On Sun, 23 Aug 2015 20:29:21 +0000 (UTC), N_i_c_k wrote:

But remember that BT put 1kV into the phone cable at random
intervals to discourage DIY.

That's shocking.

I can assure you the normal 50 V DC on a Direct Exchange Line
(ordinary phone line) is pretty shocking when you are up a ladder
putting on the talkback, music and control lines for an outside
broadcast in the peeing rain with you, the block and everything
soaking wet.

--
Cheers
Dave.