[Milsurplus] ARN-6 vs. 7

[Mike Morrow]

>I may be wanting to change out the ARC-55 for the pressurized ARC-27
>and just to keep everything in the same era may dump the ARC-73 with
>all its cables and head for a ARC-3 set up.

Hi Ray,

The AN/ARC-55 and AN/ARC-27 are in excess of 99 percent electrically identical.
I like the -55 better.  You can remove the top covers and watch the tuning
works operating, and see the tubes glow.  You can't do that with the -27.
You could even get a -55B model, with a solid-state power supply in place of
the dynamotor.

I'd bet that in the early 1960s there were many USAF/USA aircraft that carried
a combo of the -27/-55 for UHF and the -73 for VHF.  The -73 is fun to watch tune 
too.  About the only thing that would be a little out of place is the USN
AN/ARC-38.  The appropriate USAF HF set would be the AN/ARC-21 (AM) or AN/ARC-65
(USB) 140 pound, 18-inch diameter pressurized drum sets.  Those would be a
*really hard* challenge to find and operate today.  Plus, you'd need the
AN/ARR-36 auxiliary receiver, and for old-times sake, the AN/APN-70 LORAN A
set that was usually installed.

The AN/ARC-3 (or -36 or -49) is USAF.  I doubt there was any USN use unless
it was in an aircraft that had earlier been USAF or Army.

If you were going for USN gear only, the Navy started the shift to UHF-AM
command sets with the AN/ARC-12, and appears to have dropped interest in
VHF-AM command sets after the AN/ARC-1.  Installed AN/ARC-1 sets were converted
to the AN/ARC-12 simply by removing the RT-18/ARC-1 from the rack, sliding
in the RT-58/ARC-12, and changing the antenna from VHF to UHF.

The Air Force and Army continued installing VHF-AM sets along with UHF-AM
sets even after the AN/ARC-3, -36, -49 system.  That was followed by the
AN/ARC-73, AN/ARC-134, and AN/ARC-115, which were all early to late Vietnam
war era sets.

FYI, if you ever wanted to re-create a Vietnam-era Army aircraft radio set-up,
the amount of gear found in a late war commander's UH-1D/H Huey is interesting:

AN/ARC-51BX    UHF-AM Command Set (225 - 400 MHz)
AN/ARC-102     MF/HF SSB Set (2 - 30 MHz) (Collins 618T) 
AN/ARC-131     Low Band Tactical VHF-FM (30 - 76 MHz)
AN/ARC-134     VHF-AM Command Set (118 - 150 MHz)
AN/ARN-82      VOR Navigation (108 - 118 MHz)
AN/ARN-83      LF/MF ADF (0.1 - 1.75 MHz)
AN/APX-72      IFF Transponder.

All that gear covers quite a large portion of the radio spectrum.  There was
also an A.R.C. Type 12 emergency VHF transmitter.  No TACAN gear, though.

The "run-of-the-mill" UH-1D/H would be the same, minus the AN/ARC-102 HF set.

Mike / KK5F