Is My Player's Clock 12.288 Mhz?

[dantwomey]

I've had the cover off of my new universal player in anticipation of installing a new precision clock and after a brief look around the only crystal I could find was on the main audio board and was marked 12.288/32. I've since received a copy of the service manual for this player and the first instance I can find of any sort of clock is labelled 12.288 Mhz. This causes me to pause and take note that all the previous replacement clocks I've seen do not mention this frequency. Thoughts anyone?



Regards,
Dan

[Lars Clausen]

Hello Dan

Yes this is indeed a 12.288 MHz player.

Best regards

Lars Clausen

[dantwomey]

Lars,

None of your Audio Reference Clocks carry this frequency:

Frequencies of:
11.289600 MHz
16.934400 MHz
22.579200 MHz
24.576000 MHz
27.000000 MHz
33.868800 MHz
45.158400 MHz

Can I assume that one possible option would be for me to purchase one of your clocks and then swap the 12.288Mhz crystal from my player for the 11.289600Mhz one? Or, would you produce a 12.288Mhz Audio Reference Clock just for me?

Regards,
Dan

[Lars Clausen]

I have already ordered 12.288 MHz crystals, they should be available shortly.

[Extreme_Boky]

Hi Dan,

This is probably for your DV7600…

DSP chip uses 12.288MHz frequency to generate various other frequencies for different sections in a DVD player, like video section, transport servo section and audio replay from DVD-A, CD (and SACD?) disk section(s). This chip contains dividers / multipliers and it also does clock signal squaring, buffering and clock distribution.

External 12.2888MHz clock source would help a lot. If you can't find the clock with 12.288MHz crystal, you can buy any clock and replace the stock crystal with a 12.288 crystal you removed from your DVD player. There is one important thing to check, PIN 127 clock signal amplitude - use a CRO with probe setting at 1:10 to prevent clock signal load, which could give you funny signal shape... It won't be bigger than 3.3V (!!!) so you'll need to choose the external clock accordingly!

Good luck,
Boky

[Lars Clausen]

Just to let you know, we can now deliver 12.288 from stock.

[WTS]

Hi,

What kind of DVD video picture quality improvement can be expected from changing out the clock osc to one of your units.

Thanks