Help with Marantz 2238b, Only runs out of one Side

[SudoSpencer]

I bought a Marantz 2238B and when I tried it out only one side was playing. I popped the case and found that there is a bit of corrosion and rust sadly. Also the little spot labelled Q720 is completely unattached.

I am trying to learn about electronics but don't have a clue what this does or is. Can someone help me? Is this what is causing the issue. Is it safe to run without this piece soldered in?

 

[runningdog]

Welcome to the Marantz Forum on audiokarma!

I've attached a picture of a stock 2238B main board, with Q720 pointed out. Q720 is a diode (it is the little black and green 'gumdrop') and both ends should be soldered to the board. Is this the part that is not attached on your board?

Could you provide a clear picture of what yours looks like?

 

[SudoSpencer]

That is exactly what it is. Sadly it has come completely undone. Also, a large portion of the things near it have become greenish with corrosion.

Is it fairly simple to replace the diode? It looks like I just get a new one and solder it in right?

EDIT: I'll get photos up tomorrow if I can.

 

[runningdog]

It is an easy part to replace. But I'm curious if it was deliberately disconnected or if the connection corroded away. If the former then of course the question is why? And if the latter then there could be other parts equally corroded.

Typically to troubleshoot a dead channel the controls are all cleaned and treated as a first step. But when you have a part clearly detached then dealing with it first makes sense.

Pictures will be good.

 

[SudoSpencer]

Here are the photos I took. As you can see in photo one there is a lot of green corrosion and even some rust. I think it was water damaged. As you can see in photo 2 the Q720 diode is completely missing.

 

[petehall347]

looks like c706 also missing .
can you get a good pic of other side of board ?

 

[SudoSpencer]

Honestly I'm starting to think this is over my head. Maybe I'll see if I can find someone at a local repair shop who has an idea of what cost would be to fix it. I started to try to pull the board out to get a shot of the underside and even that seemed daunting. Pulled 4 screws but it still is connected at several points it seems.

 

[runningdog]

Having it looked at is a good idea. If those two components were removed or if they corroded away then there a likely other components that need to be checked too.