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Charles Lucas <charlesandmilly@gmail.com>: Jul 28 06:25PM -0700 On Wednesday, July 27, 2022 at 8:31:11 AM UTC-5, Anass Luca wrote:   > You had 85 lines of quote in the post to which I replied, most not > relevant to your actual added content, for only 24 lines of material > added by you.   Thank you for pointing that out. My apologies for the limited time I had and for not trimming the posts. I will keep that in mind from now on. I noticed that too. Part of all of that was learning on my part and part of it was not taking the proper time to do so. I will do my best to remember for the future.   Have a great day and thanks again.   Sincerely,   Charles Lucas

"ohg...@gmail.com" <ohger1s@gmail.com>: Jul 29 06:33AM -0700 > Thank you for pointing that out. My apologies for the > limited time I had and for not trimming the posts.   Don't sweat it. Back when usenet was actually breathing regularly, a "proper" newsreader might have been worth the money. It's unfortunate, but usenet and even dedicated web forums have suffered badly because of the dreaded Facebook, which I admit I have gravitated to. Don't sweat using the free Google interface - that's what I use.

Freethinker <freethinker@mymail.com>: Jul 29 09:55AM +0200 On 25.07.22 20:13, Peter W. wrote: > Yikes!!   > a) What is known of the Universe may be extrapolated backwards in time. All a telescope does, whatever type of radiation it observes, is look backward in time.   Well, yes and no. A Telescope does indeed see a situation as it was when the light (or radiation) started it's travel towords it. This does not mean that what we know of the unviverse can be extrapolated backwards in time. Or at least it's not the same things: if it can be done, it needs much more than a telescope.   > b) It is a pretty linear extrapolation based on the data observed to follow distributed energy back to a (probably) single point.   It may be a non linear extrapolation: we don't know. We are still trying to find out.   > c) And, this really is basic, established science based on direct observation of specific evidence that also is repeatable.   The observations are repeatable, the conclusions are only based on "best" models of which we are not certain at all.   > d) CERN has told us a great deal on how matter is formed, how it holds together, how it behaves and more.   CERN cannot tell us anything, it doesn't speak. The results of the experiments done at CERN have shown us what basic building blocks matter has and how they interact with one another, but these are far from being complete and telling us "more" than that. They even raise more questions than ansqers and this is the beauty of physical research: there's work to be done tonorrow too.   > e) It turns out that even this is predictable and repeatable. Making it also basic science.   What is?   > f) However, we still do not know what we do not know.   Exactly.   > g) Clarke's Third Law: Science, sufficiently advanced, is indistinguishable from magic.   Was, is no longer.   > 2. There is a Prime Mover that is self-aware. > 3. There is/are forces that is/are responsible/resulted in the 'big bang'. Said force/forces need not be self-aware, intelligent, self-directed, nor anything else other than (a) Force/Forces.   > Which is the simplest explanation?   I am not advocating the existence of a God nor his non-existence. I am with ohg who says you just can't prove either way, so this whole discussion is just repeating your own conviction and nothing else. It is futile to try to convince other people of your convictions, especially with "evidence" you can't have because there is just none. A lot of people have tried before and it hasn't worked yet.   What I am saying is that you clearly never studied any physics at a University. Had you done that, you would have remembered very well the moment the professor told you "We don't know if the "Big Bang" ever really occurred. It's a theory, but as of right now it's the best theory we have" (and that was about 15 years ago, when the neutrino didn't have a mass).   In other words ohg is right when he writes "scientists don't know for sure, they think it is this way".

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Hubert Aubin <hubertaubin5678@gmail.com>: Jul 25 06:44PM -0700 > Hope this is helpful.   > Sincerely,   > Charles Lucas   I don't have a mixer but tried by connecting direct to speakers but nothing happened. Also noticed that when a CD is loaded, the CD seems to speed up and slow down. Thanks, Hubert

Charles Lucas <charlesandmilly@gmail.com>: Jul 25 07:05PM -0700 > Also noticed that when a CD is loaded, the CD seems to speed up and slow down. > Thanks, > Hubert   For the purpose of clarification:   These can take speakers as well, but it has to be done differently. The mixer allows you to obtain all of the functions or modes. These devices usually require a mixer for that type of flip flop mode. If you cannot reset the device without the aid of a mixer (nor are able to obtain a mixer), you may have to clear the main microprocessor controller by depressing the relay button, or you may have to replace the relay. In extreme cases, replace the main micro. By pressing the relay button, it may mean to hold the button down until relay shuts off. There are few occasions when the momentary push is ok. I am just saying that to get out of that mode you may have to hold the relay button for a few seconds. People get confused on button presses as these things are generalized in user manuals.   Click on this link below and then read and follow the instructions. It says deactivate "flip-flop" by pushing the relay button. Make sure you are in single mode and not continuous mode when connected to speakers.   https://www.manualslib.com/manual/390980/American-Audio-Mcd-510.html?page=18   Good luck and hope this helps.   Sincerely,     Charles Lucas.

Hubert Aubin <hubertaubin5678@gmail.com>: Jul 26 06:55AM -0700 > Good luck and hope this helps.   > Sincerely,   > Charles Lucas.     Tried again as per your instructions and still same. When i press RELAY it shut off immediately......also tried holding the RELAY button for up to 20 seconds.   Other symptoms: if i press +10 tracks it will go up to 991 (even when there is only 15 track on the CD) even when the play button is flashing, if i press eject it will display OPEN but will not open, to retrieve the CD, i have to shut off the power. When i restart the eject button will work. When i insert a CD the screen shows: 01 rEAd 0.0 When i first turn the power on, all the light go on for a second then go off (this may be normal?)

Charles Lucas <charlesandmilly@gmail.com>: Jul 26 08:24AM -0700 > to retrieve the CD, i have to shut off the power. When i restart the eject button will work. > When i insert a CD the screen shows: 01 rEAd 0.0 > When i first turn the power on, all the light go on for a second then go off (this may be normal?)   I sent out a copy of the service manual for this manual to your email. The .pdf file (the 43-44 page manual) is attached to your email. This device has a myriad of logic circuits. I suggest check the circuits that drive the loop and/or the relay system. I would also make sure that in all formats, the CD's (whatever flavor they are) actually have correct focus from the laser and that they all in their different formats reading properly. You might have a laser that had gone partially bad, therefore is rendering it all bad for every other format as well, for the one format that is truly bad.   You can check laser power, verify the servo motors are ok, and even make sure the loader and unloader are timed for each deck correctly. However, you have to have correct focus on every format. These devices are multi-format read during normal operation and can even read 3" cd's (cd singles) and 5" (4.76 cm) cd's as well. All the formats very for physical reasons or and/or for format reasons (gets into concepts of what compression type is this?). In trying to chase this down and diagnose the problem, check lasers on both decks and all formats of cd's, mp3's, etc... according to what the service manual calls for. verify the laser focus is correct on each format and check laser power. Before you do any work on the logic circuits, you need to rule out anything mechanical, make sure the relay switch is not dirty or anything. You should get some sort of a result. While you're at it, make sure the drive belts are working and in good condition too.   Check your relay on and off positions, check single versus continuous, check all of those modes that are the straight-out play modes. Disengage shuffle, random, or repeat modes. You should have a straight linear playback of track one, track two, etc... to track 16...or track 22 (some oldies cd's have that many). You should get some sort of result.   If after checking these things, you need to look into the logic circuits. You'll need a logic probe to test for an on or off condition.

