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It Seemed Like A Good Idea At The Time

By Jack-M ·
The idea for this topic came from the answer "muzhik" gave to the Tshirt question.
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It seemed...etc.
I used a metal probe to find a twisted pair that had tone on it in a telco central office and bumped the wrong thing. DC voltage knocked me back 15 feet to a concrete wall. at the time....
Jack

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Another Phone Story

by cmiller5400 In reply to It Seemed Like A Good Ide ...

One of my former coworkers was trying to tone out a phone jack and instead of using the toner he was using his finger and was holding the toner listening for it. Well, one of the lines must have had juice running in it because his hair stood on end for a short while.

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HiCap

by zdnet In reply to Another Phone Story

Sounds like your coworker found an uncovered HiCap, 48volts, that's why they put those annoying little red caps over them....

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Phones use electricity?

by Tink! In reply to It Seemed Like A Good Ide ...

Yea, you don't realize how much charge those things use until you accidentally touch the wrong spot and get shocked. (twice)

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Careful-- Phone lines can BITE

by mjd420nova In reply to It Seemed Like A Good Ide ...

I guess maybe the phone technology has gotten left in the past. Phone lines are 48 volts DC, and can really knock you on your butt. That 48 volts comes from the central office, and is backed up by rooms and rooms of batteries. That's why I still have the old style tone dial phone that plugs to the phone jack and that's all. When your power goes out, kiss the cordless, answering machine and the fancy stuff goodbye, they need power. The light up dial works even when the whole city is dark. That 48 volts might not kill you but could weld you to ground if you don't watch out.

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48 volts with no amperage

by Jack-M In reply to Careful-- Phone lines can ...

Phone lines are normally,in either talk or idle mode, 48 volts with about 0 amps. But ringing voltage and amperage is a diferent story. I could run a mainfram in a jiffy using my finger and holding the alligator clip in my closed fist.
No clicking on the customer's line, no interruptions of alarm circuits etc. But hit a phone that's ringing and you'll say OUCH! every time.
Jack

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Ouch is right

by Don Christner In reply to 48 volts with no amperage

One time I was adding a phone in my basement. Of course I didn't bother to use the right tools, teeth make a good wire stripper, right? Not when you're stripping a wire and receive a phone call. My tongue hurts just remembering it!

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Phone ring voltage

by pinroot In reply to Ouch is right

Phones operate on 48V DC (Positive ground, or it was at one time). However, ring voltage is (or was) around 100VAC (it varies depending on your distance from the Central Office in the home), 20Hz. It's not much different than sticking your finger in a 110VAC light socket. :)

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VOIP out, too

by TrueDinosaur In reply to Careful-- Phone lines can ...

In noting that the fancy stuff does not work when the power is out, VOIP was not mentioned. It will also be out when the power dies. Unless you have a small UPS for the modem. This makes me ask, is DSL signal still available if the phone works? And what about cable based internet service?

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UPS on the cable modem & VOIP

by Too Old For IT In reply to VOIP out, too

I have a slightly elderly (but with good batteries!) APC 1200 on the Cable modem, Vongage box and router.

Newer one upstairs under wife's PC, portable phone, upstairs switch.

Amazing what stays on when the neighborhood goes dark.

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How long...?

by noyoki In reply to UPS on the cable modem & ...

How long do you get with the UPS? We just had a power outtage in Queens (near NYC) late July - some people had no power for over a week...

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