[Milsurplus] Wanted

[Mike Morrow]

Larry wrote:

> I have a pair of the BC-496 dual receiver control box's.
> Neither has the small frequency dial scales.  Any extras around?
> The current one is being used with a BC-453 and a BC-454 so would
> like to find the frequency dials (small types) for those two
> radios.

In the SCR-274-N, control box dials weren't included with the control box.  In the ARA they usually were.  I've obtained a complete set of dials (see below) for all three sets, except for the BC-946-B.  I got most of them through ebay.

The early ARA and all the SCR-274-N remote dials have a large flat front disk with a narrow sharply-sloped outer rim on which the frequency scale is inscribed in small non-luminous characters and gradations.  Later ARA and all AN/ARC-5 remote dials have a smaller front flat surface disk surrounded by a much larger sloped rim with larger luminous characters and gradations...much easier for a pilot to read.

> Also have a BC-946B that it would be nice to have a small dial
> scale for as well.

The later ARA 6052 and ID-26/ARC-5 dials for the BCB receivers show up rarely.  But the narrow-rim small-character MC-415 remote dial for the BC-946-B is genuinely really rare.  I'vd never been able to find one.

The scale calibration is identical for the dials of all three systems, but I'd like to find someday a real MC-415 for a SCR-274-N (communications) plus AN/ARR-1 (vhf homing) system.  In that system, the BC-453B beacon receiver is removed from the rack and replaced by a BC-946-B being fed RF from a R-1/ARR-1 VHF "ZB" homing adapter.  The center section of the three-receiver control box BC-450-A that was controlling the BC-453-B now gets the MC-415 dial and controls the BC-946-B to demodulate the output of the R-1/ARR-1 ZB homing adapter.

> Any ARA control box's around? Have an ARA CBY-46104 1.5 to 3.0 mc
> receiver i'd like to try out.

The ARA CBY-23155 two-receiver remote control box is eletrically and mechanically identical to your SCR-274-N BC-496-A control box.

There is no two-receiver control box in the AN/ARC-5.  Two C-26/ARC-5 single-receiver control boxes would be needed for similar service use.

The entire SCR-274-N system is identical to the ARA/ATA system without the 1.5 to 3.0 MHz receiver and the 2.1 to 3.0 MHz transmitter, except for receiver and modulator sidetone AF impedance.  The ARA/ATA uses low impedance, while the SCR-274-N uses either high or high/low impedance.

> Same with AN ARC-5 R-24 and R-25.

The receivers of the AN/ARC-5 are improved versions of the ARA receivers that are backward compatible with both of the earlier systems.  Once you have a system set up to use your SCR-274-N receivers, you may mix and match any of your ARA and AN/ARC-5 receivers with your SCR-274-N receivers in your SCR-274-N racks.

"Command set" Receiver Remote Dial Nomenclatures:

Freq Range.     ARA.              SCR-274-N.    AN/ARC-5
.19 to .55.     ARC 6051.         MC-212.       ID-25/ARC-5
.52 to 1.5.     ARC 6052.         MC-415.       ID-26/ARC-5
1.5 to 3.0.     ARC 7575.         na.           ID-27/ARC-5
3.0 to 6.0.     ARC 6053.         MC-213.       ID-28/ARC-5
6.0 to 9.1.     ARC 6054.         MC-214.       ID-29/ARC-5

Typically, the A.R.C. part number (6051, 7575, etc.) is the only identification that appears on the back of these dials.

Two-Receiver.   ARA.              SCR-274-N.    AN/ARC-5
Control Box.    CBY-, CCT-23155.  BC-496-A.     na

Mike / KK5F