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#1
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
I can't believe it's so hard to find simple parts any more. Radio Shack
seems to have become worthless in the past few years. I installed a 120V neon indicator (pilot) lamp in some of my wall switches to tell me when an outside or otherwise unseen light is on. Seems like these little neon lights get dimmer over time until they are worthless. I've heard of 120V LED pilot lights. Are they much better than the neon ones? I'm looking for a known mail order supplier who will sell me only two or three at a reasonable price and not kill me on shipping. I'm surprised I didn't see them on the Hosfelt Electronics site. I've found them on some other sites but the prices seemed kind of high to me. I thought someone here would know of some good suppliers. I'd just buy a switch with a pilot light, but some of the places I installed them are double wall switches (two in a group) and are of the fancy rectangle switch kind instead of the older toggle switch. I just drilled a hole in the switch place between the two switches for the lamp. Any help or comments or alternate ideas would be appreciated. Thanks! Ted |
#2
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
Hi Ted
May I suggest several things. 1. those square switches can probably b had with built in indicators that are part of the rocker. 2. Both neon and LEDs require a ballast resister which with out they will meet their demise before the intended time. Also since a LED is as its name would imply, a diode and therefore conducts only on one half of a cycle unless you wish to use a bridge rectifier with it. 3. Also I would advise that you should be certain that the combined devices meet applicable safety regulations. 3. A good place to find all sorts of electronic parts would be Allied Electronics which was or is part of Radio Shack. If you look around on their web site you should find a page with menu that allows you to order their phone book size catalog, which I received for free about 6 months ago. Cheers.. Al "Ted Swirsky" wrote in message newsp.s76g2bukrwebfy@oemcomputer... I can't believe it's so hard to find simple parts any more. Radio Shack seems to have become worthless in the past few years. I installed a 120V neon indicator (pilot) lamp in some of my wall switches to tell me when an outside or otherwise unseen light is on. Seems like these little neon lights get dimmer over time until they are worthless. I've heard of 120V LED pilot lights. Are they much better than the neon ones? I'm looking for a known mail order supplier who will sell me only two or three at a reasonable price and not kill me on shipping. I'm surprised I didn't see them on the Hosfelt Electronics site. I've found them on some other sites but the prices seemed kind of high to me. I thought someone here would know of some good suppliers. I'd just buy a switch with a pilot light, but some of the places I installed them are double wall switches (two in a group) and are of the fancy rectangle switch kind instead of the older toggle switch. I just drilled a hole in the switch place between the two switches for the lamp. Any help or comments or alternate ideas would be appreciated. Thanks! Ted |
#3
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
On Wed, 19 Apr 2006 08:03:06 -0400, "ALBERT C. GOOD JR."
wrote: .... 2. Both neon and LEDs require a ballast resister which with out they will meet their demise before the intended time. Also since a LED is as its name would imply, a diode and therefore conducts only on one half of a cycle unless you wish to use a bridge rectifier with it. --- Not necessary, just connect a diode across it in anti-parallel. However, using a 20mA LED at 20mA would require the current limiting resistor to dissipate about 2-1/2 watts, not a good idea. Using a high-efficience 2mA LED would require the resitor to dissipate about a quarter of a watt, so a 62,000 ohm half-watt resistor would do it. -- John Fields Professional Circuit Designer |
#4
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
"Ted Swirsky" schreef in bericht newsp.s76g2bukrwebfy@oemcomputer... I can't believe it's so hard to find simple parts any more. Radio Shack seems to have become worthless in the past few years. I installed a 120V neon indicator (pilot) lamp in some of my wall switches to tell me when an outside or otherwise unseen light is on. Seems like these little neon lights get dimmer over time until they are worthless. I've heard of 120V LED pilot lights. Are they much better than the neon ones? I'm looking for a known mail order supplier who will sell me only two or three at a reasonable price and not kill me on shipping. I'm surprised I didn't see them on the Hosfelt Electronics site. I've found them on some other sites but the prices seemed kind of high to me. I thought someone here would know of some good suppliers. I'd just buy a switch with a pilot light, but some of the places I installed them are double wall switches (two in a group) and are of the fancy rectangle switch kind instead of the older toggle switch. I just drilled a hole in the switch place between the two switches for the lamp. Any help or comments or alternate ideas would be appreciated. Thanks! Ted Ted, IMHO the simple neon bulbs are still the easiest indicators. They will last long, most of the times longer then the equipment they are build in. That's where I get most of them from. Neon bulbs are made for various currents. They will give more light and