"Dan/W4NTI" w4nti@get rid of this mindspring.com wrote in message hlink.net...
"Michael White" wrote in message


Do it this way; Tune amp up normally at full power on SSB mode, or CW
mode.

Note the Grid and Plate current readings.

Reduce drive, as you have been doing. But RETUNE the amp at the lower drive
level. Reducing the drive as needed to maintain a level of 50% or less of
the full output readings.

See if that don't fix you up.

Dan/W4NTI

Probably won't help too much. I didn't in my case with that amp, when
I tried reducing the loading. 300w "1/2 power" is a bit high for
continuous duty SSTV. I would cut that in half to about 150w. I've had
the sb-200 and also the fl-2100b. They both are hot running amps. The
plate dissipation is only 320w compared to 1000w for a pair of
3-500z's. I would mount a fan on top to help cool a little better.
Heck, with my henry 2k classic, I only ran 300-400w for SSTV. "The amp
does about 1300-1400 w. " And the tubes would start to blush a little
on it. MK