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Safety: Grandad's admonishment I've never forgotten



Original poster: "Dave Hartwick by way of Terry Fritz <twftesla-at-qwest-dot-net>" <ddhartwick-at-earthlink-dot-net>

My Grandfather, who graduated from Pitt in 1929 with a degree in EE,
admonished  when I was about 12 to always keep one hand behind my back when
working around dangerous potential levels. He and I were working on an 811A
VTTC at the time. I do this to this day--habitually and instinctively. The
idea is to prevent a charge from passing through both arms and thus through
the heart. (He was John V Heisch, 3DFW, W2KJ, W4KJ, now silent key)

Of course, this technique is not sufficient for working around the HV side
of a PDT, MOT or NST supplies--to say the least!!, but is a minimum measure
around any voltages that may be harmful.
ESPECIALLY PDT, MOT, and large NST stacks, which will kill you dead. (When I
was in the 5th grade, I managed to my hands near the HV terminals of a 12/60
NST and an arc got me. I don't know why I wasn't killed.)

I'm just saying--if you've got to stick your uninsulated hands in there,
keep one behind your back. Of course it is always best to power down prior
to intervention.

Anecdote: I was using an 1 ufd 2500 V MOT cap for a HV DC power supply
(electrostatic speakers).
Once, I somehow managed to get my elbow across the terminals of this cap
while fully charged. I could not believe the energy discharged through my
elbow--the pain. Had it passed through my arms, I'm sure I would have been
killed.

Dave Hartwick