Firepower II
Williams, 1983Have this MPU on the bench. There was no voltage at TP7. Replaced defective battery holder and now I have voltage at TP7, but it fluctuates between about 3.0V to 4.4V give or take. Happens over about a minute, up and down. Before D17 I get voltage swings from about 5V to 3.4V. D17 tests good.
Ideas what is wrong?
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Shrewsbury, MA