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Re: A noisy pilot light !
开云体育Ahhh, thanks Dale. ?I see the bayonet and that you can get ?Warm 2700K bulbs, but I did not see where it said about an internal current limiting resistor, and maybe a diode? I will have to look again. That solves a good part of my question. So do you leave them running as a parallel set,? or change them to run in series? Don VA3DRL ? From: [email protected] [mailto:[email protected]] On Behalf Of Dale Parfitt
Sent: Saturday, October 1, 2022 5:32 PM To: [email protected] Subject: Re: [HallicraftersRadios] A noisy pilot light ! ? These are a single LED with a? current limiting resistor, built into a Bayonet socket: ? Dale W4OP ? From: [email protected] [mailto:[email protected]] On Behalf Of don Root ? I keep wondering out of ignorance,? when we say “LED” do we the just one bare-bones LED device, or do we mean? a LED with some power conditioning electronics built-in as well ?,, perhaps using HF switching devices? Don VALDRL? ?again ? From: [email protected] [mailto:[email protected]] On Behalf Of Randy.AB9GO ? I have LED replacements in my Drake 2B and they are RF quiet.?? ? _========trimmed again_,_ ? |
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Re: The 3 -Amp fuse that almost ate a city.
How about this one.
True Story, this was in a 50's or 60's Popular Electronics magazine. A woman calls a TV repair guy with a problem with their TV, the repairman shows up, fixing the TV (bad tube) and goes home. Late that night, the woman call again and this time the problem is the TV will not shut off, because the dial light is still on. On the phone, the repair guy tells the woman to do various things and finally tells her to pull the plug. She told him the light is still on. This he had to see, jumps in his car goes to her house and sure enough, the dial light is on with the TV plug pulled. He pulls the back off the TV and finds out he left his penlight perched on the channel selector drum. K2WH |
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Re: A noisy pilot light !
开云体育Gary, I am not informed about this stuff? ?,so I just looked up a bit more, and it seems that there are many variations of circuitry? and some use PWM and must be noisy, but yours is simple, with warm white LED ?so perhaps makes it? look normal . Perhaps I have been turned-off? by pictures of older ones that were to me a horrible eye-burning blue. I expect that the cooler LEDs will save some dial scales from further deterioration… so would be worth the change to a warm white. Again out of ignorance, I wonder how the alteration is made.. the usual original bulb is held by a bayonet socket.? Can you stuff a LED into it ? my guess is that you would want LEDs to be in series so the usual mounting of a bayonet won’t work so well because they are “grounded” to the chassis. Don ?VA3DRL ? From: [email protected] [mailto:[email protected]] On Behalf Of wb6ogd
Sent: Saturday, October 1, 2022 5:32 PM To: [email protected]; don Root Subject: Re: [HallicraftersRadios] A noisy pilot light ! ? Don, I build my own.? They look so much better than old bulbs and make the radio unbelievably cooler, usually up front by the mechanics and the oscillator, makes it more stable and makes it last longer. I use a diode(LEDs don't run on AC for long), a resistor, and the LED (warm white!). Nothing to make noise. 73, Gary ????????????WB6OGD ?
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Re: A noisy pilot light !
Back several years before my day there were issues with the old Edison cage type filament lamps. It was noticed that it was either around channel 3 or 4 the lamps or oscillating and causing interference on early television sets. The fix was just to replace the bulb.? I read about this in an old 1940s or '50s TV repair magazine and I asked my uncle about it who was in TV repair. He said it was a thing.? So they're making that style lamp again for nostalgia reasons. The first time I saw them I wondered about the oscillation problem. I guess they never fixed it.??
randy.ab9go@... |
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Re: The 3 -Amp fuse that almost ate a city.
