[Heath] SB-104A squirrely VFO?

[Glen Zook]

Using tinned braid from something like RG58/U works fine for repairing Heath LMOs.  There are both tinned braids and un-tinned braids that are very stiff and can cause problems.  
 Glen, K9STH 
Website: http://k9sth.net

      From: JF <lhouseparker at livingston.net>
 To: "Alexander N. Gerl"i" <ac1wye at gmail.com> 
Cc: heath at puck.nether.net
 Sent: Saturday, March 19, 2016 3:23 PM
 Subject: Re: [Heath] SB-104A squirrely VFO?
   

No, the SB-104A VFO was not pre-assembled. The twitchiness in an aged 
VFO is due to the shaft bearings eventually not making good contact 
with the frame - I seem to recall that there was a conductive grease 
in the bearings that dried out with time. The best fix was to solder 
a length of very flexible copper braid (like RG58 coax braid) from a 
clear spot on the shaft to a nearby chassis ground point. The trick 
is that you have to install it in enough of a spiral so that when the 
shaft is turned to the stops it does not pull the braid tight or bend 
the braid at the solder point.

Other wire/cable connector ground points may need to be re-soldered.

Another responder to your post recommended a URL for a tutorial for 
tube-type VFOs, and the process is similar to that for the 
solid-state VFO; however, there is one statement in it that is, IMHO, 
potentially wrong  - it says you can use tinned or untinned braid, 
but if the tinned stuff is stiff at all it will not flex well enough 
to last.

  
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