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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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