Quoting "Joe Subich, W4TV" <lists@subich.com>:
No, recommending the removal of protective devices and removing them in
amplifiers you service is ridiculous.
Joe,
Relying on ANY protective device around High Voltage is putting your life
in someone else's hands.
Bleeder resistors fail
Shorting bars fail
And YES, even shorting sticks can fail
In over forty years maintaining Broadcast Television transmitters,
I've seen them all fail.
I carry a pair of automotive jumper cables with me anytime I go into
any transmitter. One for the DC and one for the AC.
Then, I check all the circuits with TWO volt meters.
Extreme ? Possibly......... but I'm still here.
Working on any ham amp, I'd recommend that they be unplugged for 24
hours unless someone knows with absolute certainty that they know how
to properly
discharge every capacitor and high voltage terminal.
I'd also recommend that they be placed on a bench that doesn't have a
tempting ac power plug close by.
If you can't troubleshoot with a digital ohm meter, then you sure
don't need to be working on a circuit that is hot.
I just got in from repairing a BE 20 KW FM transmitter that had no
screen voltage . It took quite a few measurements with an ohm meter
to decide that a wiring harness had an open wire ..... 220vac wire to
the screen transformer had arced to chassis and then opened up.
I'm training a younger guy , so I am having to " re-educate " him and
his troubleshooting methods..... HE wants to run 100 mph in six
directions.
I have to sit him down and tell him to take twenty slow breaths.
Then I asked him where he planned to be tomorrow ....
"Home", he said.
"Me too" , sez I.
"Now turn off the main wall breaker and get those jumper cables out of
my trunk".
Don W4DNR
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