Service manual

Wells-Garnder Color Vector Monitor Guide
Page 64 of 73
Zanen's Standard Instructions:
This monitor repair kit is designed for the Wells-Gardner 19K6100 X-Y color monitor, as used
in Tempest, Space Duel, and other Atari color X-Y games.
Be sure to install all the parts on the monitor even though many of the original parts seem to be
working fine. Age, humidity, and temperature will cause the value of electrolytic capacitors to
change. Also the other semi-conductors included fail often. Install them all.
Each capacitor is polarized and should only be inserted in the proper direction. Watch the
polarity markings on each capacitor. On the topside of the monitor board where each capacitor is
located is a circle with a plus sign next to one of the holes. The plus sign indicates where the
positive (+) lead of each capacitor is to be installed.
Important: It is possible for a failure on the game logic board to cause the monitor to fail. There
is a simple test to find out if the game board caused the monitor to fail. To perform the test you
will need a voltmeter. Set the voltmeter on the DC voltage scale and measure the voltage on the
lead of R600 and R700 (fuses) of the deflection board. These are connected to the plug with wire
colors yellow (R600) and orange (R700). The correct voltage should be in the +0.5 to -0.5 volt
range (basically zero volts). The voltage will fluctuate because of changing deflection signals. If
the measured voltage is between 5 and 15 volts (positive or negative), then check the X and Y
amplifiers on the GAME board. Also check for broken potentiometers on the game board.
Important: It is very important to resolder all the molex connectors soldered to the monitor
circuit boards. Plugging and unplugging these connectors can crack the solder joints.
End of original Zanen installation instructions