I am planning to convert the stock P/S in my Henry 2K-3 to a purely
capacitor filter primarily to increase the HV, but in addition some way
that capacitor filters are better for SSB. My other, newer Henry's (2K
Classic X and 3K Classic X Mark II) still use the choke filter design,
albeit with higher voltages, and never had a complaint!
My current plan, after reviewing the supply, would be to merely removing
the choke, and the .1uf 7500v resonating capacitor across it, to provide
a standard capacitor filter. The stock capacitor is an oil filled 20uf
unit rated at 5000v. The stock bleeders are 3, 20k 100 watters in
series across the output.
I am seeking 4 pieces of advice
1. What changes to the biasing is necessary with the higher plate voltage
2. Is there enough 'headroom' with the 5kv rated cap, or should I use a
higher voltage rating. Never a bad idea, but curious if it's too close
to max HV.
3. Is 60kohms too little resistance for the bleeder in the capacitor
filter design? I would like to 'cool down' the heat the amp makes at
idle, and without the bleeders playing a big part in the regulation
aspect of a choke filter, perhaps this value could be increased?
4. I have read that it's good practice to place a high value composition
resistor across the wirewounds in case they open as a backup to bleed
the cap. What value would be recommended?
Thanks, any opinions?
73 Kevin K7ZS
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