"Peter W." <peterwieck33@gmail.com>: Jul 26 08:29AM -0700 If the remote is wired: a) are you able to verify continuity in each conductor? b) is there any evidence - at all - of any visible damage to the connectors at either end? c) are you able to get 'under the hood' and look at any internal connections on the umbilicus? You might try tapping on each connection with a small wooden dowel and see if anything gets better.   Generally, transportation/shipping-related faults are at stress points, internal or external. So, check those.   Peter Wieck Melrose Park, PA

Charles Lucas <charlesandmilly@gmail.com>: Jul 25 07:16PM -0700 On Monday, July 25, 2022 at 12:07:29 AM UTC-5, Jeff Liebermann wrote:   > >Gotta disagree. I'm pretty sure I remember seeing alkaline > >chargers at Radio Shack 1990ish as we looked into them for > >use with our Motorola alpha numeric pagers.   I found this link that prominently says "alkaline" and the charger was made by Buddy-L. I nicknamed them "battery buddy" 30 + years ago (about 1990). Click on this link and you will see. Thanks for everything. After the conversation and my faulty memory, I thought I would do some digging. So, the link is right here. Click below.   https://www.mercari.com/us/item/m75188640508/?gclsrc=aw.ds&&utm_source=google&utm_medium=cpc&utm_campaign=16711599291&utm_content=t0&adgroup=130207367930&network=g&device=c&merchant_id=126358573&product_id=m75188640508&product_id=1645796691995&gclid=Cj0KCQjw_viWBhD8ARIsAH1mCd7avDuQlJDgVRLgiu3Xv3qdGA6kPwLn7ntr7T0bB7fFuW7glChXbpMaAuuJEALw_wcB   > PO Box 272 http://www.LearnByDestroying.com > Ben Lomond CA 95005-0272 > Skype: JeffLiebermann AE6KS 831-336-2558   I really appreciate the great conversation. This is so useful, I am archiving it for my records as I have truly learned an immense amount here. Thank you so much! I love your sense of humor too. Really great!   Have a wonderful day!   Sincerely,   Charles Lucas

Peabody <waybackNO584SPAM44@yahoo.com>: Jul 25 12:41PM -0500 ohg...@gmail.com says...   > effectively jumping out the bad LED. If it does, the > problem will fix itself until another wayward LED crops > up or if an interconnect gets resistive.   If I connect my computer to the TV via HDMI, and display a competely white (all FFs) BMP image full screen, would I be able to detect an LED that's not lighting up? Would there be a dark area on the screen, or is the failure of one LED not enough to cause a detectable darker area on the screen? When I try this, I don't see anything unusual. The display is a little darker in the corners, but I think that's normal.

"ohg...@gmail.com" <ohger1s@gmail.com>: Jul 25 10:44AM -0700 On Monday, July 25, 2022 at 1:41:31 PM UTC-4, Peabody wrote:

"ohg...@gmail.com" <ohger1s@gmail.com>: Jul 25 10:50AM -0700 On Monday, July 25, 2022 at 1:41:31 PM UTC-4, Peabody wrote: > If I connect my computer to the TV via HDMI, and display a > competely white (all FFs) BMP image full screen, would I be > able to detect an LED that's not lighting up?   Probably, but Samsung does a good job with their lens design on their back lit models. Think about it - there is a fair amount of dead space between LEDs as they're laid out and generally you don't see the individual LED illumination even on a plain white display. There will be *some* unevenness if an LED goes out, but it's generally not dramatic, but your all white bit map pattern might show it. Try different brightness settings when you're looking at it. I've also seen some older Samsungs with half the LEDs shorted and the customers didn't complain at all about the picture until one opened and shut the array down.

John Robertson <spam@flippers.com>: Jul 25 11:07AM -0700 >> competely white (all FFs) BMP image full screen, would I be >> able to detect an LED that's not lighting up?   > Probably, but Samsung does a good job with their lens design on their back lit models. Think about it - there is a fair amount of dead space between LEDs as they're laid out and generally you don't see the individual LED illumination even on a plain white display. There will be *some* unevenness if an LED goes out, but it's generally not dramatic, but your all white bit map pattern might show it. Try different brightness settings when you're looking at it. I've also seen some older Samsungs with half the LEDs shorted and the customers didn't complain at all about the picture until one opened and shut the array down.   One of my employees brought in a Samsung 55" UN55JU7100 that has a shorted primary side of the switching supply. Hard short at the output of the first bridge rectifier. Noticed a few small value caps that are slightly bulging - is there anything else to check/replace on this series other than the shorted MOSFets and suspect caps?   I'm going to suggest he add a small fan to the backside of the TV to get longer life...   Thanks!   John :-#)#   -- (Please post followups or tech inquiries to the USENET newsgroup) John's Jukes Ltd. #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3 (604)872-5757 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

"ohg...@gmail.com" <ohger1s@gmail.com>: Jul 25 12:15PM -0700 On Monday, July 25, 2022 at 2:07:23 PM UTC-4, John Robertson wrote:   > series other than the shorted MOSFets and suspect caps?   > I'm going to suggest he add a small fan to the backside of the TV to get > longer life...   No, you'll be good to go. Just change the shorted MosFets and the caps, and it should fly. If you're very unlucky, the gate driver IC might have failed but usually the fuse will blow quick enough. If the customer changed or jumped the fuse, the gate driver IC will most likely fail on AC plug in.   You don't need a fan, but they way to extend the life of these is to lower the back light setting. Any TV I repair automatically gets a small mod to reduce the back light current regardless of where the customer sets the adjustment in the picture menu. Most LED TVs use a fixed LED voltage on the high side of the array and a MosFet on the low side which controls the current. I raise the value of the MosFet Source resistor (senses current) to fool the feedback.

"Peter W." <peterwieck33@gmail.com>: Jul 25 10:02AM -0700 "Cities in Flight"   https://en.wikipedia.org/wiki/Cities_in_Flight#:~:text=Cities%20in%20Flight%20is%20a,as%20the%20%22Okie%22%20novels.   James Blish   Peter Wieck Melrose Park, PA

"ohg...@gmail.com" <ohger1s@gmail.com>: Jul 25 10:37AM -0700 On Saturday, July 23, 2022 at 4:46:53 PM UTC-4, Trevor Wilson wrote: > On 24/07/2022 4:11 am, ohg...@gmail.com wrote:   > > Agnostic here.. > **A fence-sitter. Have the courage of your convictions.     I'm not a fence sitter. I'm just honest enough to say that I don't know - but I am honest with myself. If anything, admitting I don't know takes more courage than if I were to blindly accept a theory that can't be proven. No matter how theoretical physicists spin a "big bang" theory, they can't show any evidence or create in a lab anything from a big box of nothing, and there are plenty of scientists who say this out loud. There is no more evidence for a natural big bang start to the universe than there is for a supernatural intelligent creator. In other words none. Until I see some evidence either way, my opinion won't change.         > all. Further, many of those scientists remain as believing in > intelligent design despite years of study. > **Bullshit. 'Intelligent Design' is just 'Creationsim' re-invented.     Fine, call it what you will. I always thought Intelligent Design and Creationism were the same thing but maybe there's a distinction I'm unaware of, but there are scientists who do believe in intelligent design/creationism.       >Scientists are quite certain about how the universe began, > down to within a few microseconds after the big bang occurred.   No, some *say* they know, but they don't. Any opinion they have is their own not supported by any scientific data that can even begin to explain why the universe even exists at all.   The same goes for any sky daddy. Creationists (or Intelligent Design) run into the same problem that the Big Bang folks do when explaining their side: there is no evidence to explain when and where this god appeared and what existed before him/her/it/they. Their only answer is to say that he/she/it/they always existed. That is just as unsupported in any scientific fact as Big Bang is.

