Marantz SM-8 help

maclvrbr

AK Subscriber
Subscriber
Purchased an SM-8 amp in need of repair. Where does the ground wire go? See pic. Is the voltage selector correct or should it be 120V? Where can I find the screw in fuse holder? A replacement? The amplifier states that an 8 amp fuse is needed. The fuse and holder I am using are from the preamp. With this fuse in place I am only getting 30 ACV to the fuse holder, tested inside the amp wiith DMM. Ideas?
 

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The amplifier is not coming out of protect mode. The rail volatge I am geting is 30v on large filter caps and 15 on the smaller caps. I disconnected the power to the amplifier assembly board both pos and neg. This was being fed from the power switch assembly board. Once disconnected the relay engaged and voltage came up to 50v and 35 volts, DBT in circuit. I Then connected power to the amp board again and am getting 0 voltage on the out put rails. Any ideas are appreciated
 
It should be set to 120v in USA. I would rewire it with a better plug/wire, and suggest not using a chassis ground from the wall plug.
Us your digital volt meter, set on ACV ;), and follow the power into the unit.
Make SURE you wrap your probe in masking tape so only the tip is exposed.


Most older Marantz units do not ground the chassis. doing so can be unhealthy for the guy that has to work on it.
Without a schematic, Its hard to say if it did or not. The SM7 does not use a ground.
 
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