On Wednesday 18 November 2009 4:49:11 pm Mike & Coreen Smith wrote:
> Has anyone ever added the extra position bandswitch wafer ...
I did this to my SB220 by cannibalizing an extra switch wafer to move
a set of contacts to add 160 along with the other bands. Added an
extra set of contacts to throw a relay to add a cap to the loading
control. Never got around to building a PI network for the input
side, so you had to drive it hard to get a gallon out. Also, had to
add capacitance to improve bypassing, and had to wind a better plate
choke. Finally, the filament choke needs to be upgraded. But it
mostly works.
Blew out the plate transformer, so got a Peter Dahl substitute.
Haven't used that amp in a while, bet I need to pump down the tubes
again :-)
Victor, K1LT
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"160-meters is a band for men, not for sissies!" - SM5EDX
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