[amsat-bb] 1/2 wave bypass for 432 amp?

Bob Stewart bob at evoria.net
Sat Dec 8 18:56:06 PST 2007

My 432 brick has about a 5 DB loss on the receive
side.  I think it's the relay, but getting to that thing
would be a nightmare and I'm not even sure that 
they're still available.  I ran across K3PGP's 1/2
wave filter, and I see that it is an adaptation of the
pair of 1/4 wave lines in the old Heath HA-201 amp
that they used for T/R switching.

K3PGP's filter:

HA-201 circuit at bottom of djvu file: 

So to my question: would I likely encounter any
problems using a pair of 1/4 wave coax lines with
the diodes in the center to bypass the amp on
receive?  Has anyone done this sort of thing?  I
was thinking of putting it inside the case. Domenico, 
perhaps you?  I see your call on K3PGP's page.  :)

Bob - AE6RV

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