[Boatanchors] [Hammarlund] HQ-170 audio

[RAY FRIESS]

Pat:
 
Assuming it is the caps, wouldnt the noise be there all the time?  Wouldnt it affect the receivers ability to receive?
One thing I have noticed is that the crashing or static noise and the microphonics seem to appear once the receiver has warmed up.
And, there are times it is not there, sometimes for extended periods of time.  Again, similar to my earlier experiences with tube equipment
which had noisy tubes.
 
If the caps were bad, would the receiver continue to receive and be as sensitive as it should be?   the static crashes are like one hears when
trying to conduct a qso with a thunder and lightning storm going on around you.   That kind of noise and crashes.    the microphonics are classic
reverbs and bumps when tapping on the front panel or cabinet.    
 
the receiver even holds its stability and doesnt drift at all.    It functions perfectly with the exception of the static crashes which make it sound like
40 meters in a rain storm .. HI HI.    and also the microphonics.
 
Ray
 
> Date: Sun, 20 Feb 2011 18:51:58 -0500
> From: wa4tuk-rf at comcast.net
> To: rayfrijr at msn.com
> CC: 1oldlens1 at ix.netcom.com; hammarlund at mailman.qth.net; boatanchors at puck.nether.net
> Subject: Re: [Hammarlund] HQ-170 audio
> 
> There's a failure mode in the IF cans where the internal mica caps short 
> out. A symptom is loud crashing or static noises. It's something of a 
> pain to replace these caps but it is possible.
> 
> Pat
> wa4tuk
> 
> 
> 
> On 2/20/2011 6:35 PM, RAY FRIESS wrote:
> > The microphonics are still present even with the volume control all the way down.
> > The noise (static like crashes) decrease with the volume control all the way, down but are still present, just barely though.
> > By microphonics, I mean that when I tap the cabinet or front panel, you can hear the coming through the audio section.
> > Before the noise started in the audio section, it was not present.
> >
> > I have had the receiver gone completely through by an expert in Hammarlund receivers. When he sent it back after going through it,
> > he said it was as close to factor specs as he had ever been able to get a receiver of its age to.
> >
> > Ray
> >
> >
> 
 		 	   		  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://puck.nether.net/pipermail/boatanchors/attachments/20110220/4b59e0e9/attachment.html>