81 General Procedure

This section describes troubleshooting procedures in detail sufficient for a person with moderate technical ability to understand. However, for those interested in gaining more information 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 for $5.00 each, or from your distributor.

8.1.1 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 V 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 heopens the cabinet.

Keeping these observations in mind, use the understanding of game operation gained from Section III, Description of Operation and Section IX, Schematics. Next narrow down the suspected cause of the trouble to a specific area or areas of the game: coin mechanism, TV monitor, harness or front panel controls (switches, lamps, speakers), electronics tray, printed circuit board or 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 walloutletand is no longer fully seated in the receptacle, power ON/OFF set tn the OFF position, or a rear panel access door that is not fully closed (thus causing the interrupt switch to block the AC power path to the game).

8.1.2 Locating the Trouble Cause:

Once a problem 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 properly 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, ctc. 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 to the printed circuit board. If there is still no signal, then systematically check back through the various components of the sound generation circuit.

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 know-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 substitution also. Substitute both a known-to-be-good PCB and TV monitor. If the trouble still persists, the harness must be at fault.

The test equipment for use in troubleshooting is discussed in paragraph 8.2.

8.1.3 Correcting the Trouble Cause:

In practice, the steps required to correct troubles can range from simple adjustments (correctly seating the PCB in its edge connector, 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 cxercised when removing integrated circuit devices and discrete components. Use a 40-watt maximum soldering iron with a small tip designed especially for IC work. To remove an IC device, follow this procedure:

Clip all leads and lift the IC package out.

leaving two rows of leads. Then remove leads individually with a soldering iron and needle-nose pliers. Finally, evacuate the holes with a solder sucker. 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.

The microprocessor, read-only memories, and random-access memories are removed by simply pulling them out of their sockets. When piacing them into their sockets, make certain they are placed in the correct socket.

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 are 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.

8.1.4 Verifying Correct Game Operation:

After locating and correcting the cause of a trouble, re-energize the game and perform a final check by placing the game in the self-test function, then check for correct operation during game play. Doing this will verify that your troubleshooting 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 this was done properly, then start the troubleshooting steps over again. Keep in mind that there may be more than one trouble at a time, and that correcting one trouble can sometimes bring previously undetectable troubles to light.

This verification is especially important when the original trouble had been intermittent, that is, was not happening all the time.

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