live shorter when you feed them more then the nominal current. Less current gives less light but a longer lasting indicator. Neon bulbs are for sale by Farnell for instance. But, of course, you'll have to pay much more for handling and shipping then the price of the bulbs. If you can get the right LEDs cheaper they are a good alternative. But LEDs require verry low voltage and relative high currents. So a "standard" 20mA LED will consume almost 2,5W to be dissipated in the serial resistor. I ever made a circuit to use such a LED even at 230V but it takes quite some space (and money). So to keep things simple, you'll have to use high efficiency LEDs that require 2mA or even less. To make it really efficient you'll have to add a bridge rectifier but four small general purpose diodes will do. Sometimes someone advises to use one antiparallel diode but then you throw away half of the light you can have for the same money. petrus bitbyter |
#5
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
Both neons and LEDs have the same problem - series ballast resistors. These
high value resistors with high voltage drop always drift high over time, reducing the current and leaving the light dim. The solution? If you can hack the fitting apart, replace the resistor. Pretty simple job really. I've never found the neon or LED to have actually dropped in efficiency. It's always the resistor. "petrus bitbyter" wrote in message ll.nl... "Ted Swirsky" schreef in bericht newsp.s76g2bukrwebfy@oemcomputer... I can't believe it's so hard to find simple parts any more. Radio Shack seems to have become worthless in the past few years. I installed a 120V neon indicator (pilot) lamp in some of my wall switches to tell me when an outside or otherwise unseen light is on. Seems like these little neon lights get dimmer over time until they are worthless. I've heard of 120V LED pilot lights. Are they much better than the neon ones? I'm looking for a known mail order supplier who will sell me only two or three at a reasonable price and not kill me on shipping. I'm surprised I didn't see them on the Hosfelt Electronics site. I've found them on some other sites but the prices seemed kind of high to me. I thought someone here would know of some good suppliers. I'd just buy a switch with a pilot light, but some of the places I installed them are double wall switches (two in a group) and are of the fancy rectangle switch kind instead of the older toggle switch. I just drilled a hole in the switch place between the two switches for the lamp. Any help or comments or alternate ideas would be appreciated. Thanks! Ted Ted, IMHO the simple neon bulbs are still the easiest indicators. They will last long, most of the times longer then the equipment they are build in. That's where I get most of them from. Neon bulbs are made for various currents. They will give more light and live shorter when you feed them more then the nominal current. Less current gives less light but a longer lasting indicator. Neon bulbs are for sale by Farnell for instance. But, of course, you'll have to pay much more for handling and shipping then the price of the bulbs. If you can get the right LEDs cheaper they are a good alternative. But LEDs require verry low voltage and relative high currents. So a "standard" 20mA LED will consume almost 2,5W to be dissipated in the serial resistor. I ever made a circuit to use such a LED even at 230V but it takes quite some space (and money). So to keep things simple, you'll have to use high efficiency LEDs that require 2mA or even less. To make it really efficient you'll have to add a bridge rectifier but four small general purpose diodes will do. Sometimes someone advises to use one antiparallel diode but then you throw away half of the light you can have for the same money. petrus bitbyter |
#6
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
On Thu, 20 Apr 2006 01:40:29 +0200, "petrus bitbyter"
wrote: If you can get the right LEDs cheaper they are a good alternative. But LEDs require verry low voltage and relative high currents. So a "standard" 20mA LED will consume almost 2,5W to be dissipated in the serial resistor. I ever made a circuit to use such a LED even at 230V but it takes quite some space (and money). So to keep things simple, you'll have to use high efficiency LEDs that require 2mA or even less. To make it really efficient you'll have to add a bridge rectifier but four small general purpose diodes will do. Sometimes someone advises to use one antiparallel diode but then you throw away half of the light you can have for the same money. --- Well, almost, but the three extra diodes aren't free. :-) And then there's always: 120V----+--[LED]--+ | | +--[LED]--+ | 120V-------[62k]---+ -- John Fields Professional Circuit Designer |
#7
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
On Thu, 20 Apr 2006 09:35:07 GMT, "John"
wrote: Both neons and LEDs have the same problem - series ballast resistors. These high value resistors with high voltage drop always drift high over time, reducing the current and leaving the light dim. The solution? If you can hack the fitting apart, replace the resistor. Pretty simple job really. I've never found the neon or LED to have actually dropped in efficiency. It's always the resistor. --- I find that hard to believe. The part about the resistor(s) drifting high, that is. Do you have any hard data to support that hypothesis? -- John Fields Professional Circuit Designer |
#8
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
