Somewhat OT Knob & Tube wiring (was Re: Power and the RA82)

Paul Koning pkoning at
Tue Jul 12 14:05:22 CDT 2005

>>>>> "curt" == curt  <@ Atari Museum" <curt at>> writes:

 curt> AC "zaps" for a 10th of second at 110v isn't too bad when
 curt> crawling around running wires, it smarts and leave a nasty
 curt> tingling feeling in your teeth, makes you super wary the rest
 curt> of the day.

 curt> What is the most painful is hooking up a telco line (I used to
 curt> work for an alarm company many many moons ago) and it just
 curt> never failed that when you were wiring up the RJ31X fail-over
 curt> box to the alarm system, somebody would call into the line and
 curt> man does DC hurt and burn ...

Ring isn't DC.  The steady state voltage on a phoneline is -48V DC
(give or take quite a lot; I think the spec says the max is -60).
Ring voltage is 10 Hz AC, around 100 volts.


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