The comparative rarity of the Navy ATB transmitter has absolutely nothing on the difficulty in finding its peripherals. Weary of searching for the shock mounts, it became clear that the only practical solution was to fabricate a pair using original drawings and materials. Seen above is a partially finished first prototype of that effort - the 12" dial calipers are for scale. The small stainless steel button gets riveted to the topside tab (not visible), and slides into a mating hole in the rear of the transmitter. Normally the pair of these mounts was then installed on crossbeams on a larger rack in the aircraft. A couple of nomenclature tags was to be next in the fabrication queue.
Below are photos of an original mount I was eventually able to acquire. This is a phenomenon that others have experienced as well...it seems that only after sinking inordinate amounts of time into fabrication that an original part floats to the marketplace surface...heh. Mounting holes in the sheet metal for the front snap slide pin and nomenclature tags are symmetrical so that it could be used on either side of the transmitter. Only the tag was then made unique for left and right sides...go figure...
Both the ATB transmitter mount and the ARB receiver mount are about as complex a fabrication project as one can
imagine for devices that simply hold a radio up in the air on shocks. One has to
wonder what RCA was thinking when they designed them! They are difficult to install in the aircraft, and require
extremely careful alignment of far too many holes in a rack or the radios won't fit into them without force. They are
obviously expensive to manufacture because of all the piece parts that go into them. The complaint list goes on and on.
For those with a lot of patience in fabrication, here is a sketch of the mount, including piece parts.