The FCC did it!
Originally the rule was 1000W DC input for any mode. Then it changed to
2000W PEP for SSB only so the plate transformer was tapped and a switch
added,
Some of those older amps have a pretty wimpy transformer and not suited for
heavy duty CW use in the SSB position.
The Ameritrons with that switch change the bias but it never goes into
Class C. Instead it is in fairly Deep Class B in CW with a much lower idle
current which also works well in AM. The HV doesnt change.
Carl
KM1H
----- Original Message -----
From: "Charlie" <charlie@drhabekost.com>
To: <amps@contesting.com>
Sent: Monday, January 11, 2016 1:16 PM
Subject: [Amps] Need for bias switch (CW/SSB)
Folks-
I am putting a 8877 amp together. I was wondering why some amps have a
"CW/SSB" switch.
Assuming the power supply can handle cw key down, other than higher
efficiency, what other reason could there be for this switch?
Thanks!
Charlie N6CFH
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