[AMRadio] My BA Station: HQ-170 and Globe Champ 350

[Kim Elmore]

I'm happy to say that refurbishing is now complete for both units! 
These had been my Dad's (W5JHJ SK) since 1959 and I obtained them 
from the estate about a year and a half ago.

Both units worked when I got them, but i wasn't certain of their 
overall condition. The Champ needed a bit more attention than did the 
Hammarlund: there had been some hot resistors in it and there were 
some "olde" electrolytics that needed replacement. I also replaced 
some questionable silver micas in the Champ. As my dad had kept 
everything in working order, the job wasn't too bad. I also added SS 
rectifiers to all the rigs, then bypassed the DC path through the 
filament supply for the B+. This helps a bit with regulation and 
removes a tiny bit of load from the PS transformer, though probably 
not enough to worry about. Removing the hollow state rectifiers does, 
however, reduce the overall heat load incurred on both units.

The Hammarlund HQ-170 was an easier project: I replaced all 
electrolytics in it, but everything else seemed in good order. I 
finished a complete alignment on it this morning using a Ramsey 3010 
service monitor loaned to me my K5KUK. The RF alignment proved most 
tedious as it sets the band spread, so there's interaction between 
the high and low ends of the bands. Of all the bands, 20 m proved the 
worst in this regard and I had to go back and forth several times. 
This includes trying to compensate by "cheating" either high or low 
(as needed) on the band edges to try to converge a bit faster on the 
proper alignment. But, I finally got it all as it should be.

I found that the 455 kHz IF was out of alignment by a fair bit, 
almost as if it had been aligned about 1 or as much as 2 kHz low in 
frequency. The 60 kHz IF was in good shape and the 3056 IF was only 
out a little bit. The RF alignment was off a fair bit and the antenna 
coils were out by quite a bit. It may be that when he last aligned 
it, my dad forgot to center the antenna trim capacitor. The 
Hammarlund is as sensitive as I remember: with just the probe from 
the service monitor on the antenna input I could hear the 10 m CW 
contest banging away.

I left the multi-section can capacitors in place on both units for 
cosmetic reasons. All new electrolytics went under the chassis.

I need to get some pads for the bottom of the Hammarlund chassis, so 
that I don't  scratch up my desk top -- they are already on the 
Champ. I'll install my new antenna switch so that I can choose either 
my Tentec Orion II, my venerable old TS-930S or my boat anchor gear 
and then squeeze it all into place. It will all be easily ready by Christmas.

I must thank W5JO profusely for all of his suggestions, help and 
encouragement over the time it's taken me to finish this. After a 
self-imposed problem with the Champ (I failed to solder a capacitor 
lead on the driver matching network) all else went swimmingly. At 
Jim's urging, once I had the Champ up and going I tested the audio 
bandwidth of the transmitter and found the -3 dB points are at 280 Hz 
and 5.4 kHz -- not too shabby.

The only mic I have wired for it is an older Shure 404C hand mic. I 
have a Heil double-element desk mic that has a flatter response, but 
need to make an adapter so that I can go from the 9 pin mic plug to 
the 4 pin plug my dad put on the Champ. Yes, the Champ originally had 
a two-pin mic plug, but as an ex-BC engineer he was very particular 
about his low-level audio paths. I'm hoping that it sounds pretty 
good when I finally get it all going!

Merry Christmas,

Kim N5OP