[Hallicrafters] Early SX-88 help needed....

[pmills7 at houston.rr.com]

I am working on a low serial number SX-88.  I have compared it with other
SX-88's of later vintage and know (what little) of I speak.  First, I have a 
manual
from the later version(s).  The unit I am working on has 2 tubes not shown 
in
this manual and both are quite obviously factory original installations. 
The first
tube is simply an amplifier for the S-meter and it is mounted in the rear of 
the
chassis adjacent to the level control pot.  The second tube, and the one 
that is
a mystery for me, is mounted on the 1st IF subchassis and is adjacent to the
12AT7 oscillator tube.  If anyone has a schematic or any info related to 
this
particular version of the subchassis, I would love to communicate with you.

thanks, 73,
Phil
W5BVB