"tony sayer" wrote in message
...
When I was 7 years old or so, I got a shock from the cooker main
switch on the wall. I think my hand must have been wet. The racking
spasms down the right side of my body were mercifully brief, but
it's not something I would ever want to repeat!

I got a fairly noticeable tingle when I unplugged a TV aerial lead from the
TV card in my PC while touching the metal case of the PC with the other
hand. Obviously I investigated thoroughly and tracked it down to my TV which
was plugged into the same aerial lead. It turns out that the TV puts out
about 200V between aerial ground and mains earth, though via a very high
resistance.

With a high-resistance voltmeter, I measured 200V AC but with a 1 megohm
resistor in parallel with the meter it dropped to about 100 V. Holding the
meter leads and then touching the aerial and ground there was about 50 V:
that's for a hand-to-hand resitance of about 300 kilohms.

This seemed surprisingly high but the manufacturers and trading standards
thought it was acceptible.

However I have now wrapped insulation tape around the metal aerial plugs so
that if I touch the plug again while I'm earthed I don't get a shock.