ARCHIVED FORUM -- March 2012 to February 2022READ ONLY FORUM
This is the second Archived Forum which was active between 1st March 2012 and 23rd February 2022
Hi everyone,
Need some help to solve a problem:
After a randomly listening time , sometimes one hour sometimes half hour and so on, the right channel output goes down. Power off for around 10 minutes , on again and playback is normal. And repeat.
The normal issues known , solved. Griplets done, reed relays replaced and the symptom still present.
Any idea where to look on?
Thank you
Did you re-cap the decoder board while you were dealing with the "usual suspects"?
I allway's replace all the electrolytic caps on that board from past experience,it's worth the effort.
There are twin dac's in this design of course,so pay particular attention to the soldering around these devices.
Good luck with the repair,the great performance from these machines is the reward for your tlc
Regards,
Nick
Thank you for the reply.
Yes I replaced all caps around DAC's and opamp's.
Still same problem.
Noticed new symptom.
If I go up with the volume only on that channel, the music is audible in the tweeters very very low and if put the player in "stop" mode and again in"play" for a few times the sound goes normal but I can hear the click of the relays in speaker. On the left channel everything goes normal.
So, the DAC works , since I can hear music. So the problem could be between the DAC output / input to op amp.
Today I will do the NOS mode and I will try to "steal signal" directly from the first op amp output.
Might seem a daft question,but have you checked that all the cables between the CDX and the amplifier are ok?
Have you tried reversing the connections to the amplifier to see what happens?
Might be indicative of where the problem is.
The DAC ic's are very reliable in my experience,but...
Do you have an oscilloscope etc to trace the missing signal?