[MRCA] TDO/BC-640 Items WTB:

[WA5CAB at cs.com]

Joe,

That matches what another list member just sent me - i.e., TDO and BC-640-D 
are same, and 2-18.1 MC frequency range matches what's in SHIPS 275 and 
NAVSHIPS 900,116.  16F would be the Collins commercial or in-house number.  BTW, does 
the nameplate actually say "Model 8" or is it "TDO-8"?

The tube complement (and schematic) shown in the BC-460-B manual that I have 
doesn't match what the reference pubs list for the TDO and what I presume the 
BC-460-D manuals show.  The BC-460-B only has an 837 oscillator, 807 
buffer-multiplier and pair of 813 modulators.  The lists (which should match your 
beast) show a 6A8 oscillator, several other tubes and then the 807 and pair of 
813's.  Modulators (805's) and rectifiers appear to be the same, however.

So yes, you have a later variant.  Apparently the Signal Corps bought the 
Collins 16(*) before the Navy did.

In a message dated 11/30/2005 9:28:54 AM Central Standard Time, 
Yardleyite at aol.com writes: 
> Rob,
>        Not to confuse the matter, but it  seems my "TDO" also has a red 
> Collins "16F" ID plate on the inside of the  door, and the instructional 
> booklet 
> that is also in the inner door has "TDO" and  BC-460-D model 8 listed on it. 
> The 
> frequency coverage is listed as being for 2  to 18.1 MHZ per the Collins 
> model 16F plate. Also, the acceptance date on the  TDO plate is sometime in 
> 1944. 
> Perhaps I have a later variant. The serial number  is 321 for a model 8 TDO.
> 
> Best Regards,
>                      Joe Cro N3IBX

Robert Downs - Houston
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