[Asterisk-Users] False RING (incoming call) on Digium X101P FXO

[Mark Spencer]

> I was surprised to see that it's 240 volts (peak-to-peak)!  Egad.. no
> wonder it shocks fingertips.
>
> 20Hz (50ms cycle), 2 second long clean sine waveform.  I was just
> surprised to see twice as much voltage as expected.

240 sounds like a lot.  Are you sure you were doing DC measurement?
Normal is +/- 90 - 120, generally at least 48VRMS or about 70V.

Mark