// The explanation that such a choke prevents HV from appearing on the
antenna (in the event that a DC blocker capacitor fails) is yet another
"old wives' tale" because typical Load capacitors arc at well under
2000v
I am surprised that such poor engineering practice is being suggested.
The protective choke is selected in the same manner as the HV glitch
resistor; both should allow the AC mains breakers/fuses to trip without
self-destructing.
All of my amps use very expensive vacuum variables as loading caps.
The idea of allowing even the "bread slicer" type caps to arc is not good
at all, as a carbon path will build up on the plates and lower the voltage
rating on the cap. For a couple of bucks, you can wind a nice robust
choke as Rich did.
Many of the amps currently in use, including the SB-1000, use very small
open frame T-R relays. You do not want the HV finding its way into your
receiver antenna input. These relays will handle the 50 ohms and several
amps of RF, but will not fare so well with HV.
I have never seen an amp manufacturer omit the protective choke,
even the cheapest of the cheap!
(((73)))
Phil, K5PC
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