16
"power board" (the power supply), an "interface
board" (the interface section), and a "hori-
zontal/vertical board" (for the deflection
circuitry). Still, there are a few parts on the
chassis, but most can be found on the board.
An Electrohome monitor has no separate boards,
except for the neck board, and just has a flat
chassis.
Another good way to determine which monitor
you have is to check the transistor call out
numbers that are printed on the chassis next to
the part. For instance, on the neck board, one
of the color output transistors is TR401 . If you
look through the schematics or the parts lists,
you will find TR401 in the Wells-Gardner
literature. On the other hand, the neck board
transistor may say Xl0l. Xl0l can be found
in the Electrohome literature. So, all Wells-
Gardner transistor call outs begin with TR, and
Electrohome transistor call outs start with an
"X".
STARHECH JOURNAL/AUGUST 1982
GO'l'l'LTEB
SYSTEM 80 CONTROLLED LAMP CKT TROUBLESHOOTING
The following flow charts are provided for ease of troubleshooting any
Gottlieb System 80 pin game. (The diamond shaped blocks denote
decision steps.)
Chart 1·
REPLACE
YES
PARTS INTERCHANGEABILITY
Some parts can be interchanged on all of the
monitors. Here are the rules:
REPLACE
PROM CHIP
NO
l. You CAN swap the voltage regulator TR502
or X0l on any Wells-Gardner or Electro-
home 19-inch monitor. You CAN NOT
swap the voltage regulator on the 13-inch
Wells-Gardner or Electrohome (G07-902)
since the Electrohome uses an integrated
circuit for the power supply.
JUMPER TRANSISTOR
COLLECTOR
TO GROUND
2. You CAN swap any resistor between moni-
tors that has the same resistance, wattage
rating, and tolerance.
CHECK TRANSISTOR
BASE FOR 1.4vdc
3. You CAN swap any capacitor between
monitors that has the same capacitance, and
voltage rating.
4. PICTURE TUBES:
Due to the fact that "ELECTROHOME"
is now (October, 1981) using a picture tube
with an internal shield, these picture tubes
can be used in EITHER "WELLS-
GARDNER" or "ELECTROHOME"
monitors.
However, a "WELLS-GARDNER"
picture tube can ONLY be used in a
"WELLS-GARDNER" monitor. It will
not function properly if installed in an
"ELECTROHOME" monitor. The picture
purity will be off.
5. You CAN NOT change any part that is a
safety part, one that is shaded in gray on the
schematic; it MUST be IDENTICAL to
the original. To do otherwise IS
DANGEROUS. For instance, the 13-inch
Electro home ( G07-904) monitor " flyback"
looks identical to the 19-inch Electrohome
(G07-905) monitor " flyback". In fact, there
is even a 19-inch Electrohome (G07-905)
monitor (which is an obsolete model) with a
similar looking "flyback". NONE OF
THESE ARE INTERCHANGEABLE!!
7
■ PS·U45
IPI DAIUHTH
E I C
, CHECK FOR BROKEN
WIRES; BAD LAMP
SOCKET
NO
1
YES
YES
REPLACE
TRANSISTOR
NO
Chart 2
PROBLEM
ONE CONTROLLED LAMP ALWAYS ON
YES
NO
CHECK BASE
VOLTAGE OF
DRIVER TRANSISTOR
6. You CAN change any of the parts between
the G07-904 and G07-907. They're essen-
tially the same monitor except that the G07-
907 has a vertically mounted picture tube.
If there is any doubt about what parts dn be
swapped between each manufacturer's 19-inch
and 13-inch models, compare the manufacturer's
part number between each one. If they match
up, they are the same part.
CHANGE
GAME PROM
YES
NO
REPLACE DRIVER
TRANSISTOR