[Hallicrafters] SX-111 RF Alignment

[wb8jkr at juno.com]

  I think I'd try aligning the coils for proper
calibration at the low end first, I'll be 
almost willing to bet the high end will be
darn close and you won't have to mess with them.
 That was the case in two SX-101A's I finished up
a few months back.

Mark  WB8JKR


On Sun, 28 Nov 2004 15:36:12 +0500 Bill Gerhold <k2wh at optonline.net>
writes:
> Gentlemen,
> 
> I am in the process of performing an IF and RF alignment on an 
> SX-111
> receiver.  The IF alignment was fairly easy and resulted in a good 
> improvement in the receiver sensitivity.
> 
> However, I have just started the RF alignment and I have run into a
> problem.
> The problem is the following capacitor oscillator trimmers.  C53, 
> 55,
> 57, 59, 60 & 63.  These trimmer caps are of a design I have never 
> seen
> before.
> They are tubular in shape.  The capacitor tuning slugs(?) ends are 
> not
> slotted to accept a tuning tool, but come to a point like a nail but
> they do seem to be threaded.
> 
> In addition, the shafts are soldered to hinder movement once set at 
> the
> factory.  I can unsolder them but I need some advice and information 
> on
> how these capacitors are tuned/turned to alter their values.  Anyone
> have any ideas on this?
> 
> 
> P.S.  The IF on the SX-111 and other Hallicrafters receivers use a
> 50.75khz IF.  I used a wonderful piece of test equipment to make 
> sure
> the signal generator was right on the money.  An ICOM-756pro.  Makes 
> a
> great piece of lab equipment.
> 
>   73 from K2WH  
> Hallicrafters, The Radio Mans Radio