240volts and ground hum problems.

[Ingo Debus]

Martin Czech wrote:
> The mains filter must be grounded to protective earth. It would be useless
> and dangerous otherwise.

The Y capacitors (those from the two mains lines to the chassis) are
there to keep the common-mode high frequency dirt from entering the
device. Protective Earth is not required to perform this task.
I don't think it's illegal to have Y caps in a device without PE. If
this were the case, I'm surrounded by lots of illegal gear =:-)

Ingo