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Williams, 1978You're currently viewing posts by Pinsider cody_chunn.
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I'm right there with you brother:
WMS SYS7 TEST RIG (resized).JPG
A place to start is checking for life on the CPU. Do you have a logic probe? You should be seeing pulsing on pins 4, 5, 9-20, and 22-33, 37,38,and 39.
If you're unsure of the reset circuit, momentarily tap a jumper from ground to pin 40 of the cpu.
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