[ARC5] Aircraft Radio Corporation airband oddities

[zakariya.abu at yandex.com]

Hello Colleagues,

I was suggested to join this group when I learned that there are many 
experts in aviation radios present. I got interested in the Aircraft 
Radio Corporation's Type 12 series and the derivatives, and discussed 
the R-22 on two different forums lately.

Now, I'd like to ask some questions related to the Aircraft Radio 
Corporation "Combined Sets", which are related to the AN/ARC-60. I 
discovered lately that this company made peculiar sets consisting of 
various parts for the military and government use, which seem not to 
bear the unique nomenclature.

(1) The first one was an emergency backup transmitter using the Aircraft 
Radio Corp. C-4209/ARC or the Aircraft Radio Corp. C-80B control unit, 
and the Aircraft Radio Corp. T-366 transmitter, which was the military 
version of Aircraft Radio Corp. T-11A/B. It allowed five Tx presets. 
This set was used on the early UH-1 Hueys (models ABCD and F), CH-47A 
Chinook, and CH-54 Tarhe when the primary VHF AM comm radio 
malfunctioned. When combined with the Aircraft Radio Corp. AN/ARN-30 VOR 
or the AN/ARN-82 VOR used as a VHF AM receiver, the set could operate as 
a full-fledged VHF AM comm radio, albeit on relatively limited number of 
channels.
The transmitter part consisted of the following items:
     Transmitter, Radio T-366A/ARC
     Mount MT-1142/ARC
     Dynamotor DY-86/ARN-30
     Filter, Direct Current Power R-726/AR
     Relay, Switch RE-275/AR (ARC Type K-18)
     Sidetone Relay K-12 (MS24139-5)
     Switch Panel, P/N 204-075-709
     Control Panel P/N 204-075-708 (C-4209/ARC)  eg. on UH-1A/B
     Control Panel (ARC Type C-80B)    eg. on UH-1C/E/F
The link below shows the C-4209/ARC control unit:
https://www.worthpoint.com/worthopedia/aircraft-radio-corp-4209-arc-2941224344

(2) An Aircraft Radio Corp. VHF AM comm set from ca. 1962, which used 
the C-100A control head, the R-38A receiver and the T-25C transmitter. 
It was used primarily on light and trainer aircraft worldwide. The T-25A 
could operate on 310 channels in the VHF airband. Actually, very little 
is available on these radios. The control unit most likely looked like 
the one from the link below:
https://digitaltmuseum.se/021029692309/manoverapparat

(3) A relatively similar setup involved the ARC Type 15G VHF NAV set and 
its R-35A VOR receiver, and the ARC Type C-109A control unit which could 
control a T-25C transmitter, as well, to produce together a backup COM 
radio.

(4) A backup VHF COM radio consisting of the Aircraft Radio Corp. Type 
15E (AN/ARN-30A or B???) VHF NAV receiver by Aircraft Radio Corp. Type 
R-32A with the C-1254A or C-2345 control units, which tuning crank 
sported the "Press to whistle" function to tune the Rx frequency to the 
crystal-controlled frequency of a transmitter from the Aircraft Radio 
Corp. inventory, albeit of unspecified nomenclature. I guess it might be 
the above mentioned T-25. The control unit dial covered the full 108-136 
VHF VOR and COM band.
The C-2345 control unit can be viewed here:
https://www.worthpoint.com/worthopedia/arc-2345-arn-control-receiver-vhf-nav-1993443937

Did each of these sets have any single name or short nomenclature 
(except the NSN) that would denote their TRx character? Or were they 
rather the variations of the Aircraft Radio Corp. modular products? More 
information on the setups # (2), # (3) and # (4), and their parts would 
be welcome, particularly if originating from the mfg. literature.

Best regards,

Jan SP5XZG