Tap into the phone company's current... if you dare
By Ryan Block 
posted October 14th 2007 7:23PM
posted October 14th 2007 7:23PM
[Thanks to everyone who sent this in, via Instructables]
posted October 14th 2007 7:23PM
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Except it is understood that a company car can only be used for work, while there is no similar understanding when you sign a lease, rental agreement, or buy a house.
This is really old. This used to be around to cut off a forced FBI trace, as the machine they used would supply extra current to keep the line open, and draining it would screw things up. That was the theory anyway.
You've read to many old phreaker txt files.
I like how the easy button is just chillin there lol
The power in the phone lines comes from a bank of batteries giving between 48 and 52 volts DC. This battery power is like the carrier frequency in radio systems where voice and data rides on top. Without the battery power the phone lines would be dead. When an incoming call is received about 115 volts AC is on the lines to ring the telephone circuitry.
Tapping into the phone line to steal power creates a load which can be detected at the Telco. Too much load shuts down the circuitry and creates a fault which someone like me would have to come and fix. So there is nothing such as free power from phone lines.
depends what you're doing. a small voltage converter and a few leds won't draw anymore than my corded phone in the bedroom that also has leds on it. in which case you wouldn't detect it, and it wouldn't blow your lines and you wouldn't need to come fix it. no harm done.
An interesting analogy comparing it to a carrier signal, and poses an argument on the legality of a leech device. Obviously if you signed a telco contract that expressly denied you the ability to leech power from the lines, it would be a breach of contract; ( but possibly not "illegal" past that ).
However, the FCC states that you cannot cause interference and must work to the best of your ability to resolve interference etc.. etc.. (see: http://www.fcc.gov/oet/info/rules/). Therefore, even if you never signed a contract; it may violate FCC rules..
If somehow draining power (however you wired it) disrupted 911 service, that could be a real issue.
I notice now that almost all of the references in the FCC rules explicitly talk about radio frequencies; so I doubt a proper judge would apply those rules to telco lines. (See: Sec. 15.17 "Susceptibility to interference." )
As far as the actual device goes,
15.23 "Home-built devices" states that any "home built device" does NOT need to be "authorized", as long as (15.23b) the engineer is "expected to employ good engineering practices to meet the specified
technical standards to the greatest extent practicable."
So, I would say that if you tried your best to design a device that drained only the power that a normal telephone would drain under all circumstances, and maybe filter it back into the power grid (make a few bucks) there is no viable reason to think that it would somehow disrupt 911 service or telco service- and therefore is not illegal.
There could be a serious problem with the new broad anti-terrorism laws however, they might try to say you were attempting to disrupt emergency services (insert headache)...
It's always amazed me that they can send power and voice/data down the same 2 wires.
it also amazes me how they can send cable internet forward and backward, and 5 video streams through one coaxial cable.
My dad who was a telstra tech here in AUS made a unit about 20 years ago which was a ringer extension which doubled as a 9v battery charger, sure it took a week to charge the battery, but it was free, the current running down the phone lines is pretty small, and as everyone has said, if you drain too much you are going to lose line quality. But realistically, the price you pay to charge a 9v battery, doesn't really weigh up to the cost of the components.
PS, with such low current, any voltage coming through the telephone lines isn't going to be dangerous. To help protect the batteries it is quite easy to separate them in a ringer unit when the phone actually rings.
o_g" Didnt think the things were that rough in the states..?!? Streets paved with gold, what happened???
No wonder the US$ is weakening..
I think you got America and Heaven mixed up there pal. Nice try...douche!
I remember a similar article in the phrack guides or some other such guide... Old stuff...
Well, Mike Sandman (who supplies all kinds of telephone related equipment) has a whole page of devices that run off of "telco power." This includes a telco powered dildo. See it here: http://www.sandman.com/telco.html
Dildo wired to the telco: a novel idea. Did somebody say 'incoming call'?
I like how these genius tools were invented by a scientist at Chernobyl, and get the 'thumbs-up' from the Director General of the Chernobyl Nuclear Power Plant. That's telling you something.
This is very, very old news. There was a company about a decade ago that used to sell all sorts of chargers and gadgets that were powered by the phone line. This is an example of one: http://www.dealextreme.com/details.dx/sku.777
If you read the testimonials of the product it says it all right there. Problems with the phone operating right, caller ID problems, light flashes when the phone rings, etc.
