THERE IS NO WAY TO MEASURE THE RESISTANCE OF A MOSFET OTHER THAN DETERMINING IF IT IS SHORTED, WHICH WILL BE INDICATED BY A CLOSE TO ZERO OHMS MEASUREMENT ACROSS ANY TWO OF THE THREE LEADS. I DO HAVE A METHOD OF TESTING MOSFETS, BUT IT GOES BEYOND THE SCOPE OF THIS FORUM AND REQUIRES AN EXPENSIVE HIGH IMPEDANCE MULTIMETER TO DO SO. YOUR IRFZ44N SHOULD BE MANUFACTURED BY INTERNATIONAL RECTIFIER AND THE EXACT REPLACEMENT SHOULD BE OF THE SAME MANUFACTURER. THESE MOSFETS ARE PROBABLE IN THE POWER SUPPLY OF YOUR AMPLIFIER, AS THEY ARE RARELY USED IN THE OUTPUT SECTION. IF YOU FIND THAT ONE IS SHORTED, THEN THEY ARE PROBABLY ALL SHORTED WITHIN THAT BANK. THE OTHER BANK ALSO MAY OR MAY NOT BE SHORTED......V
Answers & Comments
THERE IS NO WAY TO MEASURE THE RESISTANCE OF A MOSFET OTHER THAN DETERMINING IF IT IS SHORTED, WHICH WILL BE INDICATED BY A CLOSE TO ZERO OHMS MEASUREMENT ACROSS ANY TWO OF THE THREE LEADS. I DO HAVE A METHOD OF TESTING MOSFETS, BUT IT GOES BEYOND THE SCOPE OF THIS FORUM AND REQUIRES AN EXPENSIVE HIGH IMPEDANCE MULTIMETER TO DO SO. YOUR IRFZ44N SHOULD BE MANUFACTURED BY INTERNATIONAL RECTIFIER AND THE EXACT REPLACEMENT SHOULD BE OF THE SAME MANUFACTURER. THESE MOSFETS ARE PROBABLE IN THE POWER SUPPLY OF YOUR AMPLIFIER, AS THEY ARE RARELY USED IN THE OUTPUT SECTION. IF YOU FIND THAT ONE IS SHORTED, THEN THEY ARE PROBABLY ALL SHORTED WITHIN THAT BANK. THE OTHER BANK ALSO MAY OR MAY NOT BE SHORTED......V