"Peter W." <peterwieck33@gmail.com>: Jul 25 11:13AM -0700 Yikes!!   a) What is known of the Universe may be extrapolated backwards in time. All a telescope does, whatever type of radiation it observes, is look backward in time. b) It is a pretty linear extrapolation based on the data observed to follow distributed energy back to a (probably) single point. c) And, this really is basic, established science based on direct observation of specific evidence that also is repeatable. d) CERN has told us a great deal on how matter is formed, how it holds together, how it behaves and more. e) It turns out that even this is predictable and repeatable. Making it also basic science. f) However, we still do not know what we do not know. g) Clarke's Third Law: Science, sufficiently advanced, is indistinguishable from magic.   William of Occam suggests that one should not needlessly multiply entities.   See this as a multiple choice problem:   1. There is a "GOD" in the Christian/Muslim/Jewish model, complete/replete with all the various trappings assigned thereto. 2. There is a Prime Mover that is self-aware. 3. There is/are forces that is/are responsible/resulted in the 'big bang'. Said force/forces need not be self-aware, intelligent, self-directed, nor anything else other than (a) Force/Forces.   Which is the simplest explanation?   There are those who believe that fetal recapitulation is proof of God/Intelligent Design. There are those that believe just the opposite. Point being that evidence-in-a-vacuum leads to a potential for misinterpretation. As, both cannot be correct in the above example.   Writing for myself, I am much happier believing that I am more-or-less responsible for my state in this world - and not living at the whim of some probably malicious, certainly capricious, demonstrably not benign 'creator'.   Peter Wieck Melrose Park, PA

Jeff Liebermann <jeffl@cruzio.com>: Jul 25 11:32AM -0700 On Mon, 25 Jul 2022 10:37:03 -0700 (PDT), "ohg...@gmail.com" >> **A fence-sitter. Have the courage of your convictions.   >I'm not a fence sitter. I'm just honest enough to say >that I don't know - but I am honest with myself.   Indecision is the key to flexibility. If I were undecided and shopping around for a religion, I would go with the highest bidder. Offers of an afterlife, threats of eternal damnation, enlightenment, celestial soap opera, secret knowledge, and future intangibles seem like poor investments. I would be expected to follow a rule book and collect my prize after I die. That's not particularly appealing and seems rather risky. All that might have worked when the average life expectancy was 27 years. Today, it's 77 years and don't have the patience to wait that long.   A possible solution is autotheism or egotheism. Basically, I declare myself to be my own god, and worship myself. This has many advantages. It's economical since I retain most of my income (no tithe). There are no tedious books to read since I'll be writing my own instructions as I go along. I can keep my options open and make the final decision just before I die. If I want to reward myself, I can do that in small installments or pay for my reward with credit cards, and default after I die.   Drivel: My version of Usenet from a mildly biblical perspective: <http://www.learnbydestroying.com/jeffl/crud/genesis.txt> and Judaism for computer geeks: <https://members.cruzio.com/~jeffl/nooze/judaism.txt>       -- 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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Peabody <waybackNO584SPAM44@yahoo.com>: Jul 22 01:06PM -0500 Ok, this is the first hands-on update.   The TV arrived this morning. I hooked it up to my computer via HDMI (it was, of course, the last HDMI connector I tried) and I get audio. Running the flashlight test, I can see the icons on my desktop and any video I play on the computer. The screen is dark, but as I understand it, passing the flashlight test means the video is working, and it's the backlight that's out.   However, the owner brought his paperwork with him, and I found the invoice for the repair done in 2017. He says the symptoms were the same then as now. The invoice says they replaced the main board, #BN94-08076A. They charged $135 for the part.   I doubt I could repair the main board, but I think it's still worth taking a look. After all, I don't know that the invoice reflects what they actually did to fix it. And even if it was the main board last time, it could be something else this time.   Perhaps it will be obvious when I take the cover off, but it seems to me that one test would be to disconnnect the main board from the power board, and see if the LEDs light up. If they do, then it is the main board that's keeping the LEDs off. If they don't then it's either the power board or the LEDs. But is it possible to test what the voltage should be on the lines driving the LEDs? If the LEDs are in series, then it has to be high enough to drive all of them, so maybe 150V or more. Is that right? What I'm looking for is a way to test whether the power board is working or not. Well maybe the voltages will be printed on the board. In the videos it looks like they might be.   I'm just not clear how the LEDs are driven. Are they like the old Christmas tree lights - all in series, so if one burns out they all go dark? Or are they in parallel, or what?   Still no success finding a schematic or service manual.

"ohg...@gmail.com" <ohger1s@gmail.com>: Jul 22 11:56AM -0700 On Friday, July 22, 2022 at 2:06:13 PM UTC-4, Peabody wrote:   > I'm just not clear how the LEDs are driven. Are they like the old > Christmas tree lights - all in series, so if one burns out they all go > dark? Or are they in parallel, or what?     In *this* model, they're all in series and it's a one channel LED system - one LED or if one interconnect opens, no light.     > Still no success finding a schematic or service manual.   Samsung doesn't publish schematics anymore. Just block diagrams and wiring diagrams at best.   An easy test on this model is to unplug the harness between the main board and the power supply and plug in the AC. With the main disconnected, the on/off line pull-up resistor will put the power supply into free-run, including the LED drive. If the back light comes on, the main *or* the power supply board is bad. If the LEDs come on, post that and I'll walk you through isolating the main or the power supply.   If the LEDs don't come on with the main disconnected and the AC applied which is what I'm confident you'll find, measure between BD9101 (either side) and J858 on the top side of the board near the LED harness. Should be more than 150V-300V (depending on whether this uses 3V or 6V LEDs) there between those jumpers. If it's there or higher, the problem is inside the display - either a bad LED or open interconnect between the LED strips.   No voltage or low voltage between those points? Bad power supply.

Peabody <waybackNO584SPAM44@yahoo.com>: Jul 22 04:32PM -0500 ohg...@gmail.com says...   > comes on, the main *or* the power supply board is bad. > If the LEDs come on, post that and I'll walk you through > isolating the main or the power supply.   Ok, so the main board controls the brightness of the LEDs through some kind of PWM signal to the power board. If so, then it seems to me if the LEDs fire up when the main board is disconnected, then the main board is the problem - something is grounding that signal line. It seems the power board has proved it's ok.   But it does occur to me that if nothing else on the main board is bad, then you could replace the PWM signal with something coming out of an Arduino. :-)   > LED or open interconnect between the LED strips.   > No voltage or low voltage between those points? Bad > power supply.   Yes, that makes sense. I don't have a lab power supply, but if I could borrow one, it seems another test would be to disconnect the LED strips and reconnect them to a power supply. You could ramp up the voltage to see if the LEDs light up at some point. If they do, then they aren't the problem. If they don't, something is open.

legg <legg@nospam.magma.ca>: Jul 22 08:48PM -0400 On Fri, 22 Jul 2022 16:32:10 -0500, Peabody >supply. You could ramp up the voltage to see if the LEDs >light up at some point. If they do, then they aren't the >problem. If they don't, something is open.   Just use a voltmeter. DC's good enough for this lamp issue.   RL

legg <legg@nospam.magma.ca>: Jul 22 11:00AM -0400 On Thu, 21 Jul 2022 15:04:24 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >>bending something. It will also offer test points for >>measurement.   >>RL   You're right. It looks like only Panasonoc, Sanyo and Sony sets have a side-button power-on reset.   For Samsung audio/no image symptoms, the 'troubleshooting tree' branches out as -check LVDS connector -change tcon -change main board   Not very helpful. Unlikely it's a power supply issue, but bulging caps are common, even so, on sets of this era.   Some TVs are too smart for their own good.   Haven't had one for personal use since 1978. Bloody waste of time.   RL

Peabody <waybackNO584SPAM44@yahoo.com>: Jul 23 08:26AM -0500 ohg...@gmail.com says...   > In *this* model, they're all in series and it's a one > channel LED system - one LED or if one interconnect > opens, no light.   On the ShopJimmy page for this model, it shows the LED package as seven strips of eight LEDs, plus seven strips of five LEDs. That's 91 LEDs. If they're all in series, then 3V LEDs would need 273V. So perhaps the strips are wired in some parallel configuration?   I'm starting on the diagnostics this morning with a neighbor who I discovered used to work for TI back in the day.   One of the ShopJimmy videos say flatly that if you pass the flashlight test, with audio, then a dark screen is either the power board or the LEDs. I guess that's not absolutely always true, but seems logical to me. I'm hoping for the power supply to be the problem. I'm not sure I would be willing to tackle the LEDs. I've watched those videos, and it's a major undertaking, with lots of opportunities to break things.

