Modern Era FM Handheld Portables
DH4PY

Click picture to enlarge

 

 

 

      PRC-614
  PRC-68
      PRC-68 B

 

 

 

 

 

  RT1113/PRC-68

is a "Squad-Radio", a radio operated with one hand for short range communication. Older examples for Squad radios are SCR-536/BC-611 (AM) from WWII or PRC-6 (FM).
The demand for a modern Squad Radio resulted in the development of the synthesized PRC-68, becoming the "father" of radios to follow:
PRC-68A, PRC-68B, PRC-126, PRC-128, and PRC-136.


PRC-68 is a "Squad Radio", a small hand held unit for very local communications. The collection shows all American Squad radios from their beginning (1941) to 1986.

MAB
(1941)

DAV
(1941)

SCR-511/ BC-745
(1941)

SCR-536/ BC-611
(1942)

RT-196/ PRC-6
(1950)

(PRC-34/ PRC-36)
(1961)

PRR-9/ PRT-4
(1965)

RT-1113/ PRC-68, A,B
(1976/84)

RT-1547/ PRC-126
(1986)


A replacement for PRC-6 was needed. Most of the experimental radios were either too heavy, lacked performance or were too expensive.
The last attempt of the Army were two separate radios:
Two-channel transmitter AN/PRT-4 and one-channel receiver AN/PRR-9.
 
In the mean time, the Marine Corps no longer wanted to wait for response of the Army to have a joint development of a multi- channel transceiver. They combined PRR-9 and PRT-4 in a single case and called it
AN/PRC-88.
 
In the same time frame the Marine Corps started the development of a totally new type of Squad Radio. The development lasted from 1964 to 1976.

In the competition for the PRC-68, prototypes were supplied from Magnavox/Ft. Wayne (now Raytheon) and from Motorola. Magnavox won.

   ==> Motorola's prototype is shown here <==
Then RT-1113/PRC-68 was built by Magnavox / Indiana.
 
Restrictions of PRC-68:
  • 50 kHz channel spacing instead of the emerging new standard of 25-kHz.
  • You need a field strengh meter to tune the antenna-matching network    (module 1A5) when changing channel sets.
  • The 10 channels are in successive steps of 200 kHz spacing.
     
    You may find a very detailed history of this radio in the article:
    "U.S. Military Portable Radios" by Alan Tasker, WA1NYR
     
    Quoted from the article by Alan Tasker:
    "The AN/PRC-68 Legacy" by Alan Tasker, WA1NYR.

    Frequency range:
    30 ... 79.95 MHz

     


    Technical Data:
    Memory Channels:
    10, 200- kHz apart.
    Channel spacing:
    50 kHz
    Channels:
    1000
    HF Output:
    1 W
    Modulation:
    FM
    Frequency departure:
    +/- 0.005 %
    Range:
    3 ... 5 km
    Modules: 8
    1A2, IF/AF
    1A3, FILTER/IF
    1A4, Tx PA
    1A5, ANTENNA COUPLER
    1A6, CONVERTER
    1A7, VCO
    1A8, MODULATOR/MIXER
    1A9, SYNTHESIZER
    Antennas:
    short or long rubber antenna, tape antenna
    Powered by:
    15V ( several kinds of batteries or cells )
    Squelch:
    TX: 150 Hz, RX: carrier
    Measurements and weight:
    212 x 96 x 38.6 mm, 1.3 kg (without Handset)
    Sensitivity:
    0.5 ÁV / 10 dB
    NF- Output:
    20 mW
    Produced from:
    1976