CDM12.4

I have the CP-ROM of which I bought from China. Interested to know the problem and interest to know how to improve it. DO not really like the result. After reading the diagram, I still do not know what is the problem, May be I am not on the digital domain, can KK explain it in more details. Thanks.

Unfortunately, my digital knowledge is so so ..... anyway, if there is a course to modify the CDM 12, I will certainly the first one consider to join.

KK,

Can i confirm that the bug come from 74HC04 instead of SAA7824. I just look at the CD-ROm today, they are using SAA7327.

Thanks.