[Boatanchors] R-388 51J3 & Mech Filters

[WA5CAB at cs.com]

Getting back to the subject subject, Collins made an adaptor to add up to 
three mechanical filters to the 51J-3 (R-388/URR) and 51J-2 S/N 501 and above.  
It mounts in the area originally occupied by V107 (1st IF Amp) and T103 (1st IF 
Transformer).  It includes two 6BA6 tubes, one on the input and one on the 
output.  So technically, the receiver so modified would have four IF amplifier 
tubes.  The instruction booklet says that one of the tubes was added to make up 
for the insertion loss of the filter(s).

I have the instructions but have looked for years for one of the kits with no 
luck.


Robert Downs - Houston
<http://www.wa5cab.com> (Web Store)
MVPA 9480
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