PE-Duo huecard working but no picture from cd unit. *Solved* almost

[NichlasEk]

Edit3: so i dug in to the cd section a bit more. I removed both BA chips after finding a short to ground. Turned out to be a hairline tinwhisker to one of the new caps. Stuck the chips back and fired it up. The laser now returns to the ready position, i can also see the red light from the lens.

Tried to callibrate it, but to tired. Onward and upwards!.. tomorow.

Edit2: I Took of the plastic cover for the cdrom. One of the ribbons to the laser was severed. Luckely i had a spare laser mech. However i get the same symtom with the new mech
The laser lights up when i press run. But no movment from the spindel or other motor. Both check fine with a battery.

Could it be the focus coil in the new laser? I dont know the init seqvence for the cdrom unit. Maybe a helpful guru could give me a hint?

Or should i look at the big BAXXX chips? Seems like controller chips with mosfets or powertransistors.


Hi! Thanks for a very informative forum.
I bought a junk PC engine duo from yhaho japan.

Edit: after changing to a new better cable i get a picture in cd mode. But still with sync dropouts.

The image stays at pleas wait a moment after pressing run.
The laser lits up but the cd wont move a bit and the lens wont try to focus. I have tried the pots but no luck.




I recapped it with a kit from console5.
I had trubble getting it to sync with hu cards
And ended up gerting sync on luma (pin40 on video dac)

With this it works with my OSSC and kind of with the TV.
I get sync droppouts and mild distortion from unclean sync.
But with c-sync and sync on composit it wouldent work at all.

I have checked all cappes twise and tried to check countinuity on all the vias and traces i can.

Still no luck with CD mode. No sync and no spin without huecard. If i close the lid switch and press run i get a lit LED and a increase in current draw. But no picture.

Any idea where to start?

Thanks again /Nichlas