Im working on a Kenwood and repaired a lot on the crossover board and currently stuck. I have +-16, 20 & 55 voltage now and a perfect sine wave on left and right channel CEN3 but when I probe the outputs I have a square wave on them and nothing on the speaker terminals. The relays engage on turn on also. I think it’s a ground issue but can’t find where ground is missing. The attached image is what’s on the outputs it stays like this rather sound is playing or not.
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If you reduce the signal, do you get a sine wave?
With the relay engaged (no signal), do you read 0 ohms across the terminals for each channel?
If you jump the terminals for each channel, do you get audio to the speaker terminals?
With the relay engaged (no signal), do you read 0 ohms across the terminals for each channel?
If you jump the terminals for each channel, do you get audio to the speaker terminals?
No with the signal turned down the square wave still is present. I’m confused about 0hms across the speaker terminals. Are you referring to black probe on negative speaker terminal and red probe on positive speaker terminal do I have 0 ohms?
Across the relay terminals, not the speaker terminals.
After looking at the diagram, the feedback is being taken from beyond the relay so the square wave is normal with the relay open.
After looking at the diagram, the feedback is being taken from beyond the relay so the square wave is normal with the relay open.
I just noticed a difference between the two relay coils. One relay has 50volts and 25 volts across the coil. The second relay has 25volts and 2 volts across the coil. I can’t figure out where the missing 50volts should come from.
Let the relay engage and then look for signal on the two halves of the contacts for each channel.
If the relay is closing, the contacts are bad. You may be able to clean them but the relay should be replaced.
Did you try bridging the solder connections on the board to see if the amp produced audio?
Did you try bridging the solder connections on the board to see if the amp produced audio?
Re, post #8:
The relays likely have 24v coils that are connected in series. Each coil has ~25v across it in the amp.
The relays likely have 24v coils that are connected in series. Each coil has ~25v across it in the amp.