Frequency Hopping Radios
DH4PY

Click picture to enlarge

 

 

 

      SEM-70
  SEM-90
      PRC-1088

 

 

 

 

 

 

  SEM-90 ( SEM-80):

is a modern mobile radio. Frequencies are set by

  • "Handwahl (HW)" hand, using fixed frequencies ; or by
  • "automatischer Kanalwahl (AKW)" , scanning frequency bundles.

    AKW is no real "Frequency Hopping" .Since the radio scans preset frequencies, I also list it in this category.
     

  • The radio set without the LV-90 is called SEM-80.
    Parts of the radio set:

    Main block A/VHF , consisting in

  • Main block A/VHF and
  • "automatischer Kanalwähler FSP 70" the automatic frequency changer.
    (The main block is part of SEM 70 / 80 / 90.)
    FSP 70 has 10 memories, each serving 16 channel bundles.
    The main block cannot be used standing alone.

    Frame FT 80 with built- in

  • 1-Watt-NF-Amplifier
  • HF-set
  • Power supply

    Booster LV 90

  • amplifying the main block, providing 40 W Hf.
  • ( without the LV-90 the radio set is called SEM-80.

    Mounting GP-80:

  • SEM-90 does not work without GP-80. GP-80, however is no part of radio set SEM 90.

    Mounting GP-80 and radio set SEM-90

    SEM-90 Relais set

    Freqency range:
    30.000 ... 79.975 MHz

     

    Technical data:
    HF output:
    low: 4 Watt
    high: 40 Watt
    Powered by:
    car battery
    Channel spacing:
    25 kHz
    Modulation:
    Frequencies set by hand: FM
    Automatic frequency setting : digital, delta modulation
    Data transmission:
    up to 16 kBit
    Antennas:
    car antenna FA 80 or
    fixed antenna STA 80
    Range:
    depending on antenna or output: 9 ... 30 km.
    Hints:
    The mounting GP 80 is needed for vehicular use. However, it is not part of the set SEM 80 or SEM 90.