HELP, my SST howls


From: Kory Hamzeh (
Date: Wed Jul 16 1997 - 01:18:21 EDT

I just finished build my 30M SST, it seems to work well, except for the
fact that the receiver starts to howl (go into feedback or oscillation)
when I tune to a strong signal and the volume is turned all the way up.
If I back down on the volume, the howling stops. While it is howling, the
AGC LED is pegged.

This is not a stock build, I've done the following mods:

1. The PA is a MRF237
2. C10 is a 50pf trimmer. What is the correct procedure for determining
the optimum setting for C10?
3. I've done the ABX mod as described in the SST manual.
4. I've installed a 39uh choke between X4 and C10.
5. I've removed one turn from L2.

Other than that, its pretty much stock! :-)

The audio sounds a bit muddy, as compared to my Sierra. Is this normal?

Any help would be greatly appreciated.


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