet that > holds the lug to the phone plug tip connection. They are sometimes > loose. Soldering it in place fixes that problems.   The rivet is not doing its job. I'll see if resoldering it does the trick but if not...   Regarding this: > Rotating the connector is just another way of rotating the cable > inside the phone plug.   That is what's supposed to happen when the rivet is holding everything together but in this instance, you can rotate the plug without twisting anything at the opposite end. Is this a decent quality replacement plug? https://www.digikey.com/en/products/detail/neutrik/568-NP2X-B/10488987   Thanks for your reply. -- David Farber Los Osos, CA

Jeff Liebermann <jeffl@cruzio.com>: Jul 18 01:04PM -0700 On Sun, 18 Jul 2021 10:59:55 -0700, David Farber   >That is what's supposed to happen when the rivet is holding everything >together but in this instance, you can rotate the plug without twisting >anything at the opposite end.   Ideally, the rivet and tip (center) lug should NOT rotate. If you tear apart a connector (necessary sacrifice to the connector gods), you'll find that the rivet is not a separate component but rather is part of the wire that eventually goes to the connector tip (center). I can usually grab the solder lug with pliers and rotate the lug relative to the rivet with some force. However, lug should NOT be flopping around loose. Try beating on the rivet with a drift punch to get a better connection. If that doesn't play, solder the rivet to the solder lug.   >Is this a decent quality replacement plug? >https://www.digikey.com/en/products/detail/neutrik/568-NP2X-B/10488987   I have no idea. The data sheet doesn't show the internals and there's no usable photo. At $6/ea, it would seem overpriced. Also, I don't like dissimilar metals in connectors. The description has this oddity: 6.35mm (0.250", 1/4") - Headphone Phono (RCA) Plug Mono Connector Solder That's not an RCA phono plug.   In my never humble opinion, you don't need an overprice designer phone plug. Just something that was correctly assembled. Even the best of connectors might have a few rejects.   I don't know what to recommend. You didn't provide any info on cable dimensions so I can't be sure it will fit in the shell hole. Since you don't seem to need too many, buy an assortment of likely and cheap connectors and use what seems best: <https://www.ebay.com/sch/i.html?_nkw=1%2F4+in+phone+plug> If you have money to burn, Switchcraft is usually good: <https://www.switchcraft.com/Category.aspx?Parent=42> <https://www.switchcraft.com/Category.aspx?Parent=1253> -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

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