Hi everyone.
I have been working on my Marantz CD16, adding a trichord digital output board and power supplies. Here's a pic of the work in progress:
I'm going to shorten the clock leads when I mount and connect the DOB outputs.
However, at the moment I have a rather odd problem arising. The player works fine when first powered up, but within 15 minutes the DAC (modified M-Audio Superdac) starts losing data lock intermittently and then completely, and then the transport mechanism goes haywire. Switching the player off and then on again sorts it out for the next 15 minutes.
Any ideas as to what the problem is? Could it be injected noise on the power supply (as I've seen some 33.8688MHz carrying along the DOB power supply connections)?
Any help gratefully received!
I have been working on my Marantz CD16, adding a trichord digital output board and power supplies. Here's a pic of the work in progress:
An externally hosted image should be here but it was not working when we last tested it.
I'm going to shorten the clock leads when I mount and connect the DOB outputs.
However, at the moment I have a rather odd problem arising. The player works fine when first powered up, but within 15 minutes the DAC (modified M-Audio Superdac) starts losing data lock intermittently and then completely, and then the transport mechanism goes haywire. Switching the player off and then on again sorts it out for the next 15 minutes.
Any ideas as to what the problem is? Could it be injected noise on the power supply (as I've seen some 33.8688MHz carrying along the DOB power supply connections)?
Any help gratefully received!
The transport spinning out of control is usually a sign that there's something wrong with the clock feed to the decoder (the SAA7350 here).
Check your black lead is connected to a digital ground point common to both the DAC and decoder digital grounds.
Do essentially the same for the red lead: trace the clock routing to both the DAC and the decoder chips, and see if they are fed by a common inverter. Then either run two new feeds (twisted pairs) from the trichord to the correct (Xin and digital ground) pins on both chips; alternatively feed your new clock signal just to the inverter on the board doing the distribution -probably the more reliable option, in case there is anything trick in the Marantz implementation about relative timings of the clock signals.
If you run your new clock in direct, make ure you cut the traces for anything else 'upstream' so that existing inverters do not load-down or fight the new clock feed.
Good luck!
M.
Check your black lead is connected to a digital ground point common to both the DAC and decoder digital grounds.
Do essentially the same for the red lead: trace the clock routing to both the DAC and the decoder chips, and see if they are fed by a common inverter. Then either run two new feeds (twisted pairs) from the trichord to the correct (Xin and digital ground) pins on both chips; alternatively feed your new clock signal just to the inverter on the board doing the distribution -probably the more reliable option, in case there is anything trick in the Marantz implementation about relative timings of the clock signals.
If you run your new clock in direct, make ure you cut the traces for anything else 'upstream' so that existing inverters do not load-down or fight the new clock feed.
Good luck!
M.
Please take the advice of Martin Clark. That is the correct way of connecting a new clock line.
Empirical testing and/or working without schematic can be dangerous for the health of your CD16.
http://www.triodedick.com/cd_klok.htm
Empirical testing and/or working without schematic can be dangerous for the health of your CD16.
http://www.triodedick.com/cd_klok.htm
It's working fine now. I had it almost right first time, but the clock line wasn't quite right. I don't have the schematics atm, but tracing the circuit and the pinout of the inverter gave me enough.
An externally hosted image should be here but it was not working when we last tested it.
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