How can you make a LED light run off a phone jack for emergencies?
2007-09-02 12:58:50 · 4 answers · asked by David H 1 in Consumer Electronics ➔ Land Phones
What you describe would be like a nightlight or small light plugged into the phone jack for power. The phone jack does supply power so your phone can light up and ring. I don't see why it couldn't be done.
I did a search on the internet, and could find no companies offering such a thing. Maybe there's an invention and new market to be developed here.
2007-09-02 18:55:22 · answer #1 · answered by Uncle Pennybags 7 · 0⤊ 0⤋
Phone Jack Light
2016-12-18 09:44:14 · answer #2 · answered by ? 4 · 0⤊ 0⤋
An l.e.d. is a contemporary operated device, many times rated at 20mA maximum. At that contemporary the forward voltage would be a pair of million.8 to two volts for a crimson l.e.d. and another colorations (seem them up on Google). different colorations strengthen 3 or 4V in the time of them. For useful operation the audio output could have the skill to grant a minimum of 10mA or the l.e.d. would be slightly faint. As has been stated, attempt it. despite the fact that the l.e.d. could have a contemporary proscribing resistor in sequence with it, you may come across a serendipitous placing of the source's quantity administration which does no longer wreck your le.d.s.
2016-12-31 10:22:56 · answer #3 · answered by ? 3 · 0⤊ 0⤋
heres a bunch of stuff developed to work off of telephone power:
http://www.sandman.com/telco.html
but if all you need is a little LED light, then something like this is proballay more what you are looking for
http://peaceful.manufacturer.globalsources.com/si/6008800807581/pdtl/Circuit-breaker/1001387237/Telephone-Line-Tester.htm
these can be purchaced at almost any electrical supply house, alarm supply store, or home depot/lowes...
2007-09-04 16:13:09 · answer #4 · answered by joe r 7 · 0⤊ 0⤋