[Milsurplus] ARC-38 Control Head...NOT

[Mike Morrow]

>Someone was looking for an ARC-38 control head:
>
>120178817700

The description in the auction write-up is *very* incorrect.  This item is not part of a USN AN/ARC-38.  It is part of a simpler USAF 618S-1.

It is a 614C-2 channel-selector control head for the Collins 618S-1 144-channel crystal-controlled AM/CW 2 to 25 MHz system.  The RT-311/ARC-38 is similar to the 618S-1, except that frequency control is performed by a mechanically and electrically complex servo-positioned "stabilized master oscillator" system that tunes the set in 0.5 or 1.0 kHz increments on frequencies selected on its similarly complex C-1398/ARC-38 control head.  The 614C-2 and the C-1398 are grossly different devices, as are the frequency control sections of the 618S-1 and the RT-311/ARC-38.

The AN/ARC-38, usually installed with the AN/ARR-41, was the US Navy's replacement for their AN/ARC-25 (JAN designation for the combo of the AN/ARR-15 with the AN/ART-13).  During the same 1950s era that the USN bought the AN/ARC-38, the USAF bought a large number of commercial model 618S-1 systems without, AFAIK, any official JAN nomenclature assignment.  Military-purchased 618S-1 components have USAF contract numbers, as does the 614C-2 control head that is on auction.

Mike / KK5F