I plan to add more machines as time permits and as I get more information. If you have information on machines that I don't have listed here, please send it to me and I'll post it here too.
MPS-A13 (20 each) - Single lamps or under-playfield transistors (2N5875)The three 2N3055 transistor (Q58, Q62, and Q64)) are actually driven by MPS-U45 transistors (Q57, Q61, and Q63 respectively), due to the high power demand of the associated solenoids, which is more than the MPS-U45 can handle. This three driver circuits were designed to drive solenoids that required a lot of power to energize (for example, resetting a bank of 5 drop targets). Unfortunately, the need for additional high powered driver circuits arose and presented a problem, since the driver board only had 3 such circuits. To solve this deliema, Gottlieb placed additional high power driver transistors (2N5875) underneath the playfield near the desired coil(s), then used the MPS-A45 circuits on the driver board to drive them. These high-powered transistors then drive the solenoids. These transistors and the ones on the driver board are easy to replace once the defective ones have been identified. Clay's System-80 Repair Guide tells how to identify shot transistors. If you'd like to find out which driver transistor goes to which driver connector tab, Click Here.
MPS-U45 (38 each) - Single or multiple lamps, relays, solenoids, or 2N3055 transistors
2N6043 (3 each) - Solenoid coils
2N3055 (3 each) - High powered solenoids
Finally, the driver board provides 5 signals to the System-80 sound board. The first 4 signals come from Z13 (SN7404); SOUND1, SOUND2, SOUND4, and SOUND8. The fifth signal, SOUND16, comes from Q10 (MPS-A13). These signals are decoded by the sound board to produce the desired sound effects.
MPS-U45 (10 each) - Multiple Lamps
Click on a machine to see the info:
All content posted on this page, unless otherwise noted, is the
exclusive property of Steve Kulpa
and may not be borrowed, copied, downloaded, reproduced, or pilfered in any way with out prior permission