pk87.4

                            \/ Cut this track  
                |         O      o| 4           Top side of board
             28 |o        :   ____|
                |         :  /  _o| 5 
     U 5     27 |o        : /  /  |     U14
     (8530A)    |_________:/   | o| 6  (7910)
             26 |o       +-+   |  |
                |        ! !   | o| 7
             25 |o       ! !    \_|                     FIG 3
                         R 12

On the underside of the board link pin 24 of U14 (7910) to pin 9 of U 12
(4040). This puts 4.9152 MHz divided by 2 to the modem chip so it remains at
2.4575 MHz while the rest runs at twice the speed.

      If you have not made the modifications needed on the old PK-87 to the
audio output make then now. They are to turn C 24 round so the positive is
to the RADIO connector and if a TL082C is used as the opamp, to put in
series with the audio output from it to the RADIO connector, a 100 ohm
resistor to stop spurious signals appearing on the microphone line.
CONTINUED IN FILE PK87.10