Adrian Caspersz <email@here.invalid>: Jul 23 02:36PM +0100 On 22/07/2022 03:31, Charles Lucas wrote:   > https://www.samsung.com/ca/support/model/UN55HU6840FXZC/   > Click on the Manuals and downloads link on the menu selection you can choose > from.   Unlikely :(   -- Adrian C

Peabody <waybackNO584SPAM44@yahoo.com>: Jul 23 11:33AM -0500 Well, I had a major setback trying to diagnose the repair. Last night I set it on the dining room table, face down, and this morning I did the flashlight and audio test again before even taking the back cover off, just to confirm the video and audio were still working. But after about 30 minutes, the TV started working again. All the backlights came on, and the picture is perfect. This is the behavior the owner reported - it might get backlight at any time, or it might not.   I measured 267V between BD9101 and J858, so that's the benchmark in case it dies again.   So I don't know how you diagnose anything when it's working properly. We tried tapping on every part and connector on the power board, but not even a flicker in the lights.   Both sides of the power board look perfect - not a hint of a bad solder, no domed capacitors, no brown marks. The connector to the LEDs (CLN802) has 7 black wires and one blue wire, and a legend that doesn't seem to match the connector.   In any case, I will let it cool down, and see how it powers up. I guess I could remove and test all the electrolytics, but there are a lot of them. Same for the diodes. But it seems it could be anything. Major bummer that it's working. :-)

Hubert Aubin <hubertaubin5678@gmail.com>: Jul 23 04:08AM -0700 Hello all..my American audio MCD 510 will not read Cds Will not read Cds therefore not play...on both CD player..the CDs turn ...also when remote is connected the eject buttons on base will not work but it does when the remote is not connected. Could it be a faulty remote cable?

"Peter W." <peterwieck33@gmail.com>: Jul 23 07:20AM -0700 > Hello all..my American audio MCD 510 will not read Cds > Will not read Cds therefore not play...on both CD player..the CDs turn ...also when remote is connected the eject buttons on base will not work but it does when the remote is not connected. Could it be a faulty remote cable?   Are both decks not working? Did this happen all at once?

Adrian Caspersz <email@here.invalid>: Jul 22 07:55PM +0100 On 22/07/2022 03:50, Charles Lucas wrote: > A frequent responder here asked me about my motives for coming on here and posting my remarks on a use net post. So, I thought I would answer that question.   Charles,   You are new to this.   Can you find a proper Usenet client and service? Some are free, respond back if you need pointers.   Necroposting is a waste of peoples time, and is likely to get you killfiled, flammed or ignored. Many block google-groups for that display of inaneness you've shown answering dead posts. It's bad netiquette.   If you must use google groups (and it is a poor display of tech ability if you can't even work that out) then please check the posting date of what you are (probably wasting our) time replying to.   -- Adrian C

Trevor Wilson <trevor@rageaudio.com.au>: Jul 23 05:56AM +1000 On 22/07/2022 12:50 pm, Charles Lucas wrote:   > God Bless and have a great day.   > sincerely,   > Charles Lucas     **There is no "God". Such a mythical creature violates several of the fundamental laws that govern our universe. Any person claiming some kind of technical/scientific credentials who clings to such a delusion is suspect. I suggest you do one of two things:   * Seek help for your obviously delusional problems. * Keep very quiet about your delusions.         -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

legg <legg@nospam.magma.ca>: Jul 22 05:08PM -0400 On Thu, 21 Jul 2022 19:50:26 -0700 (PDT), Charles Lucas   >God Bless and have a great day.   >sincerely,   >Charles Lucas   No harm, no foul.   Ignore anything that's irrelevent.   Effective text communication is harder than people think, but with good reading and comprehension skills, it can be the most accurate, in technical subjects (where a phone call can be a waste of time).   Though it's harder to bullshit in text coms, it's still possible - anything without references should be taken with a grain of salt.   RL

Jeff Liebermann <jeffl@cruzio.com>: Jul 22 05:35PM -0700 On Thu, 21 Jul 2022 19:50:26 -0700 (PDT), Charles Lucas   >A frequent responder here asked me about my motives for coming on here and posting my remarks on a use net post. (...) >The intent of these responses is to help others, enjoy these posts, and have the people have working, safe equipment. The intent is to do good and no intent to cause harm. I do this on my own time.   I'm more selfish. I used to like reading mystery and detective novels. It was fun trying to organize the clues and determine a likely culprit. Same with troubleshooting electronics. Usually, people who ask questions omit important information, like the model number, paraphrase error messages, inject their own pet theories, and generally make it difficult to analyze. When that happens, I suggest that they reorganize their question into a few simple questions:   1. What problem are you trying to solve? One sentence is sufficient. 2. What do you have to work with? (Maker, model, version number, options, documentation, and general condition). 3. What have you done so far and what happened? (Error messages, fire, smoke, explosion, etc). 4. What is your technical ability level and what test equipment is available?   The difficult part is getting accurate information and error messages. For reasons unknown, entering a model number from the back of a TV, or errors from a display, into a computer keyboard without errors is difficult. I frequently resort to interrogating people to get answers to simple questions. Some people will waltz around the obvious culprit, ignore the obvious and confuse descriptions by adding irrelevant drivel. It sometimes seems like I'm trying to fix the owner instead of the device. Prying information out of owners can be frustrating at times, but the results are usually worth the effort.   Hint: If you know HOW things work, you can fix anything.     -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

Stephen Wolstenholme <steve@easynn.com>: Jul 23 02:23PM +0100 On Sat, 23 Jul 2022 05:56:13 +1000, Trevor Wilson   >**There is no "God". Such a mythical creature violates several of the >fundamental laws that govern our universe.   Who made the universe? Did it need making or has it always existed?   I think we have a problem with dimensions. We only exist in four dimensions so we need a "God" to explain creation which is beyond our limitations. To get back to "electronics", maybe the universe is just a simulation.   -- Neural Network Software for Windows http://www.npsnn.com

"ohg...@gmail.com" <ohger1s@gmail.com>: Jul 22 10:03AM -0700 On Tuesday, July 19, 2022 at 3:58:55 PM UTC-4, Chris K-Man wrote:   > Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.   > Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??   > Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.   Most AM noise I've found is worse between 700KHZ - 1MHZ. At my house, the AM is almost unlistenable, and I'm in the middle of a 5 acre lot. What I found by shutting off all breakers and turning them on one by one was several items contributing to the din. I found my outdoor motion sensing light fixtures were causing noise (took them apart and hard wired them then added Honeywell wall dusk to dawn switches), my alarm system (added low value capacitors across all keyboard lines at the panel), but the biggest offender was my wifi router. I took it apart and found the PFC cap bulged and changed it. It cut the noise down but it still generates a racket.

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Peabody <waybackNO584SPAM44@yahoo.com>: Jul 20 11:01PM -0500 Friends of mine have a Samsung 55" 4K TV, model UN55HU6840 (about 2014). They say they can hear audio, but the screen is black. I'd like to take a shot at fixing it for them since they don't really have the money to buy a new one. The encouraging thing is that until recently this has been an intermittent problem that's just gradually gotten worse, and now is permanent. But I'm encouraged to think it's not burned out LEDs, else it would never have been intermittent.   I just told you everything I know about repairing TVs, but am generally experienced in electronics as a hobbyist. Based on some Youtube videos it seems I should take off the back cover and check all the connections. Then I would go to the power board and check the voltages on the lines going to the backlight LEDs, and if low, start checking diodes and electrolytics, and of course look for bad solder joints.   Does this sound like a reasonable approach? Is there a typical cause of this symptom?   I've had no luck finding a schematic. Does anyone know where I would find that?   Well, any guidance would be appreciated.

