WW II AM Sets
DH4PY

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      MC-619
  SCR-511/BC-745
      SCR-593/BC-728

 

 

 

 

 

 

  BC-745

is the transceiver of radio set SCR-511. It was developed for the Cavalry, when the cavalry already became obsolete.
The original name was Guideon Radio, but it was widely known as
"Pogo Stick".
A horseman with a Pogo Stick looks like a horseman with a banner in his hand.
The engineers wanted to have a widespread use. There is a mounting für mobile use and an external Power supply with NF- Amplifier.
Pogo was developed almost simultaneously to BC-611 , but is technically more advanced.

BC-745 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)

 
You may also read the article by Alan Tasker :
"U.S. Military Portable Radios"
Comparison BC-745 / BC-611:
  • Frequencies are changed by simply changing a module- the BC-745 is completely tuned then. ( Try this procedure with a BC-611 ...)
  • Antenna is much longer , i.e. much better for Short Wave.
  • Output power is 0.75 W , higher than BC-611's 0.38 W. = 1/2 s unit more than BC-611 (Thanks to Brooke, N6GCE, for this info).
  • But the BC-611 is more handy because it is only one component.
    SCR-511: Items in the museum:

    BC-745: , Transceiver with 9 tubes.

    BC-746 : Tuning unit with transmit and receive crystal. The bottom of BC-745 is twisted off ,BC-746 is replaced by an other BC-746.

    CH-39 : Chest unit ( *Ultra rare* !!) Contains dry battery BA-49, when on horse or in the field, and a second tuning unit BC-746.

    PE-157 : vibrator supply/audio amplifier as an additional way to power the BC-745, and as a way to have speaker type volume.: Is operated by:

    BB-54 : 2V- battery

    Close relationship BC-611 and BC-745:

    "BC-611" and "BC-745" (Pogo-Stick) have almost the same schematics. The resonant circuits even are made of the same components. The reason is that both radios were developed by the same producer: the company "GALVIN" .
      Resonant circles BC-611 / BC-745

    Frequency range:
    2 ... 6 MHz

     

    Technical data:
    HF output:
    750 mW
    Channels:
    1, crystal controlled
    Powered by:
    In chest unit dry battery BA-49
    In power supply battery BB-54
    Voltages:
    Heating 1.5 V
    Receiving 67 V
    Transmitting 120 V
    Modulation:
    AM
    Tubes:
    1 x 1S5
    3 x 1T4
    5 x 3S4