[Hammarlund] Silence below 7.4 Mcs

[James A. (Andy) Moorer]

on 4/22/02 1:32 AM, Clemens S.Ostergaard at clemens@it.dk wrote:

> Dear list-members,
> 
> My trusty Sp-600 JX-17 s/n 17366 gave up on the three lowest bands the
> other night. No meter reading, no audio apart from background noise. I
> remember advice on what to do about the opposite problem, silence above
> 7,4, and I also seem to remember ideas about what to do about my problem. I
> have not changed any valves, and before I start looking at the receiver,
> I'd just like to ask the assembled wisdom about the likely cause. Works
> perfectly well above 7,4 .
> 
> Best,
> 
> 
> Clemens S.Ostergaard
> Aarhus
> DENMARK
> 

The first thing to try is V7, the 6BA6 that is used as the gate on the low
three bands. It could also be V6, the second mixer (6BE6), but less likely
since it would have to be an internal short, in which case it is not clear
why it would be working on the high three bands.

I had a problem like that one time that I finally chased down to a bad
capacitor, C69, which is inside T1. I hope that isn't your problem.

Best of luck!


-- 
James A. (Andy) Moorer
Adobe Systems