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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