Re: [Amps] 3.5 kV 2A REGULATED Power Supply: Schematic ?

[Gary Schafer <garyschafer@comcast.net>]

Dr. William J. Schmidt, II wrote:
>  <<**  Ian -- For AB2, yes, but for AB1, control grid V-stability matters not
> since there is no grid current. >>
>
> Look.  It does not matter if the tube draws grid current or not.  If there is
> any signal impressed on the grid voltage via any means, it can lead to
> distortion.    It’s a simple concept.  Regulation of the bias voltage is one
> way, then, to ensure that it does not happen.  The better regulated the bias
> supply is (e.g. the lower the Z of the supply) the less likely this is to
> happen.  Here is a test:  will the amplifier's unit impulse or step response
> will be different with poorly regulated supplies?
>
>
> Sincerely, 
>
> Dr. William J. Schmidt, II K9HZ
> Trustee of the North American QRO - Central Division Club - K9ZC 


I guess that is something that Collins Radio engineers did not know?
They produced thousands of 32S1 and KWM2 radios with no regulated bias 
supplies.
Lots of others too. Every SSB radio with 6146 finals in it that I can 
think of uses no regulated bias supply. Bias is fed by a large value 
resistor to the grids. bias voltage is free to swing as it pleases when 
the tubes are driven into grid current.
10k to 20k resistor in series with the bias supply would hardly be a low 
Z supply.
They are to be run in AB1 though.

73
Gary  K4FMX


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