My favorite is that, "Well, the fun is that you don't pay for the power (or batteries) used, and since usually when electricity is out phone lines still work, it will light the dark during those emergencies".
Of course, what they don't realize is that the power through the phone line does not last forever. It is running from backups and those backups have limits. So your little light could stop the phones from working up to maybe 25 square miles. Sounds like a lot, but I know of CO's that are 15,000 feet from their customers and I personally have been 18,000 feet from the CO. There are probably many areas that are not that big, but you could affect thousands of people at once.
I like how the easy button is just sitting there.
Old news. And illegal too. Not sure why this is worth posting on a 'gadget' blog too.
I'm sure that you would get arrested for a few things. Especially if it somehow knocked out the phone system for the entire neighborhood. Like interfering with emergency communications.
Isn't it great how superior technologies are ignored by emergency people?
If I have a GPS unit, I could send them pretty good location data over VoIP. Do they ask for that? No. They ignore VoIP as a legit form of communication. Kind of like all those 'designed for Windows' stickers on PC's. Simply unfortunate. ...Gutsy's gonna be awesome :)
I would be very careful doing this. For starters a phone line only has about 2mA @ 48V in the on-hook condition (not looped) so your talking about 90-100mW all up. The reason you have to be careful is the equipment wont be approved or electrically certified (in some countries there is a huge fine for doing this type of thing) so if the telco's equipment gets damaged or you get hurt (lightening strike) its all coming out of your pocket with no legal fall back. If you want to be clever go get a few rechargeable batteries and hook them to a solar panel and run your light of that.
Well, Kipkay is "selling" snake oil to general public for a looong time. His so-called revelations range from "obvious everyday things" to "premeditated lies". I'm amazed that Engadget falls for it.
Phones run on electricity, news@11.
This is know as the chartreuse box and has been around since the 80's.
This is from the same idiot KipKay that recommended you use a DVD burner laser diode to make a high-powered handheld laser pointer, with no warning whatsoever about the fact that this light can cause permanent eye damage in a fraction of a second--before your blink response even kicks in.
and to think... back in the 70s when Mom reported getting an electric shock from the phone during a lightning storm... the phone company laughed at her and said it wasn't possible.
I'd recommend *NOT* doing this though. Sure it might be "low" amps and only 40-70 volts, but...have you ever taken a shock? I'm sure there's a lot of people out there who don't realize it doesn't take a lot of apms to die - 30 milliamps can do it, if the conditions are right (or rather, wrong).
And then, of course there's all the legal issues... I'd say if you're worried about emergency power, get an UPS.
Current drain is the prise consideration here. In the UK BT measure this in what I beleive to be a REN value. A Standard BT line can accept a REN value of 4 . Most devices (Phone/answer machines) have a REN of 1 although this is a rounded up value.
If someone were to measure the current drain when 4 phones were plugged in the you could obtain a value of maximum current that you could safely drain from the line......
But you didn't hear that from me.... alright !!
It's possible to obtain electricity from phone lines. In other news, rumour has it Nintendo is working on a video game console. I hear it uses a 6502 CPU.
First of all, it's probably been noted before, but according to this article - http://www.edn.com/article/CA6395493.html - the FCC rules say, basically, that you can only drain around 10uA from a phone circuit, which could in theory provide you with 10mA for 10 minutes after about a few weeks (that's, what, a digital watch for about a week?).
A much, much more realistic circuit that I haven't yet seen would only get "real" power from the phone when it rings. When phones were new and wall-powered, they had little bells with a solenoid-type device that pulled a hammer to the bells using a high voltage alternating current "ring" signal. That still holds true today - there's high power on the lines during a ring, enough to ring a bell with an old-fangled motor. That is MUCH more power (energy-wise) than the mere trickle you can pull when the phone's not "off the hook". Speaking of which, you should be very careful that when you do this, you aren't signalling to the phone company that your phone is off-the-hook (a low resistance signals that).
So, anyone interested in using the above-linked supercapacitor circuit to build a ringing charger of some kind? ;) Hey, maybe a cordless phone that doesn't need a power brick?