[ARC5] C-43/ARC-5

[Mike Morrow]

Jay wrote:

>The subject is currently up for auction on the usuall block.It is made 
>by Western Electric and has SCR-274N dials yet bares the nomenclature 
>of an AN/ARC-5 component.

Western Electric developed and manufactured the VHF command set for the
SCR-274-N, but it was not accepted by the Army beyond the evaluation level.
The Navy accepted the design with some modifications, especially in the
transmitter modulator design.  The modified BC-950 VHF transmitter became 
the T-23/ARC-5.  The BC-942 VHF receiver became the R-28/ARC-5, and the
BC-938 control box became the C-43/ARC-5.

It is thus no surprise that W.E. VHF plus MF/HF control boxes like the
C-43/ARC-5 have W.E. SCR-274-N style dials.  They may even have been
originally made as BC-938s.  Only W.E. made the AN/ARC-5 VHF components,
though A.R.C. made some auxillary items (like mounting racks) under the
same order number as W.E. made their VHF AN/ARC-5 gear.

It appears that there was very little use of control boxes with tunable receiver
dials for most AN/ARC-5 installations.  Judging from documentation in manuals
and the frequency of which such equipment can be found, the C-38/ARC-5 was the
most common AN/ARC-5 receiver control box.  It has ONLY audio controls for the
VHF receiver (R-28) and a MF or HF receiver (most likely a R-26), plus full
controls for the R-4/ARR-2 VHF homing receiver.  The AN/ARC-5 communications
receiver in such installations was lock-tuned locally and had no remote tuning
capability.  The VHF channel in the R-28 was selected using the VHF transmitter
control box C-30A/ARC-5.

On the transmitter side, the C-30A/ARC-5 control box appears to have been the
most common control box.  This control box may be used in a VHF plus MF/HF
installation, or in MF/HF-only installation.  It made the same-sized MF/HF-only
C-29/ARC-5 superfluous, hence the C-29 is very rare for very good reason...it
wasn't used to any real extent!

The Army rejected the VHF SCR-274-N.  The C-43 is only for potential use in
Navy installations containing the VHF R-28.  The item in the auction thus presents
no evidence of common gear sharing between the services.  Even the Navy didn't
use controls like the C-43 to any extent, so these orphan components are almost
always found with no trace of having been used, just like the one on auction.

It's a little amuzing to see great sums expended to re-create a MF/HF AN/ARC-5
installation using three C-26 remote receiver controls and a C-29 transmitter
control box to control three tunable receivers (R-23, R-26, R-27) and two MF/HF
transmitters (akin to the standard SCR-274-N configuration), when installations
of that type were likely so rare in the AN/ARC-5 as to be virtually mythological.

Mike / KK5F