[Milsurplus] Major AN/ART-13 Variants

[Mike Morrow]

Dave wrote:

>Someone here is an expert on the variations of equipment
>commonly called "ART-13."  Would that person or persons
>kindly take a moment to comment on those variants and
>their deployment?

Until that expert writes, I'll summarize what I've learned *to be generally true* from decades of examining every unit I could, and reading all manuals I could find.

-------------------------------
USN UNITS:

ATC or ATC-1  (COL-52286) - Original model, US Navy pre-JAN nomenclature.  May have the early 8Q-1 MCW/CFI unit.  No transmitter top lid dynamotor control power interlock switch.  No vernier scale above HF VFO dial B.   May have old style mounting rails without shock absorbers, similar to those on the GP-7 or ATD.  Calibration book provides setting data at 5 kc intervals in 2 to 8 mc range, and at 10 kc intervals from 8 to 18.1 mc.  Calibration book is serialized to the transmitter, though all are identical.  Used with COL-23333 dynamotor.  LF oscillator covers 200 to 1500 kc in six bands, requiring COL-47281 and COL-47282 LF external tank coils.  Often paired up with the ARB receiver.

AN/ART-13 (T-47/ART-13) - Many (but not all) T-47 units were ATC units re-tagged or even just spray painted with "T-47/ART-13."  May have the later 8Q-2 MCW-CFI unit.  No transmitter top lid dynamotor control power interlock switch.  No vernier scale above HF VFO dial B.   May have old style mounting rails without shock absorbers similar to those on the GP-7 or ATD, now known as MT-161/ART-13, but the later MT-283 and MT-284/ART-13 shock mount system is more likely.  Calibration book provides setting data at 5 kc intervals in 2 to 8 mc range, and at 10 kc intervals from 8 to 18.1 mc.  Calibration book is serialized to the transmitter, though all are identical.  Used with DY-11 or DY-12/ART-13 dynamotor.  LF oscillator is now known as O-16/ART-13 and covers 200 to 1500 kc in six bands, requiring CU-25/ART-13 and CU-26/ART-13 LF external tank coils.  Often paired up with the ARB receiver.
When combined with the R-105(*)/ARR-15 receiver, this becomes the AN/ARC-25.

In these USN systems, the LF/MF external tank coil (CU-25 or CU-26) and the antenna attached to it are used only during transmit.  On receive, the receiver is connected to whatever antenna is attached to the transmitter's MF/HF antenna post.  Thus, two antennas are required for LF/MF transmit-receive operation.  This problem could be eliminated by the use of the SA-22/ART-13 antenna switching unit.

-----------------------------------
USAAF UNITS:

AN/ART-13A (T-47A/ART-13) - Should have the later 8Q-2 MCW-CFI unit.  Has transmitter top lid dynamotor control power interlock switch.  Has vernier scale above HF VFO dial B.   Uses the later MT-283 and MT-284/ART-13 shock mount system.  Calibration book provides setting data at 1 kc intervals throughout tuning range, due to the better setting precision allowed by the vernier scale above HF VFO dial B.  Calibration book is not serialized to the transmitter, all are identical.  Cal book is usually attached to transmitter with short chain.  Used with DY-17 or DY-17A/ART-13A dynamotor.  LF oscillator is the O-17/ART-13A and covers 200 to 600 kc in three bands, requiring CU-32/ART-13A LF external tank coil and antenna switching unit, which fills the roll of the USN's C-25/ART-13 and SA-22/ART-13 all in one box (as big as the transmitter!).  When combined with the BC-348-* (AN/ARR-11), this system becomes the AN/ARC-8.

AN/ART-13B (Early version - T-47A/ART-13 with CDA-T) -  This is identical to AN/ART-13A, except that (non-trival) modifications have been made to the T-47A for the installation of crystal oscillator assembly CDA-T in place of the O-17/ART-13.  The CDA-T allows for 10 crystal-controlled channels in the 2 to 18.1 mc range in bank A, another 10 such channels in bank B, and four crystal-controlled channels in the 200 to 600 kc range.  The remote control box C-87 is modified to allow selecting between bank A or B, and when the LF channel is selected, operation takes place on the LF/MF channel selected on the CDA-T.  For any channel, bank A and bank B frequencies must be within three percent.

AN/ART-13B (Final version - T-412/ART-13B) - This is identical to the AN/ART-13B early version, except that a switch (S117, LOW FREQUENCY EXTENDED RANGE mis-named!) has been added to front of the transmitter, below and to the left of the instruction plate.  This switch adds C151 to the tank circuit of the first multiplier stage V-102 to allow for MF operation below the normal lower limit of 2 mc.  When in the EXTENDED position, operation down to 1670 kc is possible.  Many T-412 units appear to have been made from old USN ATC or T-47 units, with a crude plate bearing "T-412/ART-13B" applied over the original name plate.  All these old USN units that I've ever seen (except one) had been fully upgraded to the T-47A configuration before or as part of making the T-412 version.

-------------------------------
So, when one is trying to create a system using an AN/ART-13, the components to be employed vary significantly depending on if it is a USN or a USAAF system to be created.  A R-105/ARR-15 would be inappropriate with a AN/ART-13A or -13B.  An O-16 or DY-12 would be inappropriate with a T-47A, etc.

Mike / KK5F