[Hallicrafters] Help With Antenna Connector for RBK-16 (SX-36A)

[Michael Melland, W9WIS]

I picked up a great old (1952) Navy RBK-16 VHF receiver (Hallicrafters
SX-36A).  What in the world was the antenna connector they used ?  Looks
like it was a "plug" that the coax was attached to that one plugged into the
antenna socket inside the radio on the RF box.  Any help appreciated...
maybe one O' you old swabbies might even have one they'd sell ?

The manual lists:

PL-3, Type CN-49121A Antenna Plug, Navy Stock Number N17-C-71120-4869

Connector, Plug: 1 round female contact; straight type; over-all 2-7/8" long
by 13/16 " diameter; RF connector; cylindrical body; brass; nickle plated;
bakelite insert; 13/32 max cable opening. Contractor Drawing and part number
10A134

Mike, W9WIS