In regard to the input swr on the sb220 and for that matter most of the
older amps, one must remember that they were designed and built when most
all exciters were tube types and therefore had pi-network outputs, most of
which could match a fairly wide range of impedances, so the lousy input swr
situationn was not too noticeable or bothersome. that isn't the case today
with solid state rigs. some people have indeed used 'antenna tuners" between
the exciter and the amp. that works to some degree, but it's only a bandaid
type approach. One needs to get into the amp and re-tune the input
circuits, AND increase the Q of the ckts also. there are a number of sources
of info on how to do that. Rich Measures has written articles on that and
the arrl handbooks have that info also. I have re-tuned a number of sb
200's- sb201's- sb220's and they all suffered that same problem, ie: hi
input swr and very low Q ckts.All those old amps are still good amps, but
they do need to be modernized.. 73 carl / kz5ca
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