[AMRadio] HQ 180 problem

[Pat Thompson]

The gentleman that suggested checking the IF voltages at the tube bases 
has identified a common problem.  It also can't hurt to do some signal 
tracing if you have a generator.

If you do have a problem internal to an IF transformer they can be 
repaired with lots of patience and finesse. I repaired a can in a HQ-170 
so it can be done. Another symptom of silver mica disease is random loud 
static crashes without the antenna connected.

see:

http://www.antiqueradios.com/forums/viewtopic.php?t=5150&start=20

http://amfone.net/Amforum/index.php?action=printpage;topic=18748.0

Also search YouTube for Hammarlund IF repair.

I would soon replace all electrolytic caps. There is room under the 
chassis for modern types wired to a terminal strip. Leave the FP style 
can on the chassis but disconnected.

Pat
wa4tuk


On 1/20/2013 6:16 PM, Robert Sauvan wrote:
> Hi all,
> I just acquired a Hammarlund HQ180 C from a buddy of mine. He indicated
> that he didnt know whether it worked or not and had never plugged it in.
> Well it doesnt work of course. I am hoping for a little help to guide me as
> to where I might start to look for a fix by explaining the symptoms. I
> realize it is difficult if not impossible to pinpoint anything but I am
> hoping maybe someone has had similar problems, or maybe these receivers
> have a common glitch to look for.
> Here is what happens.I turn it on, it lights up, the S-meter will climb to
> about 2/3 scale and after a few seconds it will drop back to zero and never
> climb again. the radio has a constant hiss but does not have any signals to
> be heard. With and without the antenna hooked up, it doesnt change. The
> calibrate tone cannot be heard either at 100 kc increments. When put in AM
> receive mode, it hums. I have pulled and tested all of the tubes, I
> replaced 3 of them so I think we can cancel those out of the equation. All
> of the switches have been cleaned as best as possible for the moment. I am
> hoping to get some suggestions as to where I might start probing into
> troubleshooting this thing in hopes of cutting down on just going point to
> point and then finding that it was the last thing I checked. I know this is
> a loaded question, and I will probably get a different answer from each
> person, but Im willing to see what becomes of it. Let me know what you
> think.
>
>
> Thanks-Bob-W0YBS
> ______________________________________________________________
>