Star Tech Journal

22
STAR*TECH JOURNAL/SEPTEMBER 1983
Service Tips continued.
Bally Baby Pac-Man Feature Lamp Burnout
Problem: Baby Pac-Man feature lamps burn out too soon, i.e. they
return coming from pins l and 3 of J 12 on the lamp/ solenoid driver
board shown in Figure 3.
Hints: 1. Mount heatsink with the rectifiers on the right side of the
game as you are looking into the back of it 2. Remember to tie both
wires from J12 together as well as the other sides. See Figure 4.
Thanks to Steve Renfrow, Rowe International, Denver, CO.
have a short life.
Cause: Switched illumination voltage too high.
Cure: Reduce voltage by approximately two volts by using two
heavily heatsinked bridge rectifiers rated at 25 amps each in series
with each other and in series with the switched illumination bus
FIGURE 3: AS-2518-107 LAMP/SOLENOID DRIVER
COMBINATION BOARD
I J12 (SWITCHED ILLUMINATION BUS RETURN)
D
N
.Q....-
D -:._
o. ••
D "'
D -
24
NOTI 1 - - - ¼ - ( ) ~,..,...,...,...,..,..,..,..,-,-,,..,..,....,...,..,..~...,..,..,..,..,..,...,..,..,
U3
00000000000000 000000000000000
I
......... 1,011 11111,11110111
Ji
I
21 , - - - - 1 - - - = - 1 - - + - - - - - ;
Uf
II
U2
FIGURE 4
TO SW ILL GND
,--- ------ - -
I
BOTH
WIRES
FROM
J12
-
-,
I
I
AC
AC
I
I
I
+i
I_
AC
AC
HEATSINK
I - - -· -- --• • - - - - - - J