Rowe CD-51 Right Channel Issue

thepita007

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Hello

I recently picked up a rowe cd51. The right channel is very weak and very distorted. I tested the speakers and they were fine. I have attached pictures of the wiring as it doesnt match what is in the manual curious if anyone else has seen something like this. I have checked the fuses and they are all good. Also I do not see any swollen caps.
 

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JUkebox

What doesn't match about it? How did you test the speakers? Did you try switching the channel leads at the transformers? Maybe from E5 to E4.
 
1. Check the speaker crossover network circuit board for cold solder joints.

2. Check the amplifier circuit boards for cold solder joints, particularly at the connector header pins.

3. Test the amplifier output transistors for an open transistor. If one of the output transistors were shorted, one would blow one of the four fuses on the driver boards.

4. Could be an open resistor on one of the driver boards.

5. Could be some bad electrolytic capacitors on any of the amplifier boards. Test them with a capacitor ESR meter.
 
What doesn't match about it? How did you test the speakers? Did you try switching the channel leads at the transformers? Maybe from E5 to E4.

Tried switching channel leads no effect.

I tested the speakers by swapping left for right.

The wires that do not match the manual are on the crossover board. I believe the manual shows two orange and black wires but there is only one.

Ken I will try your suggestions when I get home tonight.

Thanks All
 
I tested the driver board on the bad channel and everything tested ok so I replaced a blown fuse it had. I then swapped the driver boards and removed the fuses from the driver board on the channel I knew was bad. Powered the jukebox on and the one channel is working great. So now I know the two driver boards are good. So I am assuming the transistors are shot on the bad channel.
 
While looking over the crossover board I noticed resistor R4 was cracked. Would it be ok to replace this resistor with a metal oxide resistor with matching value? I am having trouble finding a wirewound 47 ohm 2 watt resistor.

Thanks,
 
Last edited:
While looking over the crossover board I noticed resistor R4 was cracked. Would it be ok to replace this resistor with a metal oxide resistor with matching value? I am having trouble finding a wirewound 47 ohm 2 watt resistor.

Thanks,
Will it work? Yes. Would I recommend doing it? No. The original resistor was wirewound for a reason.

MrGorf said:
Not to hijack the thread, but why is there a black wire connected to E1 on the right channel but not the left?
No idea, but apparently it's the right channel with the problem so maybe it's worth trying without the wire.
 
If you can not get a 47 ohm resistor make one up by putting two in series but they would each have to be 2 watts.

The black wire goes to E1 (it could go to E1 left or E1 Right) it is the ground for the speakers the pink and violet go to E6 left & right which is the maximum output (E7 left & right are not normally used and are reserved for special applications)

Regards
Alan

Alan Hood
ami-man
UK
 
The black wire goes to E1 (it could go to E1 left or E1 Right) it is the ground for the speakers the pink and violet go to E6 left & right which is the maximum output (E7 left & right are not normally used and are reserved for special applications)

Thanks. I saw the other black wire going to the common terminal on the block between the two transformers and thought E1 might be an output tap.
 
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