Shorting the gate to ground does clear the fault. The thermistor wires are in a sheath, but they feel like they are twisted in there. I could shorten them quite a bit, also.
If the LM339 output isn't going to zero, wouldn't adding the 100k resistor from the LM339 output to ground allow the output to go to zero without significantly affecting voltage to the transistor? On the other hand, if that worked, that would indicate a problem in the LM339 because the output goes to ground in the off state.
If I'm following you, the capacitors will act as filters to smooth any spikes that are induced from either the AC supply or the long leads on the thermistor.
Would switching the FET for a different transistor help? How is sensitivity measured in a transistor?
About the voltmeter on AC- I assume that any AC component is going to be a bad thing- right?
If the LM339 output isn't going to zero, wouldn't adding the 100k resistor from the LM339 output to ground allow the output to go to zero without significantly affecting voltage to the transistor? On the other hand, if that worked, that would indicate a problem in the LM339 because the output goes to ground in the off state.
If I'm following you, the capacitors will act as filters to smooth any spikes that are induced from either the AC supply or the long leads on the thermistor.
Would switching the FET for a different transistor help? How is sensitivity measured in a transistor?
About the voltmeter on AC- I assume that any AC component is going to be a bad thing- right?