[Milsurplus] Wanted to Buy: ART-13 Calibration Book

[Mike Morrow]

> I'd like to purchase an original ART-13 calibration book that fits in the
> tray beneath the transmitter.

If you have a choice (they're more scarce than the transmitters) select one
for for the specific transmitter you have.

There are cal books for:

1.  ATC-* with 8Q-1 MCW-CFI unit
2.  ATC-* with 8Q-2 MCW-CFI unit
3.  T-47/ART-13 (most with 8Q-2)
4.  T-47A/ART-13 (8Q-2, and all have a vernier scale above Dial B HF VFO)
5.  TCZ-*

I can't find my TCZ manual now, so I don't know if the 8Q-1 cal unit was used
in all versions.

Some of the calibration points shown in bold are different depending on
if the 8Q-1 or the 8Q-2 is used.

The USAF used the T-47A, which always uses the 8Q-2 and also has a
vernier scale above HF VFO knob B to aid in more precise dial positioning
than all other models.  Cal data is given in 1 kHz increments throughout
the whole frequency range in T-47A (AN/ART-13A) units, while for the other
versions it is given in 5 or 10 kHz increments.  Thus, the AN/ART-13A book
is more than twice as thick as the cal book for other versions.

The early AN/ART-13B did not have the "LF Frequency Extension" switch on
the front that allowed crystal control operation down to 1670 kHz.  The
CDA-T has 20 MF/HF crystal positions, but they are really ten channels
in bank A and ten in bank B, in which at any of the ten channel positions
the A frequency and B frequency must be, IIRC, within three percent.

Any AN/ART-13B could have been built on any of the earlier models, not
just the T-47A/ART-13.  In fact, most seem to have been made from USN
ATC models.  The cal book that is appropriate is the cal book for the
original version.  The best case would be a T-412/ART-13B that was built
from a USAF T-47A/ART-13.

Other than cal points or the precision of dial settings specified in the
cal manual, all cal data is the same regardless of the model.  The cal
book data were not specific to any model or serial number, like the books
for the BC-221 or the LM frequency meters, even though the cal books may
themselves be serialized.

Unless one has the cal book for the specific transmitter model, I don't
see any value of any substitute above just using the cal data that is
available in any copy of the appropriate operating or maintenance manuals.

73,
Mike / KK5F