Jeff Liebermann <jeffl@cruzio.com>: Jul 20 09:45PM -0700 On Wed, 20 Jul 2022 23:01:11 -0500, Peabody   >Friends of mine have a Samsung 55" 4K TV, model UN55HU6840 (about 2014). >They say they can hear audio, but the screen is black.   Have your friend turn on the TV and pretend that it has video. Make sure he can hear the audio that goes with the video. Have him take a flashlight and illuminate an area where you know there should be a picture. No movies with dark scenes please. Have him move the flashlight around and try different angles and room lighting. If he sees anything that looks like a faint image on the screen, then the TV has an backlighting problem. That model uses LED edge lighting, so look for problems in that area. If he doesn't see anything with the flashlight, then it's a video problem. Your approach is ok, but without a service manual and a schematic, repairing a PCB might be problematic. Think about isolating the problem to a particular PCB and order a used replacement from the cannibals on eBay.   -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

Peabody <waybackNO584SPAM44@yahoo.com>: Jul 21 10:10AM -0500 Jeff Liebermann says...   > schematic, repairing a PCB might be problematic. Think > about isolating the problem to a particular PCB and > order a used replacement from the cannibals on eBay.   They've already taken it down and put it in the garage, so I'll have to do the flashlight test when they bring it to me. But I have a little more information.   This happened before, about three years ago, and they spent $250 at a local repair shop, which replaced one of the boards. But they don't know which board, and don't have the paperwork that might tell. But they say the symptoms are the same.   I found a repair video of this exact model:   https://www.youtube.com/watch?v=nhFnoLILlG4   which turned out to be bad electrolytics. I haven't done a lot of repairs, but so far pretty much all of them have been bad caps - usually high ESR. Most recently, that's two Disney coffee mug warmers and the power supply for my Ooma box. Anyway, what I'm hoping for is either a bad connection, or a bad solder joint, or some component on the power board that I can replace. I'm encouraged by the size of the components on that board - not all tiny 0201 smd, but through-hole stuff as God intended.   Well, I'm not sure anything will come of this, but I think it's worth giving it a shot. And working on stuff like this is my idea of a good time. But I would sure like to find the schematic   Film at 11.

Jeff Liebermann <jeffl@cruzio.com>: Jul 21 09:16AM -0700 On Thu, 21 Jul 2022 10:10:30 -0500, Peabody >boards. But they don't know which board, and don't have the >paperwork that might tell. But they say the symptoms are >the same.   You might be able to identify which PCB was replaced by inspecting the heads on the PCB mounting screws for wear caused by the screwdriver bit.   I don't know about your local repair shop. The lack of historical information sounds like they want you to bring the TV in for another repair instead of fixing it yourself.   In California, repair shops are required to keep records for 3 years. <https://bhgs.dca.ca.gov/laws/ear_regs.pdf> 9842. One copy shall be given to the customer and one copy shall be retained by the service dealer for a period of at least three years.   2764. Record Keeping - Customer-related Records A legible original or legible copy of the following records shall be retained by the service dealer for a period of at least three years: invoice, customer claim check, estimate records, and employee records.   If your friend paid sales tax on the parts, the shop has to keep records for 4 years.   Different states will have different rules and time periods.   -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

"ohg...@gmail.com" <ohger1s@gmail.com>: Jul 21 09:17AM -0700 On Thursday, July 21, 2022 at 12:01:15 AM UTC-4, Peabody wrote:   > I've had no luck finding a schematic. Does anyone know where I would > find that?   > Well, any guidance would be appreciated.   The HU series *does* have intermittent issues with LEDs, either from individual LEDs or the interconnects on the strips. Sometimes you can change just the bad LEDs or hardwire the interconnects if there is a voltage drop across them, but the best option is to order the complete set of strips from someone like ShopJimmy.

Tim R <timothy42bach@gmail.com>: Jul 20 05:01PM -0700 I went to replace the AA in a kitchen timer and found it had leaked out of both ends.   I think I've had more of these leak in the past year or so than in the previous ten. Is there something different in manufacture, or am I just unlucky?   I usually take batteries out of stuff I won't need right away but they've been leaking in a plastic bag anyway.

danny burstein <dannyb@panix.com>: Jul 21 12:06AM >I went to replace the AA in a kitchen timer and found it had leaked out of both ends.   >I think I've had more of these leak in the past year or so than in the previous ten. Is there something different in manufacture, or am I just unlucky?   I noticed this starting about 15 years ago. The first time was with a bunch of Sears Die Hard branded AA's and D's.   A couple of years later I ran into this with name brand Duracell and Everready.   I suspect just about all these companies now just slap their label on "cheapest supplier of the week"...     -- _____________________________________________________ Knowledge may be power, but communications is the key dannyb@panix.com [to foil spammers, my address has been double rot-13 encoded]

Jeff Liebermann <jeffl@cruzio.com>: Jul 20 08:25PM -0700 On Wed, 20 Jul 2022 17:01:36 -0700 (PDT), Tim R   >I went to replace the AA in a kitchen timer and found it had leaked out of both ends. >I think I've had more of these leak in the past year or so than in the previous ten. Is there something different in manufacture, or am I just unlucky? >I usually take batteries out of stuff I won't need right away but they've been leaking in a plastic bag anyway.   These AAA alkaline cells were made in 2007. This is what they looked like in about 2016 or 2017: <http://www.learnbydestroying.com/jeffl/crud/Kirkland-AAA-leak.jpg> Not much has changed since then. I typically purchase batteries in lots of 50 or more. I've noticed that all the batteries from a single lot act much in the same way. In other words, they all leak at the same time. With some lots, I get lucky and they never leak. Others, like those in the photos, will leak while still in the bubble package. The SoC (state of charge) doesn't seem to matter. I'm finding almost discharged and unused batteries start to leak at the same time. Temperature does make a difference. Alkaline cells stored in the refrigerator (not freezer) last longer before they leak, but will eventually leak anyway.   Over the years, I've systematically removed alkaline batteries from my equipment and replaced them with whatever is appropriate. I've had good luck with Energizer Ultimate Lithium cells. They're expensive, but so it the equipment a leaky battery will ruin. <https://www.energizer.com/about-batteries/no-leaks-guarantee> <https://www.energizer.com/about-batteries/battery-leakage>   For most everything else, I've switched to either NiMH, LiIon, or LiPo rechargeable cells. For LiIon and LiPo, I install voltage dropping diodes, a regulator IC, or something to bring the voltage down to something that won't destroy the electronics. NiMH is close enough to alkaline cell voltage that it can be used without modification.   For 9V batteries, I use the 600ma-hr LiPo rechargeable replacements: <https://www.ebay.com/itm/124977792380> Quality sucks, prices have doubled to $8/ea, but long term cost of ownership is still much better than having alkaline batteries trash my equipment. Besides being rechargeable, they LiIon and LiPo will hold their charge for a long time. It's nice having an almost fully charged battery ready when I decide to use a rarely used piece of equipment.       -- Jeff Liebermann jeffl@cruzio.com PO Box 272 http://www.LearnByDestroying.com Ben Lomond CA 95005-0272 Skype: JeffLiebermann AE6KS 831-336-2558

Bill Gill <billnews2@cox.net>: Jul 21 08:24AM -0500 On 7/20/2022 7:01 PM, Tim R wrote: > I went to replace the AA in a kitchen timer and found it had leaked out of both ends.   > I think I've had more of these leak in the past year or so than in the previous ten. Is there something different in manufacture, or am I just unlucky?   > I usually take batteries out of stuff I won't need right away but they've been leaking in a plastic bag anyway. I have had bad luck with Duracell batteries. They seem to leak when used in items that are low usage. The emergency flashlight in my bedside table and the batteries in my thermostat for example. I have had to spend quite a bit of time, off and on, cleaning contacts when I used Duracell.   Now I always use Energizer batteries. I have never had any of them leak.   Bill

Charles Lucas <charlesandmilly@gmail.com>: Jul 20 06:53PM -0700 On Wednesday, July 20, 2022 at 9:39:02 AM UTC-5, Peter W. wrote:   > It is "Aim. Ready. FIRE!". Not "FIRE!, Ready, Aim. > Peter Wieck > Melrose Park, PA Thank you for everything, Peter, sir. I understand completely where you are coming from. I shall be more judicious in the future before I respond. I realize I was all over the place on this thread (along with noting and emphasizing particular things- just things to think about, as stated before). Thank you for everything. No harm or irritation intended. Thank you for teaching me a lot here. God Bless You. Have a wonderful day.   Sincerely,   Charles Lucas

