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etpm@whidbey.com: Jul 23 11:28AM -0700 In my 10 year old home I am having trouble with a couple GFCI receptacles. But I think the problem is probably with every one in the house, as they are all the same age and brand. In the bathroom when I turn off the hair clippers I use for beard trimming the GFCI almost always trips. But only when the clippers are being turned off. In the basement we have an twenty year old washing machine that we kept to use in case the upstairs new washer needed repair, which has ben more than once. When the washer changes cycles it will randomely trip the GFCI. Like the upstairs GFCI it only happens when the load is removed from the GFCI. For example, the water valve solenoids, when switched off by the washer, will cause the GFCI to trip. Or when the washer motor is turned off when it changes speed. Do I need to buy better GFCI receptacles? Or is this just because the things are generally so sensitive to arcing when a contact opens that any brand will show the same behavior/ Thanks, Eric

"pfjw@aol.com" <peterwieck33@gmail.com>: Jul 23 12:09PM -0700 > In my 10 year old home I am having trouble with a couple GFCI > receptacles. But I think the problem is probably with every one in the > house, as they are all the same age and brand.   GFCI devices have a service life of about ten (10) years in a dry location, and anywhere from 2-5 years in a damp location. In many cases, their effectiveness as a ground-fault devices is long-gone, whereas they will still function (somewhat) as a normal breaker. There are exceptions - see monthly test below.   Yes, DO test them every month as suggested. YES, DO replace them IMMEDIATELY the moment they display any sort of wonkiness.   FULL STOP.   Peter Wieck Melrose Park, PA

etpm@whidbey.com: Jul 23 04:46PM -0700 On Mon, 23 Jul 2018 12:09:48 -0700 (PDT), "pfjw@aol.com"   >FULL STOP.   >Peter Wieck >Melrose Park, PA Thanks Peter, I do test most of the GFCI receptacles monthly. They always pass. So I'll replace the two and see what happens. Eric

Jeff Liebermann <jeffl@cruzio.com>: Jul 23 06:05PM -0700 >I do test most of the GFCI receptacles monthly. They always pass. So >I'll replace the two and see what happens.   This explains what might be happening and how to troubleshoot it: <https://www.fluke.com/en-au/learn/blog/grounding/chasing-ghost-trips-in-gfci-protected-circuits> <https://www.fluke.com/en-us/product/electrical-testing/clamp-meters/fluke-369-fc> <https://www.fluke.com/en-us/product/electrical-testing/clamp-meters/fluke-368-fc>   Duz the house have aluminum wiring? I've seen similar problems caused by aluminum wiring at a friends house: <https://www.eng-tips.com/viewthread.cfm?qid=199901> We traced the problem down to loose screws on the wall outlets and GFI receptacles. Tightening everything down make the false trips disappear for about 6 months, when they came back from the dead initially on anything that drew high current. The owner then tightened down the screws again, which again fixed the problem for a few months. I think you can see where this is going. The aluminum wires were being squashed by the brass screw and cold flowing until flat with the added bonus of some galvanic corrosion in the bath and laundry rooms. In the end, he installed copper wire pigtails and anti-oxidation goop on all the outlets, which I think finally solved the problem: <https://ask-the-electrician.com/gfci-outlets-and-aluminum-wire/> <https://diy.stackexchange.com/questions/291/whats-the-best-way-of-replacing-a-plug-or-switch-in-a-house-with-aluminum-wirin>         -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

jurb6006@gmail.com: Jul 23 06:08PM -0700 Don't use them on washing machines, dryers or refrigerators.   Whatever the code says, if your house was built 10 years ago then whatever the code said then goes, or at least you can make go.   If it has a 3 prong plug and you have a properly grounded outlet you don't need it. You are not required to update except in certain cases. Just make sure the ground connections are tight.   May not quite be code but it solves the problem once and for all, and as long as those grounds are good, you will not die. Make SURE.   I read a bit and it does appear there is a little wiggle room on it, and then they say a whole 60 people died from electrical shocks last year. And then so many by fires, many more in fact. A GFCI does not protect against fires, only ground faults.   After you put regular outlets in for your 3 prong grounded appliances that have motors, do nothing. However I am not so sure about if you use those clippers in front of a sink. Too many other things can be plugged in there and the clippers are not usually 3 prong grounded, that one might have to say and either put up with it or try a newer GFCI. In that case I DO NOT recommend offing the GFCI. In fact not at all, it will solve the problem though.

