[Hallicrafters] Mixer alignment problem

[Edward B Richards]

Hi Gerry;

That is pretty normal. Some alignment procedures mention this and advise
touching up the osc last. Good luck.

73, Ed Richards K6UUZ


On Wed, 28 Apr 2004 21:54:28 -0500 "Gerry Steffens" <gsteffens at pitel.net>
writes:
> I have come across a problem a number of times over the many years.  
> It
> appears to be a problem on the lower price tiers of radios.  I have 
> observed
> it in Hallicrafters S-38E, S-120, S-108 (and maybe on S-85) radios 
> among
> others.
> 
> When doing an alignment, usually on the high frequency band only but 
> I think
> I have seen it on the third band occasionally, having completed 
> oscillator
> alignment successfully, I have found that when peaking the mixer 
> section on
> the high end of the band, the oscillator appears to be pulled by the
> adjustment of the mixer trimmer causing detuning or incorrect 
> calibration of
> the band.
> 
> I have never pursued this problem further before but have kind of 
> taken on
> the challenge this time.  So far no real successes.  I suspect some 
> stray
> coupling somewhere but where or what?
> 
> Any ideas would be appreciated and anyone else experienced this 
> problem?
> 
> Thanks & Cheers from Minnesota, 
> 
> Gerry
> 
> 
> Collecting & Restoring E.H. Scott, 
> McMurdo Silver, Hallicrafters, Zenith 
> Transoceanic and any other interesting 
> radios since the 1960s
> 
> Gerald Steffens P.E.
> Oronoco, MN
> 
> 
> Over 300 "Boatanchors" salvaged.
> Collection approaching 300 radios, 2 Oldsmobiles and a 1950 GMC.
> 
> 
> _______________________________________________
> List Administrator: Duane Fischer, W8DBF **for assistance**
> dfischer at usol.com
> ----
> Hallicrafters Collectors International: http://www.w9wze.org
> ----
> http://mailman.qth.net/mailman/listinfo/hallicrafters
>