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jul 20 06:45PM -0400 Chris K-Man wrote:   > The point is, it's an issue, especially at certain parts of the AM dial, when a radio > is within 10 feet of the service mast outside my bathroom corner window. Outside > of the bathroom corner of the apt, the interference drops off exponentially.   "Doctor, doctor! It hurts when I go like this!"   "So don't go like that." ;)   Cheers   Phil Hobbs

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Charles Lucas <charlesandmilly@gmail.com>: Jul 19 02:07PM -0700 On Tuesday, July 19, 2022 at 5:58:30 AM UTC-5, Peter W. wrote:   > Now, you want some irony? About 30 years ago, I was involved in a forensic investigation of a residential fire in a house built in 1795, but fully upgraded over the years. The owner had just upgraded his 100A service to a 200A service so as to install central AC, and also a brand new whole-house fire alarm, with all the bells, whistles, devices and so forth that were current in the 1990s. Local code then required that said fire alarm be powered directly from the mains, without a fuse or breaker. So, what did our clever electrician do? He connected the feed to the alarm (Copper) into the mains at the lugs (Aluminum). This being a fairly standard house in Chestnut Hill, PA, the basement was typically damp. Well, the aluminum started to talk hard to the copper, and between the two of them, sparks started to fly. *POOF*. Took a mere 45 days from installation. The 200A Panel was a puddle of steel on the floor. The fire got hot enough to ignite 200-year-old rough-sawn SLYP joists. Not easy. And, once they get started, they go. > Peter Wieck > Melrose Park, PA   Hi there, sir. Thank you for your more civil reply. I truly appreciate that. I want you to know I do care and I am trying to work on the areas where Imyself have flaws. I at least recognize I have them. I mean no harm and truly mean well. Also, the traumatic events of the fire I witnessed at myhouse is not one of those things that kept me down. The event motivated me to help other people to be safe and aware of things to keep themsafe. So, I am allowing (and I believe the good lord is allow it too) to take a really bad situation from my childhood to allow others to benefitfrom it, just by talking about it. I do this because no one thinks it can happen to them until it does. As an old saying goes, an ounce of preventionis worth a pound of cure. I get your point on the first sentence, but you can please refrain from any further sarcasm now. I get you. Please bear in mind, I am doing this onmy own time too. I have no intention of wasting anyone's time. I stand corrected on any mistakes. Life is too short to go on with all of the thingsthat won't work all of the time, although it is okay to mention it once in a while. According to other sources, it had been said, Edison took 10,000 attempts to make the light bulb. We talk about what works to make it right. We do not talk about the other 9,999 items that failed. I touched on some points that were not germain to the conversation by merely adding those other things in (as suggestions), without mentioning fire extinguishers and classes (because usually people ask for more info. on that) as types of fire extinguishers are certainly fairly well publicized and people are educated about that. On the other hand, people are not as well educated about smoke alarms or fire alarms. Everyone seems to think they have tobuy a 10 buck fire alarm and a 5 dollar 9 volt battery and put up with the thing sounding off every single time you cook on a stovetop or bake fromthe oven as some smoke emits from those appliances (causing alarms to sound off with a 100 dB siren). The rest of the material is very interesting and educational. Thank you. I learned a lot with it all. Very Good. Seems like you're a chief inspectorto know that much about fire protections, performance, etc... I mentioned the things I mentioned because I have never been there to thestate of Pennsylvania (know of friends who have). From what I know about the state, it was one of the original 13 colonies (in fact it was the2nd state- only behind the state of Delaware- to ratify the constitution), it has a lot of history. The history made me think of old buildings andtherefore, this jarred my mind to bring up a lot of other things about fire protection. I truly appreciate your anecdote about the 200A panel and the lug nuts, each made from a different metal composition. Very interesting, aswere the effects. The outcome was very unfortunate. Things were made better 200 years ago when it came to fine carpentry. I appreciate that. I am sure finding things that are 200 years old these days is very difficult and much harder than it was in the past someyears ago earlier in our lifetime. Thank you very much for your really valuable information.   Sincerely,   Charles Lucas

Bennett <bjprice@cal.berkeley.edu>: Jul 19 04:48PM -0700 On 4/5/2022 7:20 PM, Aoli wrote: > it that would in-line wire power to the fan but I do not know what they > are called or where to find them.   > I used to live in a house that had that setup.     I'm curious - in case of a house fire do you want the attic fan to pull out the smoke or stop pulling in fresh air?

"Peter W." <peterwieck33@gmail.com>: Jul 20 03:36AM -0700 > I'm curious - in case of a house fire do you want the attic fan to pull > out the smoke or stop pulling in fresh air?   The very last thing that wants to happen is to introduce additional oxygen to the fire. An operating exhaust fan does exactly that, as well as establishes a 'flue'. Neither a good thing.   Peter Wieck Melrose Park, PA

"Peter W." <peterwieck33@gmail.com>: Jul 20 07:38AM -0700 Charles:   One more try. And I will try not to be snarky. This is a discussion group with a focus on problem-solving with an electronics emphasis. It is also, perforce, done at at distance. Often the initiator of a discussion is not only on another continent, but also subject to different codes, a different environment, and often very different basic systems. Given that this venue is also frequented by those passing as, or attempting to pass as human, with all the associated foibles, peculiarities, assumptions and backgrounds (good, bad and indifferent), there will be the occasional outlier when it comes to advice given.   Generally, >I< attempt to: a) understand the question. b) understand the asker's purpose for the question. c) attempt to clarify my understanding if not immediately clear.   Note, I write ONLY for myself. I do not write HOLY WRIT, although I try to be reasonably apt in my advice. And in most aspects of things discussed here, there are many who are vastly more experienced than I.   With all that in mind, only then will I offer advice, and only then to the extent that it is (in my experience/opinion) useful. I was not being snarky at all when I wrote: "... that this venue exists to provide overly complex solutions to simple problems after extensive discussions of picayune and irrelevant issues." That is one of the side-effects of Usenet - that there are those who feel it necessary to not only address the nits, but pick at them as well.   >>So. Let's start with the OP: I have an whole house fan and I want to put a fire shutoff device above >>it that would in-line wire power to the fan but I do not know what they >>are called or where to find them.   At the present moment, I work in a 600,000 s.f. (557,740 s.m.) medical research facility that is 100% fresh air throughout. So, whereas there no true return-air fans, but exhaust fans. Each one of them (14 in total) has an in-duct smoke detector that will shut it off should it trip. It will _ALSO_ shut off the associated air-handler. The system as a whole moves 46,200,000 c.f. (1,308,238 c.m.) of air per hour (7 changes, on average). Altogether, even if a 50-year-old system, pretty sophisticated and within current codes. So, yes, I understand the wish behind the OP's request. And even though this is a BIG system, I have worked with smaller systems as well. And installed any number of related systems either as an owner, or holding the tools for another owner. So, I tried to give a relatable, simple, and directed answer.   I am as good as the next guy at vituperation. And at least as snarky. I admit, even, to enjoying the wordplay when the opportunity presents. In your case, however, you are putting yourself in harm's way - however sincerely - by flying off on tangents and not 'stopping' while on those flights. Nobody here minds extraneous discussions, but with the expectation that, somehow, they are a natural outflow of the thread, a thread of their own, or similar. But when one sees upwards of several dozens of posts comingling fly-poop with pepper and discussing the grain-size of same, hence the "... venue exists...." line.   Nor does anyone mind inquiring about old posts. On occasion, I have updated my own reporting long-term results of a procedure, as that may be relevant to some.   It is "Aim. Ready. FIRE!". Not "FIRE!, Ready, Aim.   Peter Wieck Melrose Park, PA

"ohg...@gmail.com" <ohger1s@gmail.com>: Jul 20 09:21AM -0700 On Tuesday, July 19, 2022 at 7:48:49 PM UTC-4, Bennett wrote:   > > I used to live in a house that had that setup. > I'm curious - in case of a house fire do you want the attic fan to pull > out the smoke or stop pulling in fresh air?   I have a whole house fan as well as central air and use the fan on any summer night when the humidity is low. We love it. But I'm ashamed to admit that it never occurred to me that a whole house fan and a fire are bad news when running together. Ever fan a flame to increase the heat? That's what moving air does, and our fan moves so much air it will slam doors to the point where we have to block bedroom doors open lest we awakened by a chorus of doors slamming (once one goes, the rest follow).   I am going to tie our central detectors to the fan to shut it down when a fire is detected. I'm glad the OP asked this question.

