[Hallicrafters] SX-100 update

[David L. Thompson]

I have gone through the SX-100 and it receives on all bands.  The main
tuning dial is way off (40 meters lines up at 6950 rather than 7500 where
the diamond is located).  All bands are off in similar fashion.  Once I get
each band set on the main dial the bandspread falls in place fairly close.
I found an old TV balun that I had soldered a coax connector to (its from
Drake) and used that to hook my antennas to ant 1 and 2.  It sure makes a
difference.  I was listening to W1AW and had to reach for the volume
control.  I also went to Radio Shack and bought two #44 bulbs as the bulbs
on the bandspread dial were out. The dials work fine so don't have the
problems with the inserts that have been discussed lately.

I still have to check the T notch filter but just tuning it on CW did not
seem to do anything.  The S meter does not seem to work.  Throwing the
receive/transmit toggle switch does make the S meter jump back a little.  I
will check out the wiring and the meter.  Turning the S meter adjust pot on
the rear did nothing so I will see if works.  I found such a pot was shorted
in another receiver.

Several reported the S meter should work on SSB as long as the AVC is
switched on but the manual is quite clear that you need to be in AM mode to
get it to read and the sensitivity (RF gain) on 10 ( all on).   I wonder if
this is a mod in the later models. The QST review only mentions the S meter
but gives no clues.

The manual says SX-100 Mark I A.  I cannot find a serial number anywhere.
There is a number 3B with a five digit number on the metal over the S-meter.
This number does not match the parts list so its a possible suspect.
Usually the number is on the rear but the piece of paper that was attached
is torn off.  I looked over the chassis with no luck for any other numbers
except parts numbers. The original note saying the RX was aligned at the
factory is still attached to the bottom of the case.  But it has no model
info and appears generic.

I will get back to the Sx-100 next week.  Thanks for all the comments so
far.

73 Dave K4JRB