[RTTY] Heathkit SB-1000 On RTTY

[Bill, W6WRT]

ORIGINAL MESSAGE: 
On Tue, 25 Sep 2012 11:31:02 -0400, W4TV wrote:

>Plate current is plate current, plate dissipation is plate dissipation
>no matter what the class of operation. In fact, since an amplifier is
>slightly more efficient in Class C than in Class AB2, the tube should
>be derated even more in class AB2 than in class C.

REPLY: 
You're missing the point. It's not just the class of operation, it's also the
mode of operation. Class C plate modulation is far different from Class C CW or
RTTY operation. With Class C plate modulation the instantaneous plate current
and plate voltage swing up MUCH higher than the no-modulation condition. That's
why PLATE MODULATION ratings are so highly de-rated. 

In our discussion regarding the SB-1000 all the above is irrelevant anyway since
the SB-1000 does NOT run class C.   Use the specs for class B (older data sheet)
or class AB2 (newer data sheet) and you will see the tube is fully capable of
600 watts RF output. 

73, Bill W6WRT