[Milsurplus] ARR-2

[Mike Morrow]

>Don't think anyone sed BC-946 bcb command rx was the tunable if
>for the ZB 234-258 trf set.  In fact it came with an 'old cannon' power
>take-off for a ZB (or ARR-1).

The ZB-series more commonly was matched up with the RU-series receivers.  The mounting hardware on the bottom of the ZB was exactly the same size as the RU tube cover, so the ZB could mount there on top of the RU in place of the RU tube cover.  But pictures of SBD and other period USN aircraft that I've seen with the ZB/RU installation all have the ZB mounted away from the RU.  I'd bet few if any BCB "command sets" ever got attached to a ZB or AN/ARR-1.

The the top of the ARB receiver case also has latch pins for direct mounting the ZB, and an accessory power connector on the front.

Doubtless, the .52 to 1.5 mc ARA and the R-24/ARC-5 receivers had supporting the ZB as ONE of their purposes, but another less commonly discussed function of all these receivers was to serve as the LF/MF localizer receiver for  the USN's abortive Air Track ILS, the ZA, ZAX, and AN/ARN-9.  The R-23 and and R-24 had a special audio output that could be connected, through a special front panel adapter/relay-audio box MX-19/ARC-5, to provide the proper inputs to the Air Track system.  I believe that the AN/ARN-9 was the ILS system that the MX-19 was actually designed for.

With respect to the A.R.C. Type 12 series BCB receiver, the R-10A, it was definitely NEVER part of the ZB, AN/ARR-1, or AN/ARR-2 systems.  The ZB/YG/ARR-2 system requires that the BCB receiver have a BFO for the NAV function.  The post-war Type 12 LF/MF receivers have NO BFO.  The R-10A is technically incapable and way out of place in time to have supported ZB/YG type homing functions.

While talking about the A.R.C. Type 12 system, we should avoid the common but seriously wrong error of referring to this as the "ARC-12."  That causes confusion with the real AN/ARC-12, of which the main unit is the RT-58/ARC-12.  It is a ten-channel early USN UHF-AM set that can directly plug-in in place of the RT-18/ARC-1 VHF-AM set, with only a modification to the antenna system being required.  So, the A.R.C. Type 12 is definitely NOT an AN/ARC-12!

Mike / KK5F