John - many thanks for your post! I have a power supply with a neon
that is so dim I can hardly see it in daylight. I had assumed the neon was faulty. Changing the resistor will be much easier (provided I can read its value). But I guess I could just experiment starting with high values until it glows ok! At least once I get it apart, I can replace the neon if needed. To Ted - sorry I am in NZ. I have a stack of neons of which I would gladly send you some - but I guess postage might be a problem. Hopefully you have managed to locate some now. Eric Sears ZL2BMI. |
#9
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
John wrote:
Both neons and LEDs have the same problem - series ballast resistors. These high value resistors with high voltage drop always drift high over time, reducing the current and leaving the light dim. The solution? If you can hack the fitting apart, replace the resistor. Pretty simple job really. I've never found the neon or LED to have actually dropped in efficiency. It's always the resistor. I have never had to replace the resistor connected to a neon, unless it was broken. I have replace hundreds of bad neons. The metal to glass seals are not perfect, and the neon and other gas slowly escapes, causing the lamp to fail. Think about it. A lot of people make their living making replacement neon tubes for signs that are flickering. -- Service to my country? Been there, Done that, and I've got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida |
#10
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
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#11
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
On Thu, 20 Apr 2006 15:30:36 -0500, John Fields
wrote: On Thu, 20 Apr 2006 11:14:59 GMT, (Eric Sears) wrote: John - many thanks for your post! I have a power supply with a neon that is so dim I can hardly see it in daylight. I had assumed the neon was faulty. --- Your assumption was correct. Thank you also John F for your correction! While it was good to be alerted by the previous poster that I MAY have been barking up the wrong tree, the actual solution is the pull the thing apart and FIND OUT what's wrong! It can't be too difficult to fix a circuit consisting of two components (famous last words). --- Changing the resistor will be much easier (provided I can read its value). But I guess I could just experiment starting with high values until it glows ok! --- Unfortunately, by doing that you'll be needing to replace resistors with higher and higher wattage units more and more often as the neon lamp races, ever faster, to its final reward. I guess it wouldn't be a bad idea to measure the current drawn by the neon/resistor combination. What is typical? A few mA I suppose? --- To Ted - sorry I am in NZ. --- I can't imagine why, I've heard that NZ is paradise... :-) I'll rephrase that! I'm NOT sorry I'm in NZ; I'm sorry you'er not here too, where we could share both the wonderful tramping/bushwalking/scenery, and I could also share some of my years of accumulated electrical junk (er "used equipment") with you!! Thanks for all the comments. Eric Sears ZL2BMI |
#12
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Where to find a few 120V indicator indicator lights?
Eric Sears wrote:
On Thu, 20 Apr 2006 15:30:36 -0500, John Fields wrote: On Thu, 20 Apr 2006 11:14:59 GMT, (Eric Sears) wrote: John - many thanks for your post! I have a power supply with a neon that is so dim I can hardly see it in daylight. I had assumed the neon was faulty. --- Your assumption was correct. Thank you also John F for your correction! While it was good to be alerted by the previous poster that I MAY have been barking up the wrong tree, the actual solution is the pull the thing apart and FIND OUT what's wrong! It can't be too difficult to fix a circuit consisting of two components (famous last words). --- Changing the resistor will be much easier (provided I can read its value). But I guess I could just experiment starting with high values until it glows ok! --- Unfortunately, by doing that you'll be needing to replace resistors with higher and higher wattage units more and more often as the neon lamp races, ever faster, to its final reward. I guess it wouldn't be a bad idea to measure the current drawn by the neon/resistor combination. What is typical? A few mA I suppose? --- To Ted - sorry I am in NZ. --- I can't imagine why, I've heard that NZ is paradise... :-) I'll rephrase that! I'm NOT sorry I'm in NZ; I'm sorry you'er not here too, where we could share both the wonderful tramping/bushwalking/scenery, and I could also share some of my years of accumulated electrical junk (er "used equipment") with you!! Thanks for all the comments. Eric Sears ZL2BMI How are you going to maesure it? The neon has a minimum firing volatge and only conducts for part of each half cycle. -- Service to my country? Been there, Done that, and I've got my DD214 to prove it. Member of DAV #85. Michael A. Terrell Central Florida |
#13
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
On Tue, 18 Apr 2006 00:30:14 GMT, "Ted Swirsky"
