For decades my SB-110 would never show any ALC on transmit. The last 
time I had it on the workbench, I found that it was only putting out 
about 20 watts PEP on SSB while it would do around 100 on CW. Digging 
in, I found that the receiver diode ring product detector is loading 
down the BFO severaly, literally clipping it. I tried an emitter 
follower to drive that receiver product detector with several volts and 
then I had enough output from the transmit double balanced modulator to 
get full output on ssb along with ALC on the meter... But the receiver 
could only detect noise and single tones. Not SSB because that ring 
mixer was clipping drastically. So I put a simple series resistor, I'm 
thinking 1.5K, I don't find any notes where they ought to be... That 
relieved the load on the oscillator and drives both rings much better. I 
get full output and have a good dynamic range on the detector and the 
noise clipper (on the primary of the product dectector IF transformer) 
even works!

Years ago I replaced most of the electrolytics around the audio output 
stage with tantalum. Miniature electrolytics seem to have a far shorter 
lifetime than we hams think a radio should. I had to add some 
resistors to damp the 50 khz oscillations of the audio output tube. 
Tantalums were too good!

Otherwise the SB-110 needs attention to the grounding of boards and 
shields and it seems to plug along... One of these days, I'll put it up 
against my other 6m gear and see which hears best. I know the SB-110 has 
a lower MDS than my FT-726's 2m port... Now I have a Tentec 1209 and 
FT-736 with 6m module to compare to them... But two many other projects 
to get to that one.

73, Jerry, K0CQ
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