tube prototyping safety

[Ingo Debus]

jhaible wrote:
> But what are you doing while prototyping, when you're
> working on the open circuit ? My thought would be *not*
> to attach protective earth anywhere and keep the high
> DC voltage floating, so you'd only run into danger when
> you're touching both the high voltage and the signal gnd
> at the same time. (With parts of the circuit connected to
> PE you'd be in danger just touching *one* point of the circuit.)

I'd say, as long as there's mains voltage anywhere in your
device/circuit (i.e. mains transformer included), keep the PE
connection. But if you have a seperate DC high voltage supply in a
closed box (with PE) it's safer to have a floating supply. But, as
Magnus already wrote, as soon as you hook up a scope, it's no longer
floating anyway.

The separate closed DC supply might be a good idea anyway, because you
cannot get in touch with high voltage AC anymore. Not that DC isn't
dangerous, but AFAIK AC at mains frequency is more dangerous.

Ingo