[Collins] 75S-1 Problem

[Jim Brannigan]

Jerry,
As a benchmark, subject to a lot of variables,  the 100kc calibrator should
produce a S9+ 20db response on 20M.

Jim

>
>
> Thanks to all that replied!
> Tried it terminated into 50 ohms, no change. I had to drop the signal to
10
> micro volts to get S-9. URM-25 might be way out of calibration, I'll try
it
> with  the HP 606B. Even though, RX is still way too hot. Just  about every
> signal pins the meter. Maybe it's over coupled. I did not use  the
"swamping
> network" (1K res. and .01 cap.) when I aligned it. All tubes  are correct,
no mods,
> all paper and electrolytic caps had been replaced a few  years back. I
tested
> all the tubes (mostly looking for  gas/shorts/leakage) and found a couple
that
> had some heater to  cathode/plate leakage, replaced them and the signal
> levels went even higher.  Bias seems to be working OK (I can cut RF gain
via the
> front panel  control, re-zero the meter pot and make signal levels more or
less
> normal).  I'll give it another shot with a better sig gen and use the
swamping
>  network.
>
> Thanks again for all the info and 73! DE N5MCJ,  Jerry