Remember our bones are made of conductive metal (calcium).As a ham radio operator for decades, I've worked on a lot of RF amplifiers. Once worked on one with 7500v on the plate.
I got shocked once on a 1800v amp. I was shorting the caps to ground before servicing it and the voltage jumped through the insulation on the screwdriver, ran through my arm and popped open a 1/4" opening on my elbow...
Be careful
Mark
I backed away from anything approaching 1000V a long time ago, my limit is 400V.
Shoog
I guess some biology lesson would do you goodRemember our bones are made of conductive metal (calcium).
I backed away from anything approaching 1000V a long time ago, my limit is 400V.
Shoog
Our bones are not made from Calcium but a Calciumsalt.
Most of the shock current,
tends to flow in the bone marrow / body fluid. The more current that flows the more burning creating carbon the pressure can build up and split/ break the bone, current increases etc. The skin resistance is the main protection but breaks down very quickly. Its very hard to completely isolate yourself from current return because the ground you stand on is Earth and resistance of shoe souls etc have an impact.
However back to topic .
Regards
M. Gregg
tends to flow in the bone marrow / body fluid. The more current that flows the more burning creating carbon the pressure can build up and split/ break the bone, current increases etc. The skin resistance is the main protection but breaks down very quickly. Its very hard to completely isolate yourself from current return because the ground you stand on is Earth and resistance of shoe souls etc have an impact.
However back to topic .
Regards
M. Gregg
Having just read all this thread, proximity activated is looking better and better!finger touch or proximity activated
Like!Having just read all this thread, proximity activated is looking better and better!
+1
Probably because the copper ones are, by and large, older. Ulyanov stopped manufacturing the copper plates in the early '80s, while they made Graphites right up until 1994.I had the biggest problem with the copper version of the GM70, the graphite plate ones on hand seem to settle down quickly and permanently.
BTW, the only trouble I've had with either was a copper plate, (but it was just one).
Strangely, the steel plate GM-70, which Foton haven't made since the '50s, don't seem to give anyone (lucky enough to have them) any trouble.
I've had the pleasure of borrowing a pair to "break them in" for a client, and they settled in quite admirably. I wish I could afford a pair! (They seem to have the "best of both worlds" – the copper plate's magic mids and the graphite's extended bottom).
And to think, all that for a technically inferior product then the graphite anode gm70's.
Funny isn't it.
Actually the iron plate version are considered by some to be sonically the most desirable. I have not yet run across any although I do look from time to time.
I have a quartet of 1960s vintage graphite plate GM70s made by "Souz" on the way. Will see what they are like when I get them.
I have a quartet of 1960s vintage graphite plate GM70s made by "Souz" on the way. Will see what they are like when I get them.
Attachments
have some experience, with 5kVdc and 2kVac BBC insulation testers.My intention WAS to invoke discussion about 1kV experiences.
those supply small current, but is enough to make your hands crazy movements!
mind the all joules in kill-o-volt tubeamp supply, you could weld screwdriver easily
yagoolar: why parafeed? :|
I converted a SE amp to SE parafeed one. Added an anode choke and PF cap - xformer remained the same) and achieved better bass response and more detailed stage. The other reason is one can easily "tune" the output changing choke-cap-xformer. Sonically - much better.
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