[Milsurplus] ATC vs AN/ART-13

[Mike Morrow]

Jack Antonio wrote:

> Just wondering if there are any differences between the ATC
>and the AN/ART-13. 

Hi Jack,

I'm no expert, but here's what I know:

The earliest units were under the old USN nomenclature of ATC and ATC-1.   I believe these are identical except for the contracts under which they were procured.  The T-47/ART-13 followed under the JAN system, and it also was identical to the ATC.  In fact, many ATC units have painted stencils of "T-47/ART-13" on them along with their original ATC name plate.  Some of the early units may have the first Collins type 8Q-1 MCW audio oscillator and calibration frequency indicator units, but most will have the later 8Q-2 MCW-CFI unit installed.  These units were usually pared with a DY-11 or -12/ART-13 dynamotor, an O-16/ART-13 LF VFO, and a LF external tank coil CU-25/ART-13 or CU-26/ART-13.  Many USN models used the early MT-161/ART-13 transmitter mount.

The USAAF/USAF procured the T-47A/ART-13, used it with a MT-283 mount on transmitter mated to MT-284 on shelf, used an O-17/ART-13A LF VFO, CU-32/ART-13A LF tank coil, and DY-17 or -17A/ART-13A dynamotor.

The major difference between the USN and USAAF systems, other than the reduced frequency range of the O-17, and the fact that all T-47A units should have the 8Q-2 MCW-CFI, was an interlock switch on the T-47A that stopped the dynamotor when the top lid was removed, and the vernier-type calibration marks on the HF VFO dial that allowed settings at one-tenth of a division, which was not possible with the USN units.  Also, I believe most USAAF units had a calibration manual captive chain that I've never seen on a USN unit.  The calibration books were also a little different in content between the USN and USAAF units.

Then finally, the T-412/ART-13B was developed for the USAAF, which allowed twenty crystal controlled channels in the MF/HF range and four crystal channels in the LF/MF range through the use of a CDA-T unit in place of the LF ocsillator and a significant amount of internal transmitter channel switching circuitry modification.

> Are the units interchangeable, was any circuitry revised between the two units?

In essence, all these units are interchangeable.  A T-412 used with an unmodified C-87 control box would only be able to select 10 crystal channels.

> Can you repair an ATC using an AN/ART-13 manual? 

Certainly, since the ATC and T-47 are identical.  The same thing could be said about the T-47A.  The T-412 would begin to get problematic if you were working on the channel switching circuitry, but even that could be for most purposes serviced by an earlier manual.

Now I'll bow out to the real AN/ART-13 experts on the list.

73,
Mike / KK5F