Hello everyone, I'm new to the electronics repair hobby. I could not afford a Luxman M-117 so I purchased a broken one and figured I would try my hand at repairing this one. So here goes.... The right channel has -74 volts DC at the speaker terminals all of the output transistors are showing the same -74 volt on the emitter leg. Should I remove all of the output transistors and test? I have attached a service manual. Any help would be appreciated?
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Re: Luxman M-117 amplifier
Look at the bright side. You got a working channel and a non working one. With amps I work backwards. So check the finals first and you also can swap from side to side. It also could be the driver or the pre-driver. Look at the block diagram on page 6. In the final stage there are large 0.22 ohm 2w resistors one for each transistor, check those too if they went open.Last edited by CapLeaker; 08-31-2022, 02:30 PM. -
Re: Luxman M-117 amplifier
Cool, thanks for the pointers. So if any of those resisters goes open it would cause this condition?Comment
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Hi guys
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Hi guys
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