[Amps] SB-200 Low output power on 80M - edited to fit screen

[Ian Hill - K8MM]

I have an SB-200 that putting out less than expect power on 80M. Tuning 
was done in accordance to Heathkit's instructions....basically for 
maximum smoke and reduce the drive a bit if the grid current goes over 
100mA. I expected the RF output power to be equal to or great than the 
power output on 40M and 20M, and then start falling off as you go higher 
in frequency. This has been my experience with other amplifiers with a 
pair of 572B tubes.

The tuned input SWR on 80M is 1.2 - 1.
Drive = 100W
Any thoughts what is going on?

Band   Plate V.  Plate Cur.  Grid Cur. Output power

80        1950        .460          .064          500

40        1950        .400          .094          675

20        1950        .400          .100          650

15        1950        .380          .100          550

10        1950        .460          .100          450


Thanks,
Ian - K8MM