Sorry for absence. No internet access available.
Am I correct about the following?:
Power switch on, but no activity?
When you disconnect CP553, display and amp become active?
Once system is active, you are able to reconnect CP553?
Is there any indication of protection mode being active? Does relay stay on or does it cycle off and on? Do amps produce audio? (Use expendable speakers!)
Am I correct about the following?:
Power switch on, but no activity?
When you disconnect CP553, display and amp become active?
Once system is active, you are able to reconnect CP553?
Is there any indication of protection mode being active? Does relay stay on or does it cycle off and on? Do amps produce audio? (Use expendable speakers!)
Hi, no need for sorry’s, more than happy you are willing to help! I’ll try to explain from the beginning. I bought the Rotel for €20 2nd hand. Brought it home, plugged it in and nothing happend. Stil had the power button on and after a couple of minutes I suddenly heard the relay clicking, there was something alive. Only clicking, no display. Decided to open it up and have a look. Thought about protection mode so pulled the different components one by one. When i disconnected the cable from the digital board, the relay “connected” and it stayed on. Plugged it back in it started clicking again. Only one time i plugged it back in and the dispay went on and of with the clicking of the relais. The frequenty of clicking slowed down and all of a sudden it was on! Connect some old soeaker to it and it actualy produced sound as well. Turned it of and since that moment, back to where I am now, nothing, only the relais clicking. I’ve put in new capacitors in the power supply part, since the clicking slowd down and when I pulled the digital board I thought that maybe the caoacitors where faulty and couldnt supply the demand.. after that I posted the topic start, did the thing you thought about and thats the whole story..
I initially thought that excessive DC offset was the likely problem, but now doubt that's the cause. I'll study schematics and try to devise tests to diagnose.
Thanks for your patience.
Thanks for your patience.
Do you have the remote control? You might peruse the owner's manual, attached below. There might be some configuration in which the remote has dominance--- I'm uncertain about this.
I find it difficult to follow the schematic and the scant info, but haven't given up. There are several signal labels with intriguing names at the microcontroller. My plan of attack is to find the associated circuits, thinking that one of them is causing the controller to block power-relay activation. But it's very tedious trying to locate the corresponding circuits.
Though I doubt it's the cause of the problem, if you wish to explore the DC offset error, measure the voltage across RL212 (and its brothers in other channels). Ideally, it should be 0V but only 10mV or so could explain the excessive offset. (This measures the leakage though CL206.). This may not be offset cause, but it's easy to explore.
I find it difficult to follow the schematic and the scant info, but haven't given up. There are several signal labels with intriguing names at the microcontroller. My plan of attack is to find the associated circuits, thinking that one of them is causing the controller to block power-relay activation. But it's very tedious trying to locate the corresponding circuits.
Though I doubt it's the cause of the problem, if you wish to explore the DC offset error, measure the voltage across RL212 (and its brothers in other channels). Ideally, it should be 0V but only 10mV or so could explain the excessive offset. (This measures the leakage though CL206.). This may not be offset cause, but it's easy to explore.
Thanks for the reply again and sorry for the late reply! Will look into the OM, thanks for that.. I’ve measured (from pole to pole) the RL212 and his brothers, all 0-1 MV so that looks alright!? Very curious about your attack plan and your findings.. please let me know…
I'm on vacation tour, so I've not been able to devote much attention.
At present, the amp will not start at all unless you unplug CP553. With CP553 unplugged, the relay "clicks." Does the relay close and stay energized, or does it cycle on and off? If relay is cycling, about how often?
At present, the amp will not start at all unless you unplug CP553. With CP553 unplugged, the relay "clicks." Does the relay close and stay energized, or does it cycle on and off? If relay is cycling, about how often?
It doesn’t stay closed and energized, it just clicks with 1 sec intervals.. no display or anything.. also fugured out that when I keep CP553 connected and disconnect CP551 from the digital board it also clicks the same way…