[Amps] Amps Digest, Vol 212, Issue 1

[RCM]

> On Aug 1, 2020, at 12:40, dbritchie at gmail.com wrote:
> 
> Hi Mike!
> Yes - in my experience that is about what you can expect from a used SB220/221. 


Those amps, it’s power supply and tank circuit were designed when the rule was 1 KW input, and get 600 out.

With the 2400 or so volts on the plate and not the 3500 of a Henry or Ameritron, all you are doing is smoking the grids

and causing splatter over half the band.

My home-brew, with grids  grounded, 3600 v, does 1500 out with 70 w of drive, and 150 mils of grid current.