In regards to discharging the HV caps -- I never knew/thought about this
before. I have always used a "stick", in commercial amps, or a screwdriver
shaft that is grounded first to the chassis near the base of the tube, then
touch the plate connection. Hmmmm ... this sure makes sense -- Thank You,
Bill! 73 - Mark AA6DX
------------
>>> In a conventional GG amp, both B+ and B- are floating with respect to
>>> ground,
>>> except for the connection from B- to ground for the grid current meter.
>>>
>>> If the B+ arcs to ground anywhere and there is no clamping diode, the B-
>>> in
>>> instantly driven to the full negative HV with respect to ground. If your
>>> HV is
>>> 3000 VDC, the B- ;lead becomes -3000 VDC. The clamping diode from B- to
>>> ground
>>> prevents this.
>>>
>>> Incidentally, this is why one should never short the B+ to ground when
>>> trying to
>>> be sure the HV caps are discharged before working on the amp. Short B+
>>> directly
>>> to B- only, not to the chassis.
>>>
>>> 73, Bill W6WRT
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