Emergency Power From Telephone Lines





Introduction: Emergency Power From Telephone Lines

About: Hello, I am 17 year old innovator living in India. My interest lies in Electronics. Surf through my creations and enjoy!!!!1

Do you Know that you can lookout for emergency power from your telephone Lines? Yes it's True that you can do it and in a very few simple steps. In electricity cut off also, this system works 24/7. You can take off power from telephone lines whenever you want. After all, who doesn't want Free Electricity?

I will tell you some applications of the telephone line power and will discuss about its specifications. We will do all this with the help of Telephone Line Cable RJ11 CABLE. This is easily available at any place and also widely used.

Using the power from telephone lines is extremely easy and anyone can do it. However Telephone Department do not mind the electricity usage.

Go on Reading and I am Sure you would find it interesting.


Step 1: Materials Required

1. Telephone Line Cable RJ11 CABLE. (Digikey)

2. LED (Sparkfun)

3. 5v DC-DC Boost Converter (Digikey)

4. 1.5v Rechargeable Cell (DigiKey)

5. 1.5v Cell Holder (Optional)


1. Wire Cutting and stripping Tool

Step 2: RJ 11 Cable

RJ11 Cable is also known as Telephone Line Cable and it is easily available at any place. You can find one connected to your Landline. By this cable, your phone can remain active.

This cable has two wires inside carrying some voltage and current. With no cells also your phone can live with the power of Telephone Line.

Step 3: Splitting

Splitting is the most necessary and somewhat difficult job to do so. First of all, cut out one of the connector from the RJ 11 Cable.

Then take out the outer covering of the wire. The two wires you can now see are extremely delicate. These are the wires that carries voltage and current and it is difficult to take out its copper part of inside.

Now, expose the copper part and your cable is ready to power.

Step 4: Voltage

After getting the cable ready connect the split wires to the terminals of the multi meter and check the voltage.

You will notice that the display shows around 45 volts. The voltage are really much in amount.

Step 5: Current

Now, put the terminal of the multi meter up and tune it to get the reading of the current.

You will get current between 0.02A and 0.03A which is very low in amount.

Step 6: Some Mathwork

As we have seen our voltage and current. We have assumed to have more power but as in this case amperes are less so voltage seems to be little. For the accuracy we have to check the power. However, getting voltage is much easier than to get power.

Here the voltage is 45 Volts and current is between 0.02A and 0.03 A. So, let us take it as 0.025 Ampere. Now, the Power we get is:

Power = Voltage x Ampere

= 45 x 0.025

= 1.125 Watts

Step 7: Lighting LED

As we have seen, we got 1.125 Watts which is enough to light LED. So, lets light LED.

In order to light LED, just connect the LED to the telephone Line Cable's Wires that we have split earlier.

You can connect the LED in any polarity. It really doesn't matter in which polarity you are connecting LED. It will light up brightly.

Step 8: Charging a Cell

Charging a cell from telephone line power can help you do many things. Just attach the split RJ11 Cable to the cell holder or directly to the cell.

It can take 4-5-6 hours to charge completely to 1.2v and 0.5 A.

Step 9: Mobile Charging

Mobile Charging is the main issue for everyone. It is difficult to directly charge the cell from the telephone line. However, it is not impossible. But the simple trick is to owe a DC-DC Boost Converter. In input you should connect your charged cell from the previous step.

Image here shows a DC-DC Boost Converter.

You can now charge the mobile by simply connecting Data Cable from Converter to mobile phone.

You can also charge it in your simple way and also this is not the only way.

Step 10: Thank You

I hope you found this information useful.

Thanks for Stopping By...

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    The author fails to account for voltage drop under load in the power calculation. I.e., you do NOT get 45V at 25mA. You'd be lucky to see a tenth of a watt at best.

    I agree with Josh Blackburn comments. The author should not be offended but be grateful for such good comments and learn from them. Keep tinkering and expanding your mind.

    Theft (in 99.9% of countries) now gets featured !!!!

    This is not 'free' electricity, it is stolen electricity.

    Also if you put devices on there it will reduce the amount of time that the phones can stay working for the case of an emergency during a blackout.

    1 reply

    Not legal even in India. But electricity theft is widespread there, ~80% of generated is stolen!

    Using the power from telephone lines is extremely easy and anyone can do
    it. However Telephone Department do not mind the electricity usage.

    This may be quite true in your locale, however as a maker you should be aware that other parts of the world have different regulations and concerns. I suggest a simple forward such as:

    "While this design is approved for use in my town/ village, your local code and utilities terms of use may prohibit it, so do check first before implementing such a device."

    Now you're off the hook as far as liability goes, however there may still be technical discussions and disagreements about your design, and that is something else entirely, do not take offense, it is not- or it should not be- considered a personal attack.

    This is unsafe and irresponsible. Anyone that reads this should not be messing with phone line power.

    100% illegal in the United States. AT the very least, you will get told to remove your device immediately when you get caught. Next step up will be a charge of "Theft of Services" which will cost you a bundle just to defend yourself. And finally, ou could lose your ability to ever have a land line phone ever in your life. Which may not be a big thing anymore but...

    there are quite a few things legal in India that are illegal in the USA, UK, AU, France, et cetera

    1 reply

    I don't know where you live, but while it may be legal there, it is not legal where I live. I would suggest telling people to check their area for legality.

    As for the risk of LED burn out, yes, there is a risk. Even going off of your measurements, which, I might add, are not the maximum possible levels, there is 45v at 0.02A, which gives 0.9W. The LED you show, along with most standard LEDs, is rated for 0.06W, which means you could potentially overpower the LEd by 15 times.

    Please, just do the research and do the math and understand the risks involved here. After that, if you want to make it, go ahead, but make sure to tell other people the risks involved. It is very irresponsible and honestly immature to post potentially dangerous and illegal ideas like this without sharing the risks as well.

    Even as spec'ed this isn't safe. The DC-DC converter is only rated for 12VDC, and you've measured it at 45VDC!

    I'd like to see your board when the 90v ac ringing shows up.

    This may be legal in India but is certainly illegal in the UK. I agree with the other comments regarding the dangers.

    I agree with the other poster this is terrible advice and should not be on this site. This is theft, its not any different than using an inductor coil to steal power from overhead electricity.

    This is NOT a complete or even safe tutorial. Please do some research before messing with power systems like this. A few points I'd like to mention without going into too much detail.
    1. This is illegal in many, if not most, countries. Landline phone service is considered an emergency service, hence it does not go out when the power is out. Thus it is generally illegal to tamper with it, as you have shown here.
    2. There is both AC and DC current at different times. When unloaded, the voltage is around 48v DC. When in use (loaded) it is around 3-9v DC. When receiving a call, it is up to 90v AC. This means that any device you connect MUST have a rectifier and MUST be able to use between 3 and 120 volts, or it will not be safe.
    3. Because there is such a range of voltage, and there is AC, batteries should absolutely NOT be charged with this. Additionally, LEDs and other lights should not be used either, as they can blow out and potentially be dangerous.
    However, this is somewhat a mute point, as this is generally illegal anyway. So please, do some research, make sure this is legal where you are and make sure you understand the mechanics of the system.