[Amps] Odd SB-220 behavior -- help needed

[Richard]

 If the driver is solid-state, the SB-220's tuned inputs need to be 
redone with a Q of 2 - 3.  This subject is addressed in the circuit 
improvements for the SB-220 article on my Web site.  

>Yesterday, I cleaned up the input relay wiring on my SB-220.  It has been 
>modified to use a small Hi-G d'Italia vacuum relay for the input, and a 
>Kilovac HC-1 for the output.  Initially, when I did this modification, I 
>wasn't too careful with the cabling -- two of the three cables connecting 
>the input relay to the original RF input cables had their shields grounded 
>only through the relay case, for example.  I left the original RF cabling 
>exactly as originally built, and connected it to the input relay with short 
>miniature teflon coax (no more than 1" long in any case).  The input 
>pi-networks are stock, and have not been readjusted or modified at all.
>
>...

-  R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K, 
www.vcnet.com/measures.  
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