[Hallicrafters] SX-100 Pass Band

[Jim Liles]

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


-----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

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