[ARC5] Why is the ARC-5 Tx rack so hard to find?

[Mike Morrow]

Dave wrote:

> ...in actual deployments the expensive-if-you-can-find-it
> C-30A was rarely used.

That's true if there was ONLY ONE transmitter in the AN/ARC-5 installation.  That would not have been typical except in USN trainer aircraft

I have a manual describing such a system in a trainer.  There was a:

T-19/ARC-5 for 3105 kHz (or similar), plane-to-plane and plane-to-ground.
R-23*/ARC-5 tunable with C-125/ARC-5 for 278 kHz (or similar), ground+to+plane and directional (Adcock) beacons.
R-26/ARC-5 tunable with C-125/ARC-5, usually set to T-19 grequency.

The photos I have show a BC-442-A antenna relay instead of the RE-2/ARC-5.  I guess sometimes a "make do" item had to be used.

The only transitter-related pilot controls were a RADIO/ICS selector and the PTT switches.

> The set was hard-wired to Phone mode and the pilot
> interfaced via a J-16 or J-22 junction box with a stick
> or wheel mounted PTT switch.

The AN/ARC-5 receiver control boxes except C-26 likewise are wired for VOICE operation only.

AFAIK, the transmitter control box was always used in all ATA and SCR-274-N installations, and all multi-transmitter AN/ARC-5 installations.  

So, the selection was:

None   For single-transmitter MF/HF-only.
C-29   For MF/HF-only.  It is unlikely many such non-VHF installations existed.
C-30   For MF/HF/VHF, MF/HF-only, or VHF-only.  It was large, mechanically-complex, and no-doubt expensive.  Soon dropped in favor of  C-30A.
C-30A  For MF/HF/VHF, MF/HF-only, or VHF-only.  Same size, weight, and simplicity of C-29.  Unlike C-30, it allows selecting VHF receiver channel without turning on transmitters.

Mike / KK5F