The regulators failed regularly in these amps because they ran too hot. When they failed, they often destroyed all of the op-amps in the amp. If you don't have any shorted outputs or power supply FETs, the regulator damage may be the only thing you need to repair but expect at least several hours work and expect to replace at least about 20 parts. Refer to the following:
http://www.bcae1.com/temp/mtx500dregulatordamage01.swf
http://www.bcae1.com/temp/mtx500dregulatordamage01.swf
Did you look at Perry’s picture in the link he posted?
It appears he states what the burnt components are & what to replace them with; which are 390 ohm resistors to reduce power dissipation in the regulator transistors. He also states what transistors to replace, zener diodes & more.
All the best & I hope you get it working.
It appears he states what the burnt components are & what to replace them with; which are 390 ohm resistors to reduce power dissipation in the regulator transistors. He also states what transistors to replace, zener diodes & more.
All the best & I hope you get it working.
Yeah 1/2-watt resistors will likely be ok. I’m guessing 1-watt resistors would not hurt for that application either.
The zener diodes should be labeled with there part number, which then you can use to find there specs. Take them out carefully & look at the number.
They are likely 1N4746 zener’s; that’s what they are in my blown MTX 250D, should be the same for your 500D. They are 18v zener diodes, 1-watt I believe. Again you can take yours out to be sure.
The zener diodes should be labeled with there part number, which then you can use to find there specs. Take them out carefully & look at the number.
They are likely 1N4746 zener’s; that’s what they are in my blown MTX 250D, should be the same for your 500D. They are 18v zener diodes, 1-watt I believe. Again you can take yours out to be sure.
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