Jeff Liebermann <jeffl@cruzio.com>: Jul 23 06:16PM -0700 >Don't use them on washing machines, dryers or refrigerators.   "Does Your Washing Machine Require GFCI Protection" <https://ask-the-electrician.com/does-your-washing-machine-require-gfci-protection/> The washing machine outlet itself does not require a GFCI outlet, however any outlet within 6 feet of the outside edge of the sink in laundry rooms require that it be GFCI protected.   More detail: "Do washing machines require GFCI protection?" <https://iaeimagazine.org/magazine/2012/05/16/do-washing-machines-require-gfci-protection/>     -- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558

Ralph Mowery <rmowery28146@earthlink.net>: Jul 23 11:24PM -0400 In article <165a5622-af21-4dec-a265-cf8dc7ba67e4@googlegroups.com>, jurb6006@gmail.com says...   > Don't use them on washing machines, dryers or refrigerators.   Ground faults are not used on things that must run such as refrigerators and freezers. If they trip for some reason you can loose all your stored food. I think there is a code that covers that.

tabbypurr@gmail.com: Jul 24 03:02AM -0700 > that any brand will show the same behavior/ > Thanks, > Eric   We had a thread on this very recently in sed. GFCIs are unbalanced at relatively high frequencies, the result being they tend to trip on arcing. Of course that doesn't rule out your GFCIs being faulty or substandard, or your washing machine having N-E leakage.     NT

bruce2bowser@gmail.com: Jul 24 04:29AM -0700 > GFCI devices have a service life of about ten (10) years in a dry location, and anywhere from 2-5 years in a damp location. In many cases, their effectiveness as a ground-fault devices is long-gone, whereas they will still function (somewhat) as a normal breaker. There are exceptions - see monthly test below.   > Yes, DO test them every month as suggested. > YES, DO replace them IMMEDIATELY the moment they display any sort of wonkiness.   Ha ha, 'wonkiness'.

etpm@whidbey.com: Jul 24 08:31AM -0700 On Mon, 23 Jul 2018 18:05:42 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >the problem: ><https://ask-the-electrician.com/gfci-outlets-and-aluminum-wire/> ><https://diy.stackexchange.com/questions/291/whats-the-best-way-of-replacing-a-plug-or-switch-in-a-house-with-aluminum-wirin> Thanks for the links Jeff. The house is only about ten years old and was built for us and we are the only people who have ever lived in the house. So I know the history of the house which helps. I'll check out those links today. Eric

etpm@whidbey.com: Jul 24 08:35AM -0700 >May not quite be code but it solves the problem once and for all, and as long as those grounds are good, you will not die. Make SURE.   >I read a bit and it does appear there is a little wiggle room on it, and then they say a whole 60 people died from electrical shocks last year. And then so many by fires, many more in fact. A GFCI does not protect against fires, only ground faults.   >After you put regular outlets in for your 3 prong grounded appliances that have motors, do nothing. However I am not so sure about if you use those clippers in front of a sink. Too many other things can be plugged in there and the clippers are not usually 3 prong grounded, that one might have to say and either put up with it or try a newer GFCI. In that case I DO NOT recommend offing the GFCI. In fact not at all, it will solve the problem though. The clippers are used in the bathroom so I will need to get that GFCI sorted out. Even if it means buying rechargeable clippers. The basement GFCI is also near a sink. But even if I put in another non GFCI receptacle away from the sink it will need to be connected to the same wires that feed the GFCI. I wonder if the wiring in the new receptacle before the GFCI will prevent tripping? In any case I am going to change out my old GFCIs in at least two places. Eric

captainvideo462009@gmail.com: Jul 23 02:43PM -0700 This radio had an open speaker field coil. I subbed a choke from my junk pile in place of the coil and used a PM magnet speaker. I have no idea what the specs on the OEM field coil were or those of the choke for that matter. I just grabbed something to try. The choke is about half the size of a baseball if that makes any sense. The choke came out of something God only knows what and how long ago and measures about 40 ohms. The filter, a three section twenty UF, two at 450V and one at 25 volts was replaced at some point and seems to be OK. I mention this because there is a very slight hum out of the speaker and I'm thinking that perhaps the elimination of the hum bucking coil in the OEM speaker is the cause of this. The hum isn't that bad. as soon as you turn the volume up a bit it's really not noticeable but without using another electro dynamic speaker can I do anything about this? I'm also wondering if I sized the choke properly. Does anyone have any thoughts on these two concerns? Thanks, Lenny

Ralph Mowery <rmowery28146@earthlink.net>: Jul 23 06:43PM -0400 In article <e9a48c75-2e34-4025-bcb9-d6ca6b86bbb1@googlegroups.com>, captainvideo462009@gmail.com says...   > This radio had an open speaker field coil. I subbed a choke from my junk pile in place of the coil and used a PM magnet speaker. I have no idea what the specs on the OEM field coil were or those of the choke for that matter. I just grabbed something to try. The choke is about half the size of a baseball if that makes any sense. The choke came out of something God only knows what and how long ago and measures about 40 ohms. The filter, a three section twenty UF, two at 450V and one at 25 volts was replaced at some point and seems to be OK. I mention this because there is a very slight hum out of the speaker and I'm thinking that perhaps the elimination of the hum bucking coil in the OEM speaker is the cause of this. The hum isn't that bad. as soon as you turn the volume up a bit it's really not noticeable but without using another electro dynamic speaker can I do anything about this? I'm also wondering if I sized the choke properly. Does anyone have any thoughts on these two concerns? Thanks, Lenny   Did it have a slight hum before the coil opened up ? Could be the choke is the wrong size, or unless the filter capacitors have been changed lately, they are bad, weak, or whatever you want to call it. It could even be some heater to cathode leakage in the tubes.

