[Hammarlund] SP-600 Questions

[Wally Gibbons]

Greetings,
Am new to this list, but have quite a few Hammarlunds so thought I
better join. I also am in need of some advice on my SP-600. I pulled it
out of the cabinet the other day to get the dials to turn freely again,
it had started slipping. Cleaning and re-lubing fixed the dial slipping,
but while I had it out I hooked it to my long wire.

I've noticed that on the broadcast band, no matter where I am tuned, I
hear faintly in the backround, our local AM station on 1390 khz. My
HQ-120, 129, and SP-400 don't behave like this. The SP-600 seems
sensitive enough, I've used in to listen on 80 meters AM for a couple of
years while I get my viking II going. Shortwave has been great. On
broadcast band I've used a Palomar tunable loop. I don't see this
problem with the loop, undoubtedly to the additional selectivity. But
the long wire is overloading the receiver, I'm pretty sure.

It's a SP-600-JX-26, also labeled as a R-274/FRR.

So, it doesn't seem to have any of the "black beauties" under the
chassis. Disc ceramics, bathtub caps for the larger values. Is this AM
reception problem due to AVC leakage and the resulting RF amp overload?

It has a diode load set of terminals, and an AVC set on the back panel
which don't appear in the manual.

Any other clues as to what to look for? Does this need a re-cap anyway?
I've never had a receiver do this. Has got me stumped!


Thanks.

Wally Gibbons, WB7ASQ
rockwall@sourceoneinternet.com
North Logan, Utah