[MRCA] Looking for TA-12C

[J Forster]

If anyone wants a .pdf manual for the RA-10DB, there is a downloadable copy of my 'Specific Apparatus Description' the Canadian version of the Bendix book on the RoyalSignals.org.uk web site. Look under Radio Aids to Navigation.

-John



Mike Morrow wrote:

> I wrote:
>
> >The TA-12C provides LF/MF, and MF/HF coverage to 12 MHz in four *non-overlapping*
> >bands.  In comparison, the TA-12B provides LF/MF and HF coverage to 7.7 MHz in
> >four bands with wide overlap.  That allows the TA-12B to be tuned to more preset
> >HF channels in the useful 4 to 7 MHz range than the TA-12C can accomodate.  Plus,
> >RA-10DB coverage ends at 10 MHz, so TA-12C coverage of 10 and 12 MHz would have
> >been pretty useless.
>
> I should proof-read more before posting.  TA-12B coverage ends at 7.0, not 7.7 MHz.
>
> To summarize, here is the coverage in kHz of these Bendix units:
>
>                 TA-12B           TA-12C
> Channel 1    300 to   600     300 to   600
> Channel 2   3000 to  4800    3000 to  4800
> Channel 3   4000 to  6400    4800 to  7680
> Channel 4   4300 to  7000    7680 to 12000
>
>                 RA-10DB
> Band 1       150 to   400
> Band 2       400 to  1100
> Band 3      2000 to  5000
> Band 4      5000 to 10000
>
> The RA-10DA is identical to the RA-10DB, except that it does not come from the factory with circuitry to support DF loop antenna connection for bands 1 and 2.
>
> Since the most commonly used aircraft frequencies during the early 1940s were below 7000 kHz, TA-12B frequency coverage (with large overlaps on channels 2 through 4) would appear to have been more generally useful than that of the TA-12C.
>
> Mike / KK5F