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 should be mounted on the bottom at the side opposite the game board, under the game board.

The inside of the cabinet can be rough sprayed with flat black paint to improve heat absorption and help transfer the heat to the outside world.

Whenever possible, some judicious bottom vents located under the games board and the chassis edges of the power supply with some well screened upper vents under the table top (or rear of upright cabinets) should be used to provide some convection cooling. This alone would solve many of the existing heat failure problems.

3.)Erratic Operation Due To Line Noise

Most coin operated games operate in an environment with electromechanical pinball games and other games with solenoids, relays, and motors that generate fairly high spikes on the power lines. These high frequency spikes are generally passed through the usual power supply with very little attenuation since they are above the regulators frequency response. These signals can cause false responses from the game circuits and are extremely difficult to isolate since they may occur randomly.

This problem can be solved by using high noise immunity circuitry and filtering all lines, or by installing an expensive AC line filter. A much simpler and far less costly solution, however, is to use an electrostatically shielded transformer with a high frequency bypass on the secondary in the power supply. All Adtech Power supplies use this system and it has completely solved the noise problems of several game manufacturers.

4.)Erratic Operation At Low Line Condition

As more sites cram more games into a given floor space, the power lines are loaded more severely and the line voltage drops. I have seen 3 and 4 games operated from an undersized extension cord. Also during peak periods, power companies may reduce the line voltage 5% to reduce generator loading. This means that many games are nearly permanently operating under low line condition.

While most O.E.M. supplies are rated to operate from 105 to 125 volts, under extensive operation in the higher heat environment of the video game, they may drop out of regulation causing excess ripple and erratic operation as high as 110 volts. A common symptom of this problem is a premature end of game signal. Adtech Power uses a 20% larger transformer to provide an extra 57 0 reserve to prevent this problem and permit operation as low as 100 volts when hot.

Using a higher rated supply as previously mentioned is another way to solve this problem.