[Hallicrafters] SX-100 Pass Band

[Al Parker]

Hi David, Chris:

The instructions are nebulous.

When they say center the generator for the center of the pass band they 
are speaking of the 50.75 I.F. using the 5kc bandwidth not the 1650kc 
I.F. pass band.

The essence of this adjustment is to feel around with the 1650kc signal 
generator looking for the start center and end of the 50.75kc pass band 
which is set for a 5kc width.  When you find it, you center the 1650kc 
signal generator to the center, and simply peak the 1650kc transformers. 
The skirts that you are listening to are actually the 50.75 skirts not 
the 1650kc passband which is significantly wider.

Note:  The 1600kc and 1700kc crystals could be somewhat off and usually 
are. The 1650kc band pass is WIDE enough to allow for significant 
deviation from the 1600 and 1700kc cuts.

The 1650kc pass band is going to be (never found a reason to measure it) 
far wider than the 50.75 kc pass band.  This will allow production grade 
tolerances for the crystals.

Hope this helps and if not let me know and Ill rewrite it.

Kindest regards Jim K9AXN

later Jim says:
Good morning again David:

I sent a note hopefully clearing up the instructions in the manual for 
the 1650kc alignment procedure.  There is a simpler way.

OLD TIMERS WAY:
Use your signal generator to inject a modulated signal i.e. 3600kc NOT 
1650kc into the antenna terminals.  Sense as in the manual, set the band 
width to 5kc, LSB, and tune the receivers frequency dial back and fourth 
to find the center of the 5kc pass band, then peak the 1650kc 
transformers ----  Done.

Kindest regards Jim K9AXN
=================================
-----Original Message----- From: David C. Hallam
Sent: Wednesday, July 10, 2013 7:50 AM
To: Jim Liles
Subject: SX-100 Pass Band

Jim,

For the SX-100, do you know how many dB down the pass band skirt, the
1600 and 1700 KHz oscillators should be?

David
KW4DH