Marantz SR7400

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I have a Marantz SR7400 receiver that is having a few problems. When I turn the receiver on, it comes on, clicks a few times and then turns off. The display will not come on either. I have been led to believe that there may be something wrong with the power supply circuit. I have the receiver apart but don't know where to begin. I have had some electronic experience in Engineering Physics class. But that has been a few years ago and I am a little rusty. Any help would be gladly appreciated.
 
Problems found on Power Supply

I know this is an old Thread but It seemed like a good place to write up what I have found and share it with the rest of you. I recently purchased a broken Marantz SR7400 AV receiver in hopes to fix or just use for parts. The guy told me it would run for a bit and then it would make a quick POP and quit. Let it cool off for a while and the same thing.

Here is what I found. There is a 3"x4" heatsink on the Power supply board that has four devices attached. I think they are regulators but did not bother to look. I noticed the heatsink was just a little loose. I pulled the power supply board after many screws and several cables later I had it out. Had to unscrew the mounts for the large transformer too and move it so i could wiggle the board out.

Looking closely I could see that a couple of the devices solder joint was broken loose as well as the mount for the heaksink. I corrected those and even beefed up the heatsink mounts hoping this would prevent this from happening again. Also, The there are eight diodes making up two bridges near the large relay that run rather hot and several of those solder joints looked to be bad so I redid all of those as well. I checked the entire board while having it out and the rest seemed to be good.
After putting it back together and a few hours of playing without fault, it's declared fixed.

One reason for posting this is I have seen several of these listed on eBay stating similar fault conditions. These are really nice receivers, I picked up mine for around $20 locally and now I have a nice receiver that I will use in my home theater.

Hope this helps someone.:)
 
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