SB-200 issues - follow-up

[Kenneth G. Gordon]

1) Grid meter works.

2) Input circuitry was apparently already tweaked by previous owner as 
input SWR on all bands tried to date is below 1.3:1. Exciter to amp 
cable NOT 50 ohm impedance at first! My mistake.

3) Loading control still seems to be at or near the fully-meshed end, 
especially on the low ends of the bands.

4) Output on 80 is lower than expected, although still adequate. Plate 
RF choke value (100 microH) is suspect. 

An interesting discovery is that the two 200 pfd grid bypass caps are 
there to make a series-resonant circuit with the tube internal 
inductances, so those who increase the value of these caps may not be 
achieving what they intend.

More later.

Ken W7EKB

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