[Hallicrafters] SX-42 Progress

[Roy Morgan]

At 12:56 PM 2/8/2006, Rich Soennichsen wrote:
>Things are plodding along slowly with my SX-42 project.

Goof for you.. there is a lot to do to get one running again.

>This morning I wiggled the 2nd IF metal tube (for the umpteenth time ...
>still zero audio, booo... I would appreciate hearing from anyone with ideas.


Rich,

I've been helping Bob, W0YVA with his restoration:
http://www.isquare.com/personal_pages/sx42.htm **
and we've learned a couple things:

1) There are a number of variants. Just do what you can with the schematics 
you have.

2) Re: The FM IF strip:  You will find a sweep generator helpful for 
aligning this thing, but it can be done with simple equipment.  You *may* 
have to replace caps inside the discriminator can, or other IF cans.  Yes, 
it's a tough job but sometimes you gotta do it.

3) Use De-Oxit on all tube sockets. Do not use the similarly spelled stuff 
from Rat Shack. Get genuine Caig De-Oxit. www.caig.com

4) We were chasing circuit component failures and found a shorted IF 
tube.  Intermittently, shorted, actually. A sharp whack on the bench 
cleared the short, but we don't really trust that tube anymore.

5) Gear or shaft rattling in the tuning mechanism may be quieted by a drop 
or two of oil in the work. Just a  LITTLE is enough. There are concentric 
shafts and multiple gears. Contemplate carefully how it works and use a 
small screwdriver to get a drop of oil to the right place.

** At the bottom of Bob's web page on this radio, he offers stick-on 
replacement arrows for the tuning knob clutch.  I know of no other source 
for these.

If you want to refinish and re-silkscreen the front panel and/or an R-42 
reproducer, contact Bob.

Good luck,
Roy



- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
7130 Panorama Drive, Derwood MD 20855
Home: 301-330-8828 Cell 301-928-7794
Work: Voice: 301-975-3254,  Fax: 301-948-6213
roy.morgan at nist.gov --