RiotClass
New Member
Hello,
I recently got my father in laws old Marantz turntable and amp so I could have a go at some vinyl .
When I tested the amp the lights were on (see pic) but no sound coming from the speakers and no movement in the power leds no mater what I did with the volume knob.
I know enough about electronics to be annoying but fault finding to a component level is not a strong point of mine.
I got myself a service manual for the PM 225 since it looked to have similar internals.
I checked the transformer the voltages seem fine. About 30V coming off the secondary winding.
Next I checked the output of the bridge rectifier. I'm getting 27VDC from one side and -42VDC from the other.
Also the 15VDC output on the back is reading zero volts so i think that has something to do with it.
I've also noticed that a couple of bigger resisters are running super hot.
This is where my electronics knowledge sort of ends. Any help would be appreciated.
Thanks in advanced for any legend who can help me out.
I recently got my father in laws old Marantz turntable and amp so I could have a go at some vinyl .
When I tested the amp the lights were on (see pic) but no sound coming from the speakers and no movement in the power leds no mater what I did with the volume knob.
I know enough about electronics to be annoying but fault finding to a component level is not a strong point of mine.
I got myself a service manual for the PM 225 since it looked to have similar internals.
I checked the transformer the voltages seem fine. About 30V coming off the secondary winding.
Next I checked the output of the bridge rectifier. I'm getting 27VDC from one side and -42VDC from the other.
Also the 15VDC output on the back is reading zero volts so i think that has something to do with it.
I've also noticed that a couple of bigger resisters are running super hot.
This is where my electronics knowledge sort of ends. Any help would be appreciated.
Thanks in advanced for any legend who can help me out.
