[Hallicrafters] SX-122 s meter problem

[R. David Adams]

Thanks to the many responses to the problem. I ended up replacing all 
the  resistors in the rf amp, Mixer and AVC amp with 5%,  Replaced 
several ceramic discs as they attached to the places I was replacing 
resistors.  When I checked the resistors most were within 10% but m0ore 
than 5%. Several were way out.   This improved sensitivity across the 
dial, and gave me about 3/4 deflection on local stations of the s 
meter.  The meter still swings  a lot on music and voice.  It should not 
as its in the cathode of the 1650 if.  I damped it with a large cap and 
that help a bit but I am sure the readings are now off. Not they were so 
accurate anyway.
I still have about half the sensitivity on band four as the other bands, 
I checked the antenna coil and it was ok but I swapped it out with the 
one from the other set and no change.  Here is the kicker, when switched 
to band four before and after my replacing components,  the B+ 270v 
drops to 252.  The only components that switch are in the rf, mixer and 
osc circuits.  the Osc circuit is on the 150 regulated supply,   I 
checked the cathode and screen currents of the rf and mixer and there is 
no change.
At this point the radio is working well on three bands and ok on the 
fourth. these were rust buckets headed to the junkyard, so I am 
satisfied and have no more time to work on this. I redid the cabinet and 
fixed the front panel and it looks pretty good and works great mostly. 
It will find a good home I hope.  I have too Many more to do (67 of them 
to be exact), This at clears out some space for me when its gone and I 
will part out the remaining SX-122  Very good dials, good cabinet, 
transformers switch assembly etc.

Again thanks to all who helped got a lot of good ideas and implemented 
most of them.

David
jbrradio.tripod.com

Off to do a SX-100