[Hallicrafters] SX-117 slave mode

[james.liles]

Hi Skip,
First verify that the radio is wired to the "E" suffix schematic.  Then use 
service bulletin 1964-4 June 1, 1964 to make the cable that connects the 
SX-117 and HT-44.  The length and type are critical!!!  The capacitor that 
replaces the tab cap is 1.5 - 9 PF NPO temp comp.  Anything close will work 
but must be NPO.  If you need the service bulletin, I can scan it and send 
it to you.

I overlooked the serial # ending in 1.  I believe that is a run2 or B suffix 
radio.  The B to C changes were significant and were included in the C-169 
change letter.  Improves the radio significantly.  Note, the AVC tap change 
on the C level radio causes it to respond to signals that are out of the 
final IF band pass --- also causes the S-Meter to see things that are not 
yet audible.  Kindest regards Jim K9AXN



Original message:

Message: 1
Date: Wed, 2 Jan 2008 14:12:59 -0800
From: Waldo Magnuson <magnuson at mac.com>
Subject: [Hallicrafters] SX-117 modification for use with HT-44
To: hallicrafters at mailman.qth.net
Cc: Waldo Magnuson <magnuson at mac.com>
Message-ID: <E05FB502-B97F-11DC-B8F3-00039315EF26 at mac.com>
Content-Type: text/plain; charset=US-ASCII; format=flowed

    I have been trying to solve the problem I have with frequency
stability when using the HT-44 in slaved mode with the SX-117.  The
HT-44 manual has "SX-117 Notes" on page 14 of the manual.  Note 2
states that on sets below s/n 117004 (mine is 117001) the replacement
of the brass compression trimmer by a silver ceramic type capacitor
should help with VFO drift or long-term calibration.
    My question is - has anyone made this modification and what value
ceramic capacitor was used?  Thanks.
73,  Skip W7WGM