[Milsurplus] ART-13 question

[Mike Morrow]

Bill wrote:

>I have an ART-13 that I'm rebuilding to original and have several
>questions for the experts. The "test" switch on my unit has been
>replaced with a SPST toggle, but I think it should be a SPST
>momentary toggle

Yes, it's a spring-loaded normally-open toggle switch that closes to
ground the keying line when depressed.

>There is a number stamped into the upper right rear corner of
>the chassis that I think might be a serial number, but it doesn't
>match >the number on the identification plate on the right side of
>the transmitter. Do these units have two matching serial numbers?

The only number that matters is the one on the nomenclature plate.
I don't know what that number stamped on the chassis is supposed
to be.

>Also I'm looking for a calibration book, I know that I'm not going
>to find the one that belongs with this transmitter but would like
>to find one "for looks".

The AN/ART-13 is not like a BC-221 frequency meter with a unique
calibration book for each individual unit.  All the cal book data
are identical, regardless of the unit being an 17H-2, ATC, ATC-1,
T-47/ART-13, TCZ, or TCZ-1.  The only variation in the data between
cal books for these USN units results from the transmitter having
either the early 8Q-1 CFI unit or the final 8Q-2 CFI unit.  Any of
these models could have either of the CFI units.  There are different
calibration points shown in the cal book depending on which CFI is
installed.  The 8Q-1 used two tubes, and the 8Q-2 uses three tubes.

The USAAF's T-47A/ART-13, however, has a vernier scale above BFO
dial B which allows more precision in VFO dial adjustment.  The
cal book for a T-47A will be nearly three times the thickness of
the cal book for the USN units, because it contains data at 1 kHz
intervals.  Any T-47A should have the 8Q-2 CFI unit installed.

>My unit is a T-47/ART-13 USN model, it doesn't "say" ATC, but
>with all the anchors stamped inside it's a dead give away!

The ATC and the T-47/ART-13 are both USN transmitters.  The USAAF
used the T-47/ART-13 in early installations, but quickly settled
on the improved T-47A/ART-13, which the USN did not use.  It does
not sound like you have a USAAF T-47A, so there should be anchors
in abundance on your USN unit even though it is not an ATC.  (Of
course, many ATCs were "converted" to the T-47 simply by stenciling
"T-47/ART-13" in yellow paint somewhere on the case.)

You need a cal book that says "AN/ART-13" on the cover and that
matches the CFI unit installed in your T-47.  Most likely, but
not certainly, it will be the 8Q-2.

The best place to find these, IMHO, is on ebay.  But regardless of
model, the cal books are far harder to find than are the transmitters
themselves.

Good luck with your restoration.  With what receiver will you pair it?
The USN never did come up with anything better than the ARB or RAX-1
during WWII.  After the war, the AN/ARR-15 was the intended mate.  The
AN/ART-13 with the AN/ARR-15 makes up part of the combo known as the
AN/ARC-25.

Mike / KK5F