开云体育Sorry guys.. another story ?slightly off topic ? Back in 1990’s? they were removing a tree next to a power line ?2 doors away and at the moment in question they had the boom truck bucket and cutter guy right beside the power pole and wires.? The situation had gathered and audience of local? onlookers, and suddenly all the lights went out, the rest of the street came over? pointing fingers? etc, .? The tree cutters were fine, but we all labeled them as guilty. ?They must have had an earlier cell phone,? and said the power was out everywhere: ?most of southern Ontario and maybe down south. It took a while for us to believe them, but some radio stations were still running and the news came thru. So it wasn’t them. There was a major Outage. ? Fast forward a few years, when I had 6 Ash trees infected with the Ash Borer, so they had to go. One of the trees at the front was what I call a Vee tree and the big? trunk was very tilted towards the street.? ?I came back from lunch with a friend? to find another gathering .. power trucks down the street and at my place and people standing around, and that big hunk of ,30-40 feet of tree had landed on the ground and into the street, taking the street power lines down and ripping lines right off some houses. Luckily I had hired a contractor, not a friend.?? It was not long before every tree cutter in town was taking a tour around the block ?to see what they had done. The laws of physics prevailed: that tree was destined to go over the power lines and onto the ?road, if it was cut in such ?a long piece. Sometimes stuff does not fail? but peoples’ brains fail. ? Don VA3DRL
? From: [email protected] [mailto:[email protected]] On Behalf Of William Barrett, KW1B via groups.io
Sent: Saturday, October 1, 2022 1:21 PM To: [email protected] Subject: [HallicraftersRadios] The 3 -Amp fuse that almost ate a city. ? I'll trade this one in return: ? I was working on a minor problem with an "NF-105" receiver by Singer-Metrics.? I had taken the line?fuse out for safety: cartridge style, bayonet rear panel type, 3-Amp.? Common. ? I finished the tweak and put the fuse back in.? The instant I did, all the lights in the (RF shielded enclosure/room) went out!? As an instant nerve reaction, I pulled the fuse back out. ? The lights instantly came back on.? This geatly puzzled me, so after a beat, and a dumb-ass frown, I stuck it back in.? BANG!? The lights went out! ? Instinctively, I jerked it right out again -- and the lights and all the other things in the room -- mostly other instruments or test gear -- all popped back to life. ? So, being a stubborn and determined if puzzled worker, and realizing This Was All Quite Impossible, I stuck it back in. ? And BANG! The lights and everything else?went out instantly!! This time, though, as I retracted, the lights stayed out. ? I went out to the production floor and found the Plant Manager, a very powerful title in Real American Industry.? All the big machines were spinning down, the emergency lights had come on, and there was lots of excited hollering and running feet. ? General Big-Ass Huge Power Failure.? Metal band saws had stalled and seized up in the workpiece, lathes were spinng down or jammed, total chaos.? My guilt was very strong. ? I found the plant manager, and as I was apologizing to his VERY distracted self, he said, "Whattya want Kidd?? Can't you see the power's off? There's a big thunderstorm outside, and a branch fell over the power lines!!? Get OUTTA my face !!!!? WhatEVER you want, we'll fix it later!!!!"? and he re-joined all the running and hollering people. ? Turns out...?? Some utility pole transformers have a "Try-Three-Times And-Quit" sorta restore switch.? And it had tried three times and blown open till the fault wold be removed by the linemen, and re-set. ? By purest of coincidence, my fuse stickings had all quite accidentally and coincidentally PERFECTLY synched up with the 3X & Die protector out in the street. ? I thought I had somehow (impossibly) blown the whole plant with my little 3-Amp fuse. ? ??? 73 KW1B ===? trimmed |
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Re: A noisy pilot light !
开云体育I keep wondering out of ignorance,? when we say “LED” do we the just one bare-bones LED device, or do we mean? a LED with some power conditioning electronics built-in as well ?,, perhaps using HF switching devices? Don VALDRL? ?again ? From: [email protected] [mailto:[email protected]] On Behalf Of Randy.AB9GO
Sent: Saturday, October 1, 2022 11:51 AM To: [email protected] Subject: Re: [HallicraftersRadios] A noisy pilot light ! ? I have LED replacements in my Drake 2B and they are RF quiet.?? ? _========trimmed again_,_
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Re: A noisy pilot light !
开云体育That’s Interesting Mike;? now? why did it trip?, and what would happen if like most radios, there was no power switch/ breaker? ?to trip?. I don’t know the RT-524 at all ,? but we wonder if the? “breaker” had been set higher or there was breaker-function ?what would happen ? ?? One might ask if the dial lamps circuit should be separately fused.??? One wonders if the breaker was not there ,would the light blow open? Or stay shorted and melt the transformer ,,and then maybe blow the fuse on? the main? panel to a bunch of stuff? ‘ ? in somewhat similar situations, I recall many room lighting bulbs “blowing out”, and usually they went like a flash-bulb.. they didn’t just go dark, so it seems that something likely shorted and got very hot causing a burst of light and blowing the guts apart, before going open, and never blowing the 15 amp protection at the main panel . ? My vintage [1950’s] Tektronix 555 scope had one of the beams not working when I bought it, and I eventually found a fuse 1/8 amp? that was ?soldered-in ?and had opened. I replaced it and Voila. ? Just in case you guys are wondering about these questions, I spent some time in ?safety design in Nuclear stations, where consequences of any failure need to be evaluated so i ask lots of questions. ?? Don VA3DRL??????????????? ????????????????????????????????????????????????????????????????????????????????????????????????? ? From: [email protected] [mailto:[email protected]] On Behalf Of Mike
