[ARC5] Other Aircraft Radios

[Mike Morrow]

Bob wrote:

>I remember the radios used by the USAF up to 1960. They were all channelized.

There were many different sets, but those listed below probably cover 90 percent
of the installations in the US Air Force and Army.  
 
USAF and USA, about 1960
HF -AM     AN/ARC-8   (AN/ARR-11 (BC-348) and AN/ART-13A, 0.2 to 0.6, 2 to 18.1 MHz)
   -AM     AN/ARC-21  (2 to 24 MHz, 0.5 kHz step, mechanical dig. freq. display)
   -USB    AN/ARC-65  (2 to 24 MHz, 0.5 kHz step, mechanical dig. freq. display, USB version
                       of AN/ARC-21)
   -U/LSB  AN/ARC-58  (2 to 30 MHz, 1 kHz step, mechanical dig. freq. display)
   -AM     AN/ARC-59  (2 to 18 MHz, 20 crystal-controlled channels, 18S-4)
   -AM     618S-1     (2 to 25 MHz, 144 crystal-controlled channels)
VHF-FM     AN/ARC-44  (24 to 52 MHz, 100 kHz steps, mech. dig. freq. display)
VHF-AM     AN/ARC-3, -36, 49 (8, 16, 48 crystal-controlled channels, 100 to 156 MHz)
UHF-AM     AN/ARC-27  (225 to 400 MHz, 0.1 MHz step, mechanical dig. freq. display,
                      control boxes typically stored 20 preset channels on drum)
           AN/ARC-55  (Unpressurized AN/ARC-27)
           Also, AN/ARC-33, AN/ARC-34.
ADF        AN/ARN-6   (0.1 to 1.75 MHz, analog freq. display) 
 
USAF and USA, about 1970
Earlier sets plus:
HF -L/USB  AN/ARC-94   (2 to 30 MHz, 1 kHz step, mech. dig. freq. display, 618T-2)
           AN/ARC-102  (2 to 30 MHz, 1 kHz step, mech. dig. freq. display, 618T-3)
VHF-FM     AN/ARC-54   (30 to 70 MHz, 50 kHz steps, mech. dig. freq. display)
           AN/ARC-131  (30 to 76 MHz, 50 kHz steps, mech. dig. freq. display)
           AN/ARC-114  (30 to 76 MHz, 50 kHz steps, mech. dig. freq. display)
VHF-AM     AN/ARC-73   (116 to 152 MHz, 50 kHz step, mech. dig. freq. display)
           AN/ARC-134  (116 to 150 MHz, 25 kHz steps, mech. dig. freq. display)
           AN/ARC-115  (116 to 150 MHz, 25 kHz steps, mech. dig. freq. display)
UHF-AM     AN/ARC-51BX (225 to 400 MHz 50 kHz step, mech. dig. freq display,
                        control boxes typically stored 20 present channels on drum)
           AN/ARC-116  (225 to 400 MHz, 50 kHz steps, mech. dig. freq. display)
ADF        AN/ARN-59   (0.1 to 1.75 MHz, analog freq. display)
           AN/ARN-83   (0.19 to 1.75 MHz, analog freq. display)

The term "command set" is popular on out lists with reference to a particular set
of radios, but later eras had command sets as or more frequently used as our old
favorite, the most frequently used models being:

Early 1950s:  AN/ARC-27    UHF-AM (and AN/ARC-55 variant)
Mid-1960s:    AN/ARC-51BX  UHF-AM (and other AN/ARC-51 variants)
Mid-1970s:    AN/ARC-164   UHF-AM (many different varieties)

The Collins AN/ARC-27 is, IMHO, one of the most technically and historically
significant aircraft radio sets of all times.  In the HF area, the Collins 618T-series
(AN/ARC-94, -102, and others) would be the best candidate for the most used HF
aircraft radio for the longest period of time.

>The civil aircraft radios prior to 1960 had analog tuning. I'd like to find photos
>of some.

In the light aircraft arena, the pattern had been established prior to WWII of
using an aircraft transmitter on 3105 (and sometimes 6210) kHz AM, and an aircraft
receiver on LF/MF (generic 278 kHz).  By the early 1950s, 3105 kHz ops shifted to 3023.5
kHz (which is still allocated to SAR service).   There are many different models that
still show up on ebay (GE AS-1B, Motorola AT-99-44, Bendix PAT-40/PAR-70, Air-Radio,
Harvey-Wells, RCA, Lear Radio, Hallicrafters CA-2,just to name a few.  Also in the late
1940s, early 1950s, the HF transmitter was replaced by VHF transmitter, retaining the
LF/MF receiver.  Then, both transmitter and receiver made it to VHF.  The early 1960s
King KX-150 is claimed by some to be the first light aircraft set whose frequency could
be directly dialed in (90 channels, 118 to 127 kHz, 100 kHz steps), but I'm not certain
of that.

A.R.C. of course made their post-war commercial VHF-AM gear, but that stuff had to
be pretty high-dollar gear that likely the US military was the main customer.  I
doubt many small private aircraft had commercial A.R.C. gear installed.  

Lloyd's website http://www.lloydsdipsydumpster.com/ has some pictures of sets like
this.

>Were radios ever built that used DIGISWITCHES for frequency control?

I'm not sure what that is.  Most military sets after the mid-1950s used direct-dialed
frequency input.  Eventually, sets for the private aircraft market did too (KX-150,
A.R.C. Model 210, etc.)

>I learned to fly in Cups and Champs with no radio. They did not have lights either!

When my dad got his private pilot's license on the WWII GI-bill, none of the aircraft
he flew had any radio.  But there were many models of dry-battery powered beacon band
receivers available in the late 1940s.  The Motorola Air-boy shows up on ebay often.
These simple receivers usually cost about $30 then (about $400 in 2011).  They
would have been a very useful device to have back then, when all those LF/MF diectional
A-N (Adcock) beacons were still in operation, and most of the towers on 278 kHz, and
a lot of airport and weather info was broadcast on the beacon.

Not really related to this, but interesting to me, is the radio suite on board the
typical Vietnam-era UH-1D/H "Huey" helicopter of 40 years ago:
AN/ARC-51BX UHF-AM (225-400 MHz)
AN/ARC-102  MF/HF  (  2- 30 MHz)  Command aircraft only
AN/ARC-131  VHF-FM ( 30- 76 MHz)
AN/ARC-134  VHF-AM (116-150 MHz)
AN/ARN-82   VOR    (108-127 MHz)
AN/ARN-83   ADF    (0.19-1.75 MHz)
AN/APX-72   IFF
(plus some emergency VHF and UHF gear)
That's a pretty impressive amount of RF spectrum that these aircraft were equipted
to cover, especially the command model with HF, for what is often considered to be
a common combat/utility aircraft. 

Mike / KK5F