We suspicion that one of the double pole double throw switches has a momentary short from the 12 volt side to the ground side, but I can not confirm it with a voltmeter. The digital voltmeter probably averages several samples, but I never see a rise when I activate the switch very slowly.  Tried an old analog gage and still could not identify it. Tracy is convinced that we are hitting the circuit on the
 chip with 12 volts to blow it. Now that I have the simple one toggle switch, no more chips have been blown in nearly an hour of running over the last two days. With the 3 switches hooked to pin 30 it was instantaneous death.

The switches are either from B&C or an orlando aircraft surplus shop. The two sources for switches appear to come from the same Mexican supplier, but do not know the details other than appearance.

Bernie

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