pk87.3

On the underside of the board link the through hole on the track that
has just be cut to pin 11 of U 20, see Fig 2.

            ____________             Bottom side of board
            _________   \            at top end of U 5 (8530A)
                     \   o
 Connect -> =====\    o         /=
 this hole  ==O  \==============/
 to pin 11         ___________
 of U 20    ______/ _________ \___
            _______/ _______ \____
            ________/ ___   \_____                      FIG 2
            _________/ o \
                       Pin 1 U 5, 8530A
      A small change on the PK-88 compared to the PK-87 is that pin 1 of
U14 (7910) is taken to Vcc, this is done by linking  pin 1 and pin 2 of U14.

      If the PK-87 has a 4.9152 MHz crystal put in the new EPROM and
replace the board in the cabinet. Apply power and the unit should enter
the auto baud routine  and the unit can be started as from cold.
If all is satisfactory turn the link block on JP 1 so it links the pins,
remove power and reassemble the cabinet. (If the clock runs very fast and
the timings are odd you have the wrong! version of the EPROM where the
clock interrupt rate needs halving. You can either get a different EPROM
or put in a 74HCT4020 and do the modification as per the NOTE at begining.
CONTINUED IN FILE PK87.7