[Kenwood] TS-711A sensitivity questions

Wed, 1 Jan 2003 19:26:01 +0700

I have been attempting to recover a rather poorly TS711 for some time
now and am stuck with a sensitivity problem, the 10dB S+N:N comes in
about 10dB or more worse than spec. Would just like some confirmation
that my thinking is sound before going any further.
Reading the level diagram in the service manual suggests that there
should be some 17dB of gain between the RA terminal and the output of L2
on the RF board. I'm using a spectrum analyser with tracking generator
so I can see the shape of the filter, which looks correct, but I have
about 5 or 6 dB loss. My thinking is that the first active device is
fried but before going any further with this I want to be as sure as
possible that this is likely the case. Finding Gasfets here is
impossible so I'd like to be sure.
Any ideas as to how I might prove the device in isolation?
73's
Martin, HS0ZED