Naim Audio CDI CD-I CD1 CD-1 CDS - only impaired Skip > Operation
 

since more than 15 years I am not able to find this incorrectly behaviour by pressing the ">" button.
The player works fine in all other functions.

Only by pressing the ">" button (skip next) I observe an odd behaviour:
The arm starts strong to vibrate and goes several times the way from start to end and again back.
During this period and thereafter no commands trigger any response (even not "stop").

Only after switch off and again switch on - the player works fine by all CD's, and CDR's as long as I press only start. Amazing for me is, when I press "<" button, I observe also correct operation behaviour. The replace of the power amp (buffer stage) IC for tracking servo section and the associated electrolytic caps released no changes in the error image.

By replace (interchange) step by step all PCBs with help of a second model I was able to limit the error to those PCB, where the MCU is inside (mask programmable version from Motorola, type No ZC99685P), because this error went along by exchange this board in the second "CDI" exemplar.

I have forget some details in the meantime, but I will now risk a second service task.

Therefore I want to know at first a Philips/Marantz cd player or cheap hifi system/ghettoblaster/car-radio model, where also the ZC99685P from Motorola is in use as operating MCU (ZC99685P was custom made for Philips/Marantz but wasn't custom made for Naim Audio).

Who know that ?

BTW - are there other user's with the same unwanted effect as described above ??
I haven't read helpful advices about follow threads:

NAIM CDS-1
TDA1541A
http://www.diyaudio.com/forums/digit...io-output.html
http://www.diyaudio.com/forums/digit...placement.html
http://www.diyaudio.com/forums/digit...x-s-laser.html
http://www.diyaudio.com/forums/digit...-naim-cdi.html
http://xing-v.blog.163.com/blog/stat...1171024718735/
http://xing-v.blog.163.com/blog/stat...1720103352480/

Thank you very much for helpful advices.

Maybe I have find out other cd player models from ROTEL with same custom made user processor (at least according the Service manual from hifi manuals and some websites from China):
1) According Service Manual of the RCD-865BX I read by U108 follow: MC68HC05C8/P110 (ZC99685P) Part No "088 44021"
2) According Service Manual of the RCD-965BX I read by U108 follow: MC68HC05C8/P110 Part No "088 44021"

Some questions rises up:
1) Why is the "ZC99685" set in brackets by the model 865BX ?
2) Why is the "ZC 99685P" not at all mentioned by the model 965BX ?
(according the URL
°Ë¸çÀÖÀÖ ÒôÏìDIY - Powered by Discuz! Board
the "ZC 99685" is in use)
3) What is the main difference between the MC68HC05C8/P110 and the ZC99685P (maybe EEPROM vs. mask programable version ?) ??

Best thanks for advices.

schematics and part lists of both Rotel models:
Download the Rotel RCD-965-BX service manual for free - Hifi Manuals
Download the Rotel RCD-865-BX service manual for free - Hifi Manuals

no informations concerning differences between the MC68HC05C8/P110 and the ZC99685P ??

Would you be so nice and check transformer windings for me if when you have CDI on your bench again? Or maybe you have a schematic for it ? I have NOS power transformer for CDI and it would be cool to know how those transformer sections are arranged. Maybe I build outboard PSU for my old Arcam Alpha 5. TIA , L

I haven't this model currently on my bench. For checking and classifination the appropriate primary windings you need the R-DC values of all winding parts.
After connecting with the mains you can measure all secundary VAC values (condition: no-load operation, i. e. without secundary load).