Atari STEEPLECHASE, Operation, Maintenance & Service Manual

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VI. Troubleshooting and
6.1 GENERAL PROCEDURE
This section describes troubleshooting pro­
cedures in detail sufficient for a person with
moderate technical ability to understand. How­
ever, for those interested in gaining more in­
formation on video game technology, especially
the electronics, we recommend reading the
Video Game Operator's Handbook, manual
no. TM-043. This book is available from Atari,
Inc., attn. Customer Service Dept., 2175 Martin
Avenue, Santa Clara, CA 95050, .'or $5.00
each, or from your distributor.
6.1.1 IDENTIFYING THE TROUBLE AREA:
The first
troubleshooting step should be to note all observable trouble
symptoms. Examples of symptoms are: depositing a coin
produces no game response, no sound coming out of the
speaker at any time, no picture on the TV screen. At the
same time also note the game features that still work. A
systematic way of checking game operation is to perform
the functional check given in Section IV of this manual.
Carefully train your eye to pick up all clues; by doing this
an experienced troubleshooter can often spot the cause of
a trouble even before he opens the cabinet.
Keeping these observations in mind, use the understand­
ing of game operation gained from the Theory of Operation
(Section Ill) and the schematic drawings (Section VII).
Next narrow down the suspected cause of the trouble to a
specific area or areas of the game: the coin mechanism, TV
monitor, harness and front panel components (switches,
lamps, LEDs, pistol assembly), electronics tray, printed
circuit board, and power cord. Be careful not to overlook
possible trouble areas that may seem too obvious: a power
cord plug that has worked loose from the wall outlet and is
no longer fully seated in the receptacle, or a rear panel ac­
cess door that is not fully closed (thus causing the inter­
rupt switch to block the AC power path to the game).
6.1.2 LOCATING THE TROUBLE CAUSE: Once a prob­
lem has been narrowed down to one or more areas, the next
step is to perform various tests and measurements to isolate
a specific cause of the trouble. Remember that sometimes
a very complicated problem, such as erratic game operation,
can be traced to a simple cause-the printed circuit board
not being fully seated in its edge connector. Start with the
most suspect area and trace backwards from the point
where the trouble is first observable, using a process of
elimination to eventually locate the faulty component,
connection, etc. For example, if no sound is audible during
game play, first check for a signal at the speaker leads. If
no signal is present there, go back through the wiring har­
ness connections to the printed circuit board. If there is
still no signal, then systematically check back through the
various components of the sound generation circuit.
Repairs
Substitution of parts is a legitimate and easy way to
isolate the cause. For instance, if the PCB is the suspected
trouble area, remove it and substitute a known-to-be-good
PCB. Then check for correct game operation. Similarly, to
check the TV monitor, connect the game to a known-to-be­
good monitor. The harness can often be checked by sub­
stitution also. Substitute both a known•to-be-good PCB and
TV monitor. If the trouble still persists, the harness must
be at fault.
While locating the trouble cause, use the technical
descriptions in Section 111 as guides for correct circuit­
level operation, and the schematic drawings of Section VI I
as roadmaps for tracing signal flow paths.
The test equipment for use in troubleshooting is dis­
cussed in paragraph 6.2.
6.1.3 CORRECTING THE TROUBLE CAUSE:
In prac­
tice, the steps required to correct troubles can range from
simple adjustments (fully seating the PCB in its edge con­
nector, changing the setting on a potentiometer, adjusting
the picture controls on the TV monitor) to repair of loose
connections and replacement of defective parts. Extreme
care should be exercised when removing integrated circuit
devices and discrete components. Use a 40-watt soldering
iron with a small tip designed e,pecially for IC work. To
remove an IC device, follow this procedure:
Remove all solder from both sides of the PCB, first
melting it with the hot iron and then sucking up the
molten solder with a Soldapullt® solder sucker. After
all the solder is gone, remove the IC device by gently
prying up. Afterwards clean the area thoroughly, using
an approved PCB cleaning solution to remove any traces
of flux and dirt. Alcohol will do in a pinch, if necessary.
Insert the new IC device using an IC insertion tool,
making sure that the reference notch is oriented correctly
and that the device's leads arc not bent during insertion
into the board. Afterwards, be sure to solder each lead on
both sides of the PCB, using as little solder as possible.
After soldering, clean the area thoroughly to remove the
flux.
Observe the same removal and insertion procedures
when replacing discrete components. Trim the leads as
close as possible and be sure to orient diodes and capacitors
correctly.
6.1.4 VERIFYING CORRECT GAME OPERATION:
After locating and correcting the cause of a trouble, re­
energize the game and perform a final check on correct
game operation. Doing this will verify that your trouble­
shooting was correct. If the game operation is still not
correct, go back and double-check your work. Make sure
that any replaced components were installed correctly. If
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