TTman <kraken.sankey@gmail.com>: Jul 20 11:02AM +0100 On 20/07/2022 07:53, Mike Mocha wrote: > compliant wires don't have this symptom.   > What is it and what causes it? Any theories? Thanks.   > https://imgur.com/a/OqHQV8U   Bits of melted tar maybe...       -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

"Peter W." <peterwieck33@gmail.com>: Jul 20 03:32AM -0700 > Bits of melted tar maybe...   That was (is) a potting material commonly used 'back in the day' over taped connectors. Now, my electrical experience 'in the field' goes back to 1972, and the electrician I worked for had a metal pot with a screw-lid & brush cap that he used when we ran cables to stubs in a conduit where there might be water involved. The cables would be bugged to the stubs, taped, then tarred, then taped again.   Peter Wieck Melrose Park, PA

Dan Purgert <dan@djph.net>: Jul 20 11:10AM -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512   Mike Mocha wrote: > compliant wires don't have this symptom.   > What is it and what causes it? Any theories? Thanks.   > https://imgur.com/a/OqHQV8U   If it's anything like the HV wiring in 1940s/50s era locomotives that I've worked on restoring, the insulation is essentially some kind of cloth dipped in tar (pitch, whatever).     -----BEGIN PGP SIGNATURE-----   iQIzBAEBCgAdFiEE3asj+xn6fYUcweBnbWVw5UznKGAFAmLX4r8ACgkQbWVw5Uzn KGBa2hAAqZIbvcFzPuXRMfcvEF/CZ1EhEWQ03Wt/49rP4zlsOEx2Uv+WgQZtbxVo MReEcR10cL4uXqRENQZsD6hFeMqDLE98SWG8B9U49/KZfkoeVsLu5836tAR56DZz n7L6mY842B/jElo4YxHN6SDG4oti231AkXY4kxvOrdjdM3Me9qMrYVg9fhrE+nlI OIj9b7UTus1zUYjrpt8A++9T9Jz6MOIl1IebGNtyeZWIxN/3s7AlLBpo70+j3Anj t99Lzg4e7toXPPzuLSJLKPhkxpceoALnHVrYOSfAQnrQeiNyBF89cMlLa1fc3od8 Q9FxPpHr03QSKYEqiQU/LzsghTl1gBxJQBOhERc2Hgxh83/g1Y5ViM9+QBd9/NiA aBQ7z2ReCjsXgskPeKs/g+uDJUp306jpblYcxlL9UfwptNxyTAh5aIVEOzOuJPvG Q/QW6DMhnfYA890HDmoJ3A/3ToGxwrY6b9k4XJBqsNcxS4CaajZjIjF3Vb1QK/K1 QIZDNrmzewBHMsiKUeFrulwpxb4rSYY+CeinAR5kDYp69EKgLQpNh8YA+7oaapu7 hEdlRHL4QepYl1toYqs+nkWG6BAowFSwU8f/mSoxsq58AKd4uxtFNIuytlv7gAX0 Jrtz+orxFyOVV2tOpGOEsACuZjM0Z9dBOQ5QP8WKPjsxxu0bgTw= =V/lA -----END PGP SIGNATURE-----   -- |_|O|_| |_|_|O| Github: https://github.com/dpurgert |O|O|O| PGP: DDAB 23FB 19FA 7D85 1CC1 E067 6D65 70E5 4CE7 2860

"ChrisND@privacy.net" <chrisnd@privacy.net>: Jul 20 03:40PM +0100 On 20/07/2022 07:53, Mike Mocha wrote: > compliant wires don't have this symptom.   > What is it and what causes it? Any theories? Thanks.   > https://imgur.com/a/OqHQV8U   Looks like heat damage to me! Possibly caused by resistance heating in a tarnished/corroded connection? I would disassemble, clean, grease and remake the connections. Replace any damaged cable along the way: If I am right, there will be some. If I am wrong, there may not be :-)   HTH, Chris

Mike Mocha <mocha@mailexcite.com>: Jul 20 06:53AM Hey all,   Just curious what you think about this. The photos at the link are showing large gauge wire used on a vintage 600 VDC rail vehicle. We're talking 1930's electric streetcar technology. Basically 600 VDC connected to a knife switch, then to a rotating manual controller which you partially see in the photo. The rotation of it sets up the series and parallel stages to the traction motors.   We see this weird rubber beading occurring on the outside of the older wire insulation. I'm not sure what that insulation is made of or how old it is. This only seems to occur on the older wires. The newer NFPA compliant wires don't have this symptom.   What is it and what causes it? Any theories? Thanks.   https://imgur.com/a/OqHQV8U

Chris K-Man <thekmanrocks@gmail.com>: Jul 19 12:58PM -0700 Hi!   I just moved to an apartment and wanted to keep my radio in the bathroom, same as I did in the last place I lived.   Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.   Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??   Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jul 19 04:08PM -0400 Chris K-Man wrote:   > Only problem with this place is that the main electrical drop to the building is right outside my bathroom wall, interfering with FM/AM reception.   > Is there anything I can do to alleviate this - putting a noise filter on the radio power cord, etc??   > Right at the frequency of an AM I've been listening to for years, is a loud combination buzz/screeching sound.   Maybe a variable-frequency drive for an induction motor in some HVAC blower. Those things are super bad news. Or it might just be a whole building full of SMPSes.   Cheers   Phil Hobbs   -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510   http://electrooptical.net http://hobbs-eo.com

Chris K-Man <thekmanrocks@gmail.com>: Jul 19 02:00PM -0700 On Tuesday, July 19, 2022 at 4:08:33 PM UTC-4, Phil Hobbs wrote: > Briarcliff Manor NY 10510   > http://electrooptical.net > http://hobbs-eo.com _______   It happens only to radios brought into this bathroom. Lots of static on FM, intermittent multiplex(stereo for the young uns!) and loud static and that buzzy-shriek right below 80 on the standard dial(AM).   Once the boombox is moved somewhere else in the apt, it performs like a normal set.   This is (an example of) what I can see in the upper LH corner of my bathroom window:   https://i.pinimg.com/originals/2e/3c/ce/2e3cceb1c024f799276a55ab05b44240.png   A big honkin one, twice the size of a residential service! And the closer a radio set gets to that thing, the worse it buzzes

Charles Lucas <charlesandmilly@gmail.com>: Jul 19 02:19PM -0700 On Tuesday, July 19, 2022 at 4:01:02 PM UTC-5, Chris K-Man wrote:   > https://i.pinimg.com/originals/2e/3c/ce/2e3cceb1c024f799276a55ab05b44240.png   > A big honkin one, twice the size of a residential service! And the closer a radio set gets > to that thing, the worse it buzzes   With Radio reception, you can have architectural interference in a building or a residence for a myriad of different reasons. Here, you have electrical power interference as well as other metal (including aluminum) which inhibit radio waves from travel through it. If you have a table radio or a portable, try moving the device closer to a window or area with open air. Since you moved in and the place is new, I take a portable radio (an FM radio) from a cell phone or bike radio and walk around to find out where the best reception is. This is a trial and error approach. I then due this for AM and see if and where the best reception is for AM and FM, what direction the antenna is pointed, how far away, etc...   I do this to find the best range within the dwelling. I usually add an antenna to the device (if it has a telescopic antenna, you can clip additional wire to the top of the antenna with the clamp portion of the clip being conduction and the handle being non-conductive), so you can get more range and better reception.   AM is amplitude modulation and the signal is modulated by the height (amplitude) of the radio wave. FM is frequency modulated (is wider band than AM) and uses line of sight reception. FM is in a higher band than AM. FM is shorter range and more power. AM is longer range and less power.   These concepts apply to the wireless internet as well. Key is a good open area to provide an adequate reception envelope. Good Luck and God Bless.   Sincerely,     Charles Lucas

