roger wrote:


The filters in the computer gear were all probably legal, but there was
a lot of it and enough capacitance to bring the floating earth up to
110V on an AVO.

Tell me about it.

We had laptop once, that had been fitted quite normally with capacitors
between live and chassis, and neutral and chassis.

And a mains cable that had no earth pin or even earth wire.
In fact, AFAICR the socket in the laptop into which it plugged was a two
pin affair.

Connecting the laptop to another PC via a serial cable blew the serial
board in the PC.

yup. 110V on the chassis...and a minor misaligment brought the serial
cable 'earth' on contact with an input pin.