Marantz 2325 Transformer problem
- Thread starter Leokarma
- Start date
Tod denneny
Member
Any idea Marantx 2325 powers on lights and relay clicks on....checked power supply board and no votalge to J801 ,J802
checked power coming in perfect ..checked votage at Sg-5ts and Sg-5tr 60v
any ideas or is the transformer done (fuse) Help thanks
checked power coming in perfect ..checked votage at Sg-5ts and Sg-5tr 60v
any ideas or is the transformer done (fuse) Help thanks
kaplang
Works for me !
This thread saved me.
The primary on the transformer of my Marantz 2325 was reading zero after the amplifier went south. It was working perfectly one minute and then the right channel started to crackle and the receiver went dead. Nothing! no power to it at all and no fuses blew. So on the bench it went and the first thing I discovered was the transformer primary was showing 0 ohms. Great! where am I going to get another transformer?. Nothing on Ebay so I did a google search with the following. "Marantz 2325 is dead" and that search led me to this thread and your contribution led me to the fuse able link of the transformer. I didn't even know it had one. I removed the transformer and took the side off as you show in the picture. I had to cut the copper shielding with my Dremel tool peeled it back and saw the problem. The fuse-able link was still OK but the very thin wire that goes to the fuse-able link from the Blue wire of the primary was broken. I think it must have melted. So! I was able to push the fusible link out of the plastic tube it was in and re solder it back to the blue wire. In the process of removing the link I destroyed the tube so I used a plastic straw to replace it.
On reassembly I soldered the copper shield back together and used some CA to put back the insulation cloth that covered the wires. I am now getting 1.7 ohms from the primary. This is good!!!!!
Now I have to figure out what caused this in the first place. Probably a bad output on the right channel driver board but that will be another story
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kaplang
Works for me !
Doesn’t t explain the 2 shorted output transistor
kaplang
Works for me !
Based on an AK members recommdation I should test all transistors of the driver board out off circuit with a good transistor testor. I didn’t have one so I bought an Atlas DCA55 and tested all the transistors using it. Non of them tested bad but I now have a good tester and am very happy with. At least I know I can properly test them in the future.
Going forward with troubleshooting the driver board I came across a resistor that is way out of spec. It is the white left bottom square showing in the picture. Let’s call it a resistor pack because the writing on its side saids it is a 0.2
ohm + 0.2 ohm k. One side measures .2 ohms and the other side measures 358 ohms out of circuit.
Can I use separate round resistors to replace the bad one as long as it is the same value? If so should I replace them all on both driver boards.
What wattage transistors should I replace them with? I’m thinking at lease 2 watts.
Going forward with troubleshooting the driver board I came across a resistor that is way out of spec. It is the white left bottom square showing in the picture. Let’s call it a resistor pack because the writing on its side saids it is a 0.2
ohm + 0.2 ohm k. One side measures .2 ohms and the other side measures 358 ohms out of circuit.
Can I use separate round resistors to replace the bad one as long as it is the same value? If so should I replace them all on both driver boards.
What wattage transistors should I replace them with? I’m thinking at lease 2 watts.
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petehall347
the brandy coffee man
200 mOhms ?
petehall347
the brandy coffee man
5 watts wire-wound seems about right .. 0.22 ohms . i would change all of them .
kaplang
Works for me !
The C496 transistor at location H714 right channel is testing as a diode and that’s wrong so I want to replace it. It’s a T126 package. What is a good equivalent for the C496 since that one seems to no longer be available. NTE shows a equivalent but I want to stay away from NTE if possible.
George
George
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kaplang
Works for me !
Thanks
kaplang
Works for me !
Yes if it’s tested In circuit that is the case but I tested it out of circuit so a transistor is how it should test as. The test showed no collector.
petehall347
the brandy coffee man
b to e . be to c . 600mv ish one way only .. ce to e nothing both ways .
petehall347
the brandy coffee man
petehall347
the brandy coffee man
so b to e is open ?
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kaplang
Works for me !
Yes. The transistor would fail when it warmed up and cause the receiver to go into protection. Now it’s just stuck with an open hot or cold.
petehall347
the brandy coffee man
damn things . was lead to believe years ago solid state would not break down .
