Marantz 4300 question?

AubRock

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Ok guys need some advice. I am getting ready to go pick up a Marantz 4300 quadradial receiver. Guy wants a couple hundred cash. The issue with it he says the unit will not power on. But the relay does kick on. Said he was gonna have it serviced but never got around to it. Any information on what may be the cause of this. Fuses, Power supply board, power switch?? Or something else. And is it worth the trouble? Pics below.

Hopefully I posted this in the right spot.

Any info or help is greatly appreciated amp
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Not familiar with this unit, but what strikes me is that the relay clicks when the power switch is in ON?
If true I would think it is getting power, it's possible that there is a PS issue and/or all the lamps are burned out.
 
Ok guys need some advice. I am getting ready to go pick up a Marantz 4300 quadradial receiver. Guy wants a couple hundred cash. The issue with it he says the unit will not power on. But the relay does kick on. Said he was gonna have it serviced but never got around to it. Any information on what may be the cause of this. Fuses, Power supply board, power switch?? Or something else. And is it worth the trouble? Pics below.

Hopefully I posted this in the right spot.

Any info or help is greatly appreciated amp
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Well.. if it clicks on that's good, real good. I would buy it knowing I could repair it... overhauled a number of them quite a few years ago. They have known issues, mainly with 2sc458 type transistors sprinkled through out, we used to replace all of them if the unit was in for a major repair. But it the relay clicks I would expect a basically good unit perfect for a rebuild... or, if it works, use it as is for awhile.. clean controls, etc. If the relay clicks I'm thinking it might work with all controls in the right position. There are certain cautions you might take... like check offset at speaker outputs, protection relay will not click if that is excessive.. and idle current.. but I suspect it will be a minor repair to make it work.
 
Went ahead and bought it. I’m thinking it’s something minor. I couldn’t pass it up for the price. I haven’t had time to dive into it yet. Plan on it this afternoon. I will post later after I find out more. Very grateful for the responses
 
there on tricky setting on the amp. on the back there is a remote control button has to be set right - double check - looks right on picture 9 though.

check if the amp works with a headset, and put signal cable straight into the amp input on the back and you should hear some buzzing when you put your finger other end of the cable.

let us know how it works out.

Good luck
Robin
 
???

it's obviously powering on if it clicks. I'm guessing the power switch is fubar. that was the issue on the 4300 I did. look there first.

the 4300 I did had a lot of the same issues that I find in the 4270s.
hoping its a good working unit once you get the lights on.
there are a bunch of trouble makers in those damn quads.

FWIW, the one I restored cost the owner a large amount. But, as he played with it, he was texting me about how much he liked it. The last text I got was "Screw it, I'm calling in sick to work tomorrow!"
 
Ok so I haven’t tried to power it up yet. Two jumpers are definitely missing and the black plastic plate that secures it to the back is broken. So now it’s just dangling loose. Not sure if they even sell that part anywhere.

Next I was going to look at the power switch. Is it possible to test it with a multimeter?
 
Ok so I haven’t tried to power it up yet. Two jumpers are definitely missing and the black plastic plate that secures it to the back is broken. So now it’s just dangling loose. Not sure if they even sell that part anywhere.
{SNIP}

The pre-main jack plate from many other Marantz receivers and integrated amps will fit, even some from 2 channel models. Check the auction site.

Tom
 
The pre-main jack plate from many other Marantz receivers and integrated amps will fit, even some from 2 channel models. Check the auction site.

Tom

Cool thanks. Wonder if one from another brand amp would work? I have a Marantz 2275 but obviously I don’t wanna take parts from that. But I have some other junk amps.

Also do you need to be a subscriber to browse the auction site?
 
I believe the auction site being referred to is eBay. BarterTown on this website is subscription based.
 
Any advice on what fuse to get. Service manual tells me I need a 300 mA 250v. I live in a small town and no one carries that small a fuse. So I’m searching online now. Best site for fuses? Type? Brand? Slow blow, fast blow?
 
Update:

So I finally found the fuse. 300 ma 250v slow blow. Hope that’s right. After cleaning all the pots and switches and connections I now have sound. Right channel good. Left channel I got low sound and some bad crackling and popping. Swapped speaker connections and tried iPod hooked to Aux and tried Fm. Same on both. Remote/local switch is right. Quad mode switch in 2 channel. All 4 jumpers connected. Although I used rca cables on the front pre-out main in because I only have two sets of jumpers. I did notice on the power supply board, looks like C804, C805, C808 & C809 are leaky. On Mouser looking to order replacements now. Could this be my problem?
 
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