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Jul 19 05:28PM -0400 Chris K-Man wrote:   > https://i.pinimg.com/originals/2e/3c/ce/2e3cceb1c024f799276a55ab05b44240.png   > A big honkin one, twice the size of a residential service! And the closer a radio set gets > to that thing, the worse it buzzes   Well, there's more loop area there to spray magnetic fields around than there is in the cables in the wall. The nasty high-frequency currents are probably coming from VFDs, switching supplies, and so on.   I build a lot of sensitive front end amps in instruments, so I feel your pain. You still hear people advocating for star grounds, split ground planes, and so on. Those were great in 1950, but in 2022 there's so much RF and miscellaneous hash running round that a split ground plane is as good as an antenna.(*)   Cheers   Phil Hobbs   (*) There are fairly popular antenna designs based on slots and patches in planar conductors.

Chris K-Man <thekmanrocks@gmail.com>: Jul 19 02:50PM -0700 On Tuesday, July 19, 2022 at 5:28:18 PM UTC-4, Phil Hobbs wrote:   > Phil Hobbs   > (*) There are fairly popular antenna designs based on slots and patches > in planar conductors. ______________   The point is, it's an issue, especially at certain parts of the AM dial, when a radio is within 10 feet of the service mast outside my bathroom corner window. Outside of the bathroom corner of the apt, the interference drops off exponentially.   On the ground floor is a light-industrial classification, prefabing shower doors and such. No loud hums or buzzes every time material is cut or edges chamfered. Nothing like that at all. Just a steadily increasing noise the closer one gets to that bathroom window. The radio sits on top of a toilet about 8 feet from that corner of the bathroom

Chris K-Man <thekmanrocks@gmail.com>: Jul 19 02:53PM -0700 On Tuesday, July 19, 2022 at 5:28:18 PM UTC-4, Phil Hobbs wrote:   > Phil Hobbs   > (*) There are fairly popular antenna designs based on slots and patches > in planar conductors. _______   Should an electrical service mast like the one I linked to cause that level of EMI?

ehsjr <ehsjr@verizon.net>: Jul 19 06:33PM -0400 On 7/19/2022 5:53 PM, Chris K-Man wrote: >> in planar conductors. > _______   > Should an electrical service mast like the one I linked to cause that level of EMI?   The mast itself is not the cause. It is a non conductor. It is possible there is arcing between the wires inside the mast, but that is not the mast causing the problem. If arcing is occurring, it's due to frayed insulation on the wires. And I only mention it as a possibility, not a diagnosis. Another possibility is corroded/loose "bugs" ("utility splices" on your diagram). Again, not a diagnosis, but a possibility. But either of those conditions - arcing within the mast or bad connections at the top of the mast could make one think that the mast is the cause of the problem. Take a portable radio to the utility electric meter at the service entrance and see what you hear with the radio held near the meter.   Ed

dplatt@coop.radagast.org (Dave Platt): Jul 19 04:04PM -0700 In article <f3c1f08b-2a62-4f7a-a5d5-e4f31aecaa32n@googlegroups.com>,   >Should an electrical service mast like the one I linked to cause that level of EMI?   By itself, no. It ought to be a fairly passive pass-through for AC current, with no mechanism for generating RFI. If there's a loose wire or other bad connection, it could be making noise (and possibly overheating and creating a safety hazard).   Seems to me there are two possible sources of the RFI you are suffering:   (1) Industrial equipment on that line (welders, big brush motors, switching power supplies) which are generating RFI internally and feeding it back into the mains. Here in the US, "Class A" equipment (for use in business environments) is allowed a lot more RFI leakage than "Class B" (residential), and industrial equipment is even worse.   (2) A physical fault in the mains wiring, which is causing arcing and sparking, corona discharge, and so forth. Two fairly common problems on power distribution poles are bad insulators (with electricity arcing over them) and loose or defective ground connections. Arcing in a circuit-breaker panel (e.g. a breaker going bad) could have a similar effect.   In both cases the noise can travel quite a long distance along power wiring to the point where it troubles you.   There are a few ways that can be used to track the location of a noise source or fault of this type. Corona discharges and arcs often generate a lot of ultrasonic noise, and there are ultrasound receivers with directional microphones which shift this noise down into the audible band. Arcing and corona can also generate noise up into the VHF band which can be tracked using a receiver and a directional antenna (e.g. a small hand-held Yagi). A spectrum analyzer hooked to a directional antenna can be a useful tool as you may be able to see specific noise lines bouncing up and down.

Chris K-Man <thekmanrocks@gmail.com>: Jul 19 04:12PM -0700 On Tuesday, July 19, 2022 at 7:04:47 PM UTC-4, Dave Platt wrote: > antenna (e.g. a small hand-held Yagi). A spectrum analyzer hooked to > a directional antenna can be a useful tool as you may be able to see > specific noise lines bouncing up and down. ____________________ But close to that mast, in this apartment's bathroom, is where the interference is strongest, out to perhaps a ten foot radius, which covers most of this bathroom. Beyond that, the interference is, at worst, negligible.   And I understand that the head of the service mast - the part visible above and to the left of the bathroom window, is only part of the package. I will take outside a small portable radio, and walk around within 8 feet of the meters at the base of the service mast, and see what happens at the frequency of the AM station I listen to.

Jeff Liebermann <jeffl@cruzio.com>: Jul 19 09:55PM -0700 On Tue, 19 Jul 2022 16:12:18 -0700 (PDT), Chris K-Man >a small portable radio, and walk around within 8 feet of the meters at the base of >the service mast, and see what happens at the frequency of the AM station I listen >to.   Nice job deducing the likely point of entry. If your apartment building has the usual array of smartmeters, see if the noise is also coming from one particular smartmeter. You may need to REDUCE the sensitivity of the AM radio by partially covering it with aluminum foil.   Some questions and comments:   1. Is the noise present all the time or does it go on and off? If it does one and off, try to correlate the timing with something in the area the goes on and off at the same rate.   2. Does the noise appear (in the bathroom) at every frequency on your radio? If you have an HF/SW radio, try different bands. If you have a directional BCB antenna, such as a loop or ferrite rod antenna, you might be able to find the source by direction finding.   3. If you have an oscilloscope, or a laptop with a sound card running a software oscilloscope, try to get a screen print of the AM noise. This will tell me something about what might be producing the noise. Extra credit if you an SDR dongle and can produce a spectrum analyzer output. If this is too much work (which it probably is), make an audio recording of what you're hearing on the AM receiver and post the MP3 file somewhere so we can analyze it. Try to make the recording listening to a normally blank spot on the AM dial so that you're hearing only the noise and not an AM station mixed with the noise.   4. Jumping ahead, if the noise is there 24x7 and never goes away, then you're dealing with some kind of noisy device built into the local infrastructure. Such a source is going to be difficult to find and even more difficult to get the city to fix.   5. If the noise goes away at night, my guess(tm) is you're hearing noise produced by a PV (photovoltaic) solar inverter. Most vendors have EMI/RFI reduction kits available. If you have solar panels on your roof or nearby, it might be a possible source. Something like these. Make sure there's plenty of attenuation at BCB (broadcast band) frequencies: <https://www.schaffner.com/product/emc-emi-products>   6. Check if your favored AM station is streaming on the internet or does simulcast on an FM frequency. The interference might be less and the filters more effective at 100MHz.   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

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