Sent: Friday, September 30, 2022 11:31 PM To: [email protected] Subject: Re: [HallicraftersRadios] A noisy pilot light ! ? Joe et al. ? Another interesting tid bit of information regarding those incandescent light bulbs. ?I will make this “short” and interesting. ? Many years ago back when I was a Tech in the service, there was an RT-524 that got passed around the shop as each Tech who tried to work on it was stumped.? The symptom was as soon as you turned it on it would trip its power switch, so there was a sort somewhere, but no could find it.? By the time it landed on my Test bench it had been through 4 other Techs all claiming it was a candidate for either Cannibalization or Depo. I worked on it for a day, got frustrated cause how could I not find a simple short.? So I put it off to the side for a couple of days in favor of some other jobs that were more pressing.? One night I woke up with an idea, actually it was a memory of something that happened to my father (Retired IBM FSE) while he was troubleshooting a Main Frame that was acting “funny” as he put it.? So that morning I put that radio back on my bench, pulled a brand new Dial Lamp from parts and replaced the old one.? As soon as I turned the power on, the radio came up just fine, passed all the receive and transmit tests.? Sure enough, that light bulb had a dead short.? When asked by the other techs what was the root cause, I told them sometimes you just have to think outside of the box and look where you least expect it.? That was one of the many lessons I learned from my father as I was growing up. ? Thank you, ? Mike W5CUL ? From: [email protected] <[email protected]> On Behalf Of Joe ? Hi Jim, ?=======trimmed by don this time _._,_._,_ |
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Re: Blue LED Dial Lights. (Or other colors)
开云体育The ?idea that? a “device”? is? found?? to be failed due to a short?? or failed due to an open likely depends highly on ALL the details of it’s guts, and maybe the circuit that it sits in. ? Jerry points out a case where an initial failed short event? quickly becomes a failed open situation, presumably because there is lots of available current in the supply circuit. As to Dale’s comment; ?does the 470 Ohms? just limit the peak current as the Led fails from short to open or does it allow the LED to remain shorted indefinitely, while the resistor heats up. ? Now .. I am just asking … the only thing I know about newer whitish/blueish ?LEDS? is that fuming things hurt my eyes!!!! Don VA3DRL ? From: [email protected] [mailto:[email protected]] On Behalf Of Dale Parfitt
Sent: Saturday, October 1, 2022 3:34 PM To: [email protected] Subject: Re: [HallicraftersRadios] Blue LED Dial Lights. (Or other colors) ? The bayonet LED’s have a built in? current limiting resistor- depending on voltage and color, 470 Ohms is a common value. ? Dale W4OP ? From: [email protected] [mailto:[email protected]] On Behalf Of Jerry Miel ? I assume that LED's are much like transistors and other SS devices.? Open transistors almost always started as shorted transistors but the very fine wires that connect the silicon wafers to the leads will burn out immediately with a short even with very little current available.? It is almost like a microamp fuse.? I would expect that a shorted LED would burn open long before the transformer would feel it.? Just my opinion. Jerry On 10/1/2022 9:47 AM, William Barrett, KW1B via groups.io wrote:
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Re: The 3 -Amp fuse that almost ate a city.
开云体育As a lifelong electrical engineer working in power generation and distribution, that utility device that tries 3 times to re-energize the lines, is knows as a circuit breaker reclosure. ? It actually tries to blow the fault clear.? After the third attempt, it locks out and in comes the utility guys. ? Bill K2WH From: [email protected] [mailto:[email protected]] On Behalf Of William Barrett, KW1B via groups.io
Sent: Saturday, October 01, 2022 1:21 PM To: [email protected] Subject: [HallicraftersRadios] The 3 -Amp fuse that almost ate a city. ? I'll trade this one in return: ? I was working on a minor problem with an "NF-105" receiver by Singer-Metrics.? I had taken the line?fuse out for safety: cartridge style, bayonet rear panel type, 3-Amp.? Common. ? I finished the tweak and put the fuse back in.? The instant I did, all the lights in the (RF shielded enclosure/room) went out!? As an instant nerve reaction, I pulled the fuse back out. ? The lights instantly came back on.? This geatly puzzled me, so after a beat, and a dumb-ass frown, I stuck it back in.? BANG!? The lights went out! ? Instinctively, I jerked it right out again -- and the lights and all the other things in the room -- mostly other instruments or test gear -- all popped back to life. ? So, being a stubborn and determined if puzzled worker, and realizing This Was All Quite Impossible, I stuck it back in. ? And BANG! The lights and everything else?went out instantly!! This time, though, as I retracted, the lights stayed out. ? I went out to the production floor and found the Plant Manager, a very powerful title in Real American Industry.? All the big machines were spinning down, the emergency lights had come on, and there was lots of excited hollering and running feet. ? General Big-Ass Huge Power Failure.? Metal band saws had stalled and seized up in the workpiece, lathes were spinng down or jammed, total chaos.? My guilt was very strong. ? I found the plant manager, and as I was apologizing to his VERY distracted self, he said, "Whattya want Kidd?? Can't you see the power's off? There's a big thunderstorm outside, and a branch fell over the power lines!!? Get OUTTA my face !!!!? WhatEVER you want, we'll fix it later!!!!"? and he re-joined all the running and hollering people. ? Turns out...?? Some utility pole transformers have a "Try-Three-Times And-Quit" sorta restore switch.? And it had tried three times and blown open till the fault wold be removed by the linemen, and re-set. ? By purest of coincidence, my fuse stickings had all quite accidentally and coincidentally PERFECTLY synched up with the 3X & Die protector out in the street. ? I thought I had somehow (impossibly) blown the whole plant with my little 3-Amp fuse. ? ??? 73 KW1B -- K2WH |
don Root
Bill (Group Owner)
Randy.AB9GO