One of my Mark Levinson 2 ML-2s is kicking off at turn-on. Substitution found a malfunction in the regulator board. Which ever amp I put the good board in works and the other with the suspect board does not. I had hoped it would be the thyristor as it seemed to be the highest power and hottest device on the board and therefore the most likely to fail. Took in out and tested it at 30 volts and .6 amps. Touching the anode to gate turns it on and it stays on till the current drops to 9 ma. It will turn back on with current as low as 10 ma when re-touching the anode to gate. Seems like it is good and that is about as far as my knowledge will take me. I am hoping for either some good tech guidance from the forum or a recommendation of a fair and competent repair service that is well familiar with these boards I just had my Quads rebuilt last year and have now lost an amp. Hope you can help.
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