[Hallicrafters] SX-111-- AVC mods?

[Mike Everette]

Getting back to the SX-111 -- has anyone seen an article, anywhere, regarding modifications to the AVC circuit?

I bought a nice SX-111 Mark 1 (with product detector) several years ago, which works well; but the AVC has been rather drastically changed.  Not only is the time constant longer, which makes it sound much better on SSB (no "pumping"); it has also had some silicon diodes added.  The RF Gain control seems to have little if any effect on the sensitivity, and I haven't been able to find a reason why.  I suspect that the AVC mod has something to do with this.  Maybe something is wired incorrectly; but lacking information, I'm not sure what to look for.

Any ideas?  Any leads?

73

Mike
W4DSE