Does anyone have experience with these devices? Looks like a clever and inexpensive source of emergency lighting if the power goes out, but the phones are still working.

http://www.8starshop.com/en/8-led-desk-table-reading-lamp-light-telephone-powered.html

I apologize if this has already been posted here.

Got me to thinking. Is the power from the phone jack free
(other than the monthly rate you already pay)?

Lights like this get posted from time to time. I would not recommend them, not because they are useless, but because the phone system is not meant to power appliances. If too many people use products like this, then the real purpose of the telephone system--to make calls--could be impaired.

The signaling on the POTS (plain old telephone system) relies on changes in line voltage, which is why plugging devices like this into your phone jack is not a good idea.

Interesting link...

Free electrity from phone jack

It's been forever, but I remember the line have super low current; like .02 amps or some such. So not sure what you could actually run with it.

I previously worked for S.W.B.T. now A.T.&T. (again).
Standard line voltage is -48 VDC @ approx. .25 Milliamperes. YES .25
Ringing Line voltage is approx. 90 VAC.

-----Quote----- I would not recommend them, not because they are useless, but because the phone system is not meant to power appliances. If too many people use products like this, then the real purpose of the telephone system--to make calls--could be impaired. --

Remember each POTS line is on its own cable pair. The short created by the light will "break dial tone" and show that line as "busy" assuming anyone remembers the busy signal. (long gone due to Voice Mail for most).

Too many of these lights will eventually either cause the lightening protectors (read fuse) to blow and kill all power to the residence on that pair or worse. Worse being that the small (standard = 22ga) inside wire to overheat. You won't need the fire steel then, because the ember will be to you soon via the fire in attic/walls.

Save some trouble, use the money intended to buy the "phone lights" and buy more batteries for flashlights you have.

Wow, only 0.25 mA? That's tiny. OK, learned something new. So these lights not only can screw with the line voltage, but the phone line is normally only intended to carry a very, very small current.

Remember that one of the standard post-earthquake practices, besides checking for injuries, fires, and gas leaks, is to go around and make sure that any telephone handsets that got knocked off the hook are put back. All those handsets being off the hook can overload the phone system, signaling-wise. Imagine if there's a blackout and everyone suddenly plugs these LED lights into their phone jacks at the same time trying to draw power at the same time. From what Desperado just posted, that could cause a whole 'nother set of problems.

the transformers are not to up low amperage they are to drop the voltage down to close to where an LED can use them. LED's run at 2v and below and don't require much current at all. If your wanting to switch to those in a small apartment then I would run some low voltage wiring around and use one high efficient switching power supply to drop the voltage down. Or switch to battery powered lights and use a good charger like a maha and some good low self discharge batteries.

IZZY check PM