Phil Allison <pallison49@gmail.com>: Jul 23 09:56PM -0700 > This radio had an open speaker field coil. > I subbed a choke from my junk pile in place of the coil > and used a PM magnet speaker.   ** Doing this eliminates the hum producing mechanism present in field coil "electro-dynamic" speakers - ie the field and voice coils acting like a transformer so the voice coil is supplied with double supply frequency hum.   Hum heard with a PM speaker set up is usually due to inadequate supply filtering (not enough L or C ) and the use of singled ended triode or pentode amplifiers.   Maybe try adding a series resistor with that 40 ohms choke - say 220ohms for a start. Should only result in a few volts loss of HT.   http://www.nostalgiaair.org/PagesByModel/529/M0018529.pdf     .... Phil

tabbypurr@gmail.com: Jul 24 03:11AM -0700 > This radio had an open speaker field coil. I subbed a choke from my junk pile in place of the coil and used a PM magnet speaker. I have no idea what the specs on the OEM field coil were or those of the choke for that matter. I just grabbed something to try. The choke is about half the size of a baseball if that makes any sense. The choke came out of something God only knows what and how long ago and measures about 40 ohms. The filter, a three section twenty UF, two at 450V and one at 25 volts was replaced at some point and seems to be OK. I mention this because there is a very slight hum out of the speaker and I'm thinking that perhaps the elimination of the hum bucking coil in the OEM speaker is the cause of this. The hum isn't that bad. as soon as you turn the volume up a bit it's really not noticeable but without using another electro dynamic speaker can I do anything about this? I'm also wondering if I sized the choke properly. Does anyone have any thoughts on these two concerns? Thanks, Lenny   Check out the thread 2017 sci.electronics.repair › Ampeg (?) 15" bass speaker 5815026 and https://www.radiomuseum.org/forum/background_hum_with_electrodynamic_loudspeakers.html     NT

"pfjw@aol.com" <peterwieck33@gmail.com>: Jul 24 04:29AM -0700 Did you toss the old speaker? If not, obtain the largest electrolytic capacitor at the highest voltage to which you can charge it fully.   Discharge it across the open coil. 2/3 of the time, that discharge will be enough to re-weld the broken ends of the coil inside.   OR:   Unwind the field coil if possible. 80% of the failures are at the connections.   Otherwise, live with the hum - you are correct in that the hum-buck does not exist on the choke.   Best of luck with it.   Peter Wieck Melrose Park, PA

jaugustine@verizon.net: Jul 23 04:40PM -0400 Hi,   I have a SM for Panasonic DVD recorder model DMR-ES20EG, EP, EE.   Unfortunately, the PCB on the bottom of the mother board is VERY DIFFERENT than the PCB bottom of my DMR-ES20 mother board.   I went through 11 pages of Google "hits" looking for the SM for a "DMR-ES20" (my model) without a letter/s after "20".   I am willing to PAY for the SM.   Does anyone know of a source (in English)?   Thank You in advance, John

Jon Elson <elson@pico-systems.com>: Jul 23 01:19PM -0500 On Mon, 23 Jul 2018 11:03:51 +0100, N_Cook wrote:   > flutes for very specific registration. > But the real mystery is the box has 24 recesses for 24 keycaps , A to Z, > but with E and T missing, so 24 not 26 letter alphabet.   Hmm, I'm wondering if this is somehow related to old crypto gear?   Jon

N_Cook <diverse@tcp.co.uk>: Jul 23 08:27PM +0100 On 23/07/2018 19:19, Jon Elson wrote: >> but with E and T missing, so 24 not 26 letter alphabet.   > Hmm, I'm wondering if this is somehow related to old crypto gear?   > Jon   That crosssed my mind because I went to a talk by Simon Scharma on the Enigma machine and I run science talks, where we had an owner and expert on these things, transcript of that talk here http://www.diverse.4mg.com/scicaf2012b.htm Somewhere along the way there was mention about a lack of letter Q or something like that in the German alphabet and so the keyboard had no Q or J or whatever the letter was. Also , in passing ,a genuine German Enigma machine , the illumination bulbs are flattened rather than spherical , because depite the reputution of German design being so great , they cocked up and the lid would not close with the original intended bulbs, without breaking them.

KenW <kenw@nono.net>: Jul 23 12:27PM -0600 >that any brand will show the same behavior/ >Thanks, >Eric   Age and cheap brand.     KenW

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