Author Options:

Telephone line power help? Answered

Found a cool video from kip kay where in he tapped free energy from phoneline to power LED lamp.
I tested my phone line with a multimeter.
The readings were as follows;
Voltage - 53.8V (DC)
Amp - 61.9
So the power running through the phone is 3.33 watts approx.

So which resistors and circuits should i use to harness all 3 watts of energy from this secret source?


Thanks Sid!
I have found few American and one pakistani video which were not of much help as they all use AC Voltage in their phone line. And i am not much familiar with building circuits, so i want a circuit diagram for DC voltage for values i mentioned above. Yep, these MTNL (Mera telephone nahi lagta :p) guys are real lousy!

The line is DC on hook, AC when ringing,

Haha! "Mera telephone nahi lagta" that was a good one! :D

So, lets get to the point!.. I just tried it! (but only for a split second!) I just hooked a 2.2k resistor with an LED (3.5V, 20mA)... and it just glowed as it should have!!!

So, the thing is, that I think you could light up 5-10 LEDs easily, but only for a short period of time...
You need to exactly specify how many and which LEDs you intend to use...only then I'll be able to tell you the exact circuit...

For instance, If you were to use 5 white LEDs (3.5V, 20mA), you'd connect them in series and hook up some 1.8k resistor in series... done!...
Check this site for more help...or simply message me... :)

I tried a red led raw on the phone line. It glowed brightly. So i hooked my multimeter to check the AC voltage and viola! I got reading of 117V! Now this adds to more confusion. Are both currents flowing simultaneously?? i intend to use 5 led'??s. so whats this mystery aabout

Neah! there is no confusion!.... If you've ever tried to check the AC reading on a DC battery, you'll know it!... It gives double the reading when red is connected to positive and zero reading when connected otherwise!....

It's DC for sure!... and to connect 5 LEDs, proceed as I told you before, with LEDs and a 1.8k resistor in series.....


4 years ago


Just came back to say, it worked! (sorry for being late :)

Made a video out of it, hope it helps.

Improvised a CD holder cover and mounter 5 LED's as shown in tutorial. Again, that was just an experiment. Not intended to promote power theft.

Power cuts are next to zero these days in Mumbai, so never had chance to use it.

Thanks all.


5 years ago

Thanks. It worked. I tried the kipkays method but with 5 LED's. However ther's a problem. When an incoming call comes, the call gets automatically recieved without even picking up the phone. Whats that? The two resistors i used were 570ohms n 210ohms.

Umm... I don't know about the calls being recieved automatically..... but it could be something to do with what steveastrouk just mentioned....

anything you attach to the phone line that uses more than a few milliamperes will "trip" the line. That means the central office "switch" will see the connection as a phone 'OFF HOOK". If the off- hook occurs too long, it may disconnect your line and generate a trouble ticket for your residence. Then a phone company employee will be knocking at your door. the amount of electricity on that line is not worth playing with. get yourself a small solar cell to goof around with instead.

Thank you for advice. I thought i'll get some instructions to build one. But this is turning ouy more sort of lawyer advice. I understand the risks now plz focus on its technical part. And btw i am from India, these mtnl guys are real lousy and i am just experimenting.

First confusion is, the output is DC volts. So do i need a bridge rectifier as in kipkays video? Second, when i pick up the phone the.voltage reads as 13.4V. And when the phone rings the voltage goes to 56V. How many LED can i light with it?

Yes it is DC so no rectifier is needed. But as others are saying you won't be able to get much usable power from the line without messing with the phone system in general. If you start pulling more then the allowed 480 micro watts for any period of time it will be noticed and you could face fines.

If you want to try it for kicks then its on you. Use the voltages your getting and calculate the resistor needed to pair with your LED. You can find many LED calcs online that will help you with this. If it doesn't light check your polarities and then try a smaller resistor. But this is all on you.

Thanks. I am from India & i dont think there's any such law here. Alas, i just want to experiment with it, nothing more.
Suppose i got to use 12 LED's in series, so considering each LED needs 3V, i got 36V. So which resistors should i use? I just know basics of electronics, so i am no pro.

Yes, nice circuit, which includes the correct caveats

However, Part 68 of the US Federal Communications Commission's telecommunications regulations states that any device that connects to the phone line and is not actively communicating must present a resistance of at least 5 MΩ 

480MICROwatts of permitted load.

Loading the phone lines to extract power is likely to find you facing criminal charges in many countries. The phone authorities in most countries have equipment in place to monitor the loading on phone lines, and they will shutdown ones drawing more than the permitted load.

Don't do it.

Thanks! I am from India and i just want to try it as an experiment.