Modern Mobile FM Sets
DH4PY

Click picture to enlarge

 

 

 

      AN/VRC-53
  SEM 25
      EM-25

 

 

 

 

 

 

 

  SEM 25

is a vehicular radio of the German BW.

The radio set consists of two basic types: a transceiver (SEM 25) and a receiver (EM 25). This receiver is mostly identical to the transmitter.

SEM 25 replaces the transceivers: RT-66, RT-67, RT-68, RT-70 and the receivers R-108, R-109 and R-110. It can cooperate with all these radio sets, also  with PRC-6/6, PRC-8, PRC-9, PRC-10,
FSE 38/58 and SEM 35.

The operating device can be screwed to the front of the SEM 25, or mounted up to 10 meters apart.

The complete radio set also serves as communicator onboard, out of the vehicle and as remote control.

Only the transmitter part contains tubes- the rest is fully transistorized.
The transmitter tubes are: QQE03/12, 6111 and 5639.

To every SEM 25 or EM 25 belongs a 2.5 meter rod antenna and an antenna matcher (AGAT).
At every frequency change the SEM25 (EM 25) matches the antenna with the help of the AGAT automatically.
The AGAT is no ATU, the values it uses are fixed. That is why the AGAT can be trimmed manually, to match any vehicle or antenna type.

Frequency range:

26.0... 69.95 MHz

 


Technical data:

Mass + weights:
Radio with control device: 222 x 268 x 330 mm; 17 kg.
Baseplate 120 x 300 x 320 mm, 9.5 kg
Transmitting power
adjustabe  15 / 1 Watt, FM
Frequency departure
+ - 3.5 kHz.
Frequency selection:
switches, altogether 880 channels.
10 channels fixed programmable.
Sensitivity,
0.5 UV UV with signal-to-noise ratio of 20 dB
Call tone:
1500 cycles per second
Power supply:
24V battery or power supply unit, transmitting/receiving 7/1 A.
Museum's Accessories:
Antenna testing set, on-board speech testing set, Groundplane with antenna tuning; Remote control set; etc.
7-El.-directional antenna AYA 25/ft 17 in (very large!) box.

Radio jamming device for use with SEM-25:
ECM/FSS 209