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Old 10th October 2012, 05:36 PM   #521
AndrewT is offline AndrewT  Scotland
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24.75Vgs !!!!!
that sound more like an open G to S circuit.
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Old 10th October 2012, 05:48 PM   #522
KWS1 is offline KWS1  United States
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Not sure whats happening. I have spend many hours ..days going over eveything still no voltgage. I added a 3.3 k to R 4 thinking that may be it. Could the mosfets be bad. or did I not measure correctly. Thanks, Allan
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Old 10th October 2012, 07:26 PM   #523
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Aren't the mosfets swapped?
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Old 10th October 2012, 07:28 PM   #524
KWS1 is offline KWS1  United States
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I am not sure what you mean.
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Old 10th October 2012, 07:34 PM   #525
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P channel instead of N channel and reverse.

Last edited by bobodioulasso; 10th October 2012 at 07:39 PM.
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Old 10th October 2012, 07:51 PM   #526
KWS1 is offline KWS1  United States
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I just checked Q3 & Q4 and they look correct...except I mixed the matched pair. Would that make it not work?
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Old 10th October 2012, 08:44 PM   #527
Itsmee is offline Itsmee  England
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Quote:
Originally Posted by KWS1 View Post
24.75 volts...
Stupid question, did you measure from the junction of R11 & source to the gate and R12 & source to the gate?
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Old 10th October 2012, 09:29 PM   #528
KWS1 is offline KWS1  United States
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It looks like zero....the middle pin is 24 volts
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Old 12th October 2012, 08:04 AM   #529
Itsmee is offline Itsmee  England
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If adjusting P1 & P2 has no affect on the gate voltages, I would suspect you have a gate source short.
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Old 12th October 2012, 01:38 PM   #530
KWS1 is offline KWS1  United States
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How should I proceed.... Thanks
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