Inverting op amp follow up

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  • DAVEMAC02
    Member
    • Jun 2018
    • 17
    • United States
    #1

    Inverting op amp follow up

    Follow up to my op amp diagram of Q208 FET and IC204 for NJM 2068M op amp. I took took the following DCV readings on the Q208 (2SK246) and IC204 pins:
    pin 1 0v, pin 2, 0v, pin 3 0v, pin 4 -15.6v, pin 5 0v, pin 6 .08, pin 7 0v, pin 8 +15.9v

    Q208 source -.006, gate -15.5v, drain -.102. These readings are from the op amp Q208 that has no output on pin 1. I don't know what state ie (On or Off ) Q208 should be when op amp is working correctly. This circuit is on the filter/limiter stage of the PA system. Any help is appreciated. Thanks
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