[Hammarlund] HQ-180 problem seems to be fixed

[Bob Camp]

Hi

If you want to cool off the radio, a light weight fan is by far the best approach. If you mount it with cable ties, it’s easy to reverse.

The biggest heat related issue on tubes is the seal (at the pins) and leakage (like air into the tube). Cooling sheds don’t do much for this. Fans are not a whole lot better. Ceramic tube sockets can help. 

Yes, things other than tubes run around in radios. Yes they fail quicker when hot. Fans help them a lot more than tube shields do. 

Bob

On Sep 27, 2014, at 12:30 PM, Robert Sauvan <rsauvan at beyondbb.com> wrote:

> Well,
> After sifting through everyones suggestions as to what to do to go about fixing my AGC problem, I believe I hit on the source this morning. I think we could consider it the most basic "radio restoration 101". It turned out to be a dirty AVC switch. As I was carrying the thing back to my workbench this morning to continue troubleshooting, I had the cover off and looked down and noticed the AVC switch was plain as day. It looked a little crusty and quite frankly I dont remember ever cleaning that switch from when I purchased the radio. So, I cleaned the heck out of it before firing it up on the workbench again. After a thorough cleaning, turned the radio back on a "voila" clear nice sounding cw signals again. I now feel I have the radio sounding as it should. As WA2CWA pointed out, the audio isnt the greatest on these units and I feel it is back to square one now as built many years ago. Now that it seems right, I want to try that mod in the ERM article. I am waiting to get a copy sent to me and will let everyone know how it turns out if I should decided to try it.Thanks for everyones help once again. Another great educating moment. Now, for the tube shield inquiry, I might just try the black paint process just for the grins to see if I cant make this radio run just a bit cooler.
> 
> 73-Bob-W0YBS
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