wrote: I can't believe it's so hard to find simple parts any more. Radio Shack seems to have become worthless in the past few years. I installed a 120V neon indicator (pilot) lamp in some of my wall switches to tell me when an outside or otherwise unseen light is on. Seems like these little neon lights get dimmer over time until they are worthless. I've heard of 120V LED pilot lights. Are they much better than the neon ones? I'm looking for a known mail order supplier who will sell me only two or three at a reasonable price and not kill me on shipping. I'm surprised I didn't see them on the Hosfelt Electronics site. I've found them on some other sites but the prices seemed kind of high to me. I thought someone here would know of some good suppliers. I'd just buy a switch with a pilot light, but some of the places I installed them are double wall switches (two in a group) and are of the fancy rectangle switch kind instead of the older toggle switch. I just drilled a hole in the switch place between the two switches for the lamp. Any help or comments or alternate ideas would be appreciated. Thanks! Neon lights are hard to beat for simplicity and light output. LEDs are practical in that application. I have a LED night light it stays on 24/7 and I replace the three leds about every four years because they get dim Don't use a resistor to drop the voltage if you use a LED - use a capacitor. costs more, but dramatically lowers the heat and power consumed. I use a bridge rectifier for the three leds and a .47 UF 200 VAC cap to limit the current into the rectifier. (at 60 cycles and 120 volts - 240 volts would be half that value) Use a 100 ohm 1/4 W resistor in series with the cap. Ideally it "should" be a flameproof resistor but the standard carbon film ones open without burning if the cap shorts. (which I managed to do while assembling my light - didn't even singe the paint on the resistor - tiny flash of light - and shorted all three leds) The resistor limits the inrush current to the led and works as a fuse. You could ditch the rectifier and use two leds in a back to back configuration to work on each half cycle of the sine wave. One LED and a diode in series with the LED or across the LED so it is forward biased when the LED is reverse biased. If you use half wave power you can double the current for the same light output. Calculate the capacitive reactance to determine the cap size needed for the voltage and frequency of your mains and current you intend to run. -- ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
#14
Posted to sci.electronics,alt.electronics
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Where to find a few 120V indicator indicator lights?
"default" schreef in bericht ... On Tue, 18 Apr 2006 00:30:14 GMT, "Ted Swirsky" wrote: I can't believe it's so hard to find simple parts any more. Radio Shack seems to have become worthless in the past few years. I installed a 120V neon indicator (pilot) lamp in some of my wall switches to tell me when an outside or otherwise unseen light is on. Seems like these little neon lights get dimmer over time until they are worthless. I've heard of 120V LED pilot lights. Are they much better than the neon ones? I'm looking for a known mail order supplier who will sell me only two or three at a reasonable price and not kill me on shipping. I'm surprised I didn't see them on the Hosfelt Electronics site. I've found them on some other sites but the prices seemed kind of high to me. I thought someone here would know of some good suppliers. I'd just buy a switch with a pilot light, but some of the places I installed them are double wall switches (two in a group) and are of the fancy rectangle switch kind instead of the older toggle switch. I just drilled a hole in the switch place between the two switches for the lamp. Any help or comments or alternate ideas would be appreciated. Thanks! Neon lights are hard to beat for simplicity and light output. LEDs are practical in that application. I have a LED night light it stays on 24/7 and I replace the three leds about every four years because they get dim Don't use a resistor to drop the voltage if you use a LED - use a capacitor. costs more, but dramatically lowers the heat and power consumed. I use a bridge rectifier for the three leds and a .47 UF 200 VAC cap to limit the current into the rectifier. (at 60 cycles and 120 volts - 240 volts would be half that value) Use a 100 ohm 1/4 W resistor in series with the cap. Ideally it "should" be a flameproof resistor but the standard carbon film ones open without burning if the cap shorts. (which I managed to do while assembling my light - didn't even singe the paint on the resistor - tiny flash of light - and shorted all three leds) The resistor limits the inrush current to the led and works as a fuse. You could ditch the rectifier and use two leds in a back to back configuration to work on each half cycle of the sine wave. One LED and a diode in series with the LED or across the LED so it is forward biased when the LED is reverse biased. If you use half wave power you can double the current for the same light output. Calculate the capacitive reactance to determine the cap size needed for the voltage and frequency of your mains and current you intend to run. -- ----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- A series capacitor is a good idea if price and dimensions will give no problem. It's even better if heath is (a problem). You will save energy as you have less dissipation. I only consider the 100 Ohm resistor pretty low to suppress the inrush current. It may do for a 24/7 nightlight but in equipment that has to be turned off and on several times a day, the LEDs may degrade or blow pretty fast. After all the worst case peak current will be over 1.5A. To stay on the safe side, this peak current should not exceed the LEDs peak current. The latter depends on the LED you use, so you'll need its datasheet. petrus bitbyter. |
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