High Band GE Custom MVP (Exec II) 222 Mhz Conversion

High-band GE MVP/EXECII Exciter on 220 Mhz
(19D423293G2)
Rev. C
1 April 1990

Procedure:

  1. Remove the cans from T105, T106, T107 and T108.
  2. Remove the T107 and T108 coils.
  3. Remove T105 and T106 coils and install them in the T107 and T108 locations.
  4. Remove all but 3 1/2 turns from the T107 and T108 coils and install them in the T105 and T106 positions.
  5. Remove R134 and L107. R134 may already be missing.
  6. Replace R130 with a jumper.
  7. Replace the following with the new values shown:

    1. C138 - 6.2pf
    2. C139 - 5.1pf
    3. C141 - 3.9pf
    4. C146 - 13pf
    5. C147 - 6.8pf
    6. C149 - 22pf
    7. R101 - 100 1/4 watt
    8. R126 - 470 1/4 watt

  8. Install a 1.8K 1/4 watt resistor, from the base of Q108 to the intersection of L108 and C144, on the bottom of the board.
  9. Reinstall the coil cans.

    Notes:

    1. The last doubler, Q107, is now a tripler.
    2. The new crystal formula is: xtal = f/18. Calculate the fundamental frequency and put it back into the original crystal formula. Order the equivalent high-band frequency.

    High-band GE MVP/EXECII Receiver on 220 Mhz
    (150-174 MHZ)
    REVC
    1 April 1990

    Oscillator Multiplier Board (19D423241G1):
    1. Install a 12pf capacitor in the space reserved for C412.
    2. Install a jumper between the bottom two turns of L403 closest to the position reserved for C417.
    3. Install a jumper from the center of L403 to the next turn, closest to R413.

    High Band Adapter Board (19B227258):

    1. Remove C460.

    Mixer Board (19C320153):

    1. Install a jumper from the center of L502 to the first turn of the inductor going towards C504.
    2. Install a jumper from the bottom center turn of L502 (closest to the gate of Q501) to the ground plane to the right of L502 and below C502.

    RF Assembly (19D416693):

    1. Remove the helical resonators:

      L301/311, L302/L312, L303/313, L304/314, L305/315, L306/L316 and L307/L317.

      Remove 1 3/4 turns from the cold end of each resonator and reinstall. A soldering iron in the few hundred watt range is required to complete the procedure.