[Milsurplus] Question abt R-270/FRR Crystal Type

[WA5CAB at cs.com]

Group,

R-270/FRR is a modified BC-794 (one of the Hammarlund SP-200 family), the 
main modification being the addition of a crystal controlled HFO that holds 
three crystals.  The manual (TM 11-896) says that the crystal types are 
HC-1/U, which apparently have no substitute out of the earlier Signal Corps 
numbered holders.  According to SIG 5, HC-1/U has two 1/8" dia. pins spaced 3/4" 
and is only 7/16" thick.

There was a post a few days ago asking for TCS crystals to use in an R-270. 
 The TCS crystal is in a 3-pin holder and is around an inch thick.  But the 
receiver owner responded to my note telling him what the manual says with 
the information that the crystal sockets in his receiver take a 3-pin holder. 
 

If anyone here has an R-270, could you please check and tell me what 
crystal sockets it has inside the oscillator box?  In case anyone has a Super Pro 
with missing nameplate, the BC-794 base unit tunes up to 40 MC and the 
presence of the crystal oscillator is identified by a small black legend plate 
and a rotary switch at the top of the front panel just to the left of the 
S-meter.

If more than one R-270 turns up with the 3-pin sockets, I will annotate my 
reprint of the TM to show that.

Robert Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480