[1000mp] Inrad Front-end Mod

[Thomas Beltran]

I put the mod in yesterday, and it was quite easy.  I've been playing around
with the IF gain on different settings, currently it is at ten.   I read
that Yaesu states that one should connect an RF signal generator to the
antenna jack, and inject +8dbu, and adjust for 1 S unit on the meter.  Can
anyone translate that into microvolts?  The only signal generator I have is
old HP 606A, but I also have a Timewave DSP 599zx that measures microvolts.


Another suggestion was to set the IF gain so that the S-meter reading was
the same on the main as the sub-reciever.  On my radio, a Mark V (not
Field), the sub-receiver always had a lower S-meter reading than the main
receiver.  The IF gain was initially set at 13.  On CW, and at an IF gain of
10, there was still a consistent difference, where the main receiver is 2
S-units greater than the sub-reciever. I had to reduce the IF gain to 6, to
get the main and sub receivers to read the same S-meter readings for a give
CW signal.  Tuning around 17 meters right now, there are plenty of 20 db
signals, so this low setting has not hurt the sensitivity.  What I am
wondering though, is that the instructions show that one only reduces the IF
gain by 1 or 2 units.  Anyone else have similar experiences?  Tom W6EIJ