PCEngine-FX.com

Hi,
I received a PC Engine Duo for a repair and mod.
According to the owner the console doesn't play cards or CD and a capkit might be needed.

When I tested it the first time, cards played fine but in CD mode it was stuck on a static, plain white screen (like when a normal PCE is switched on with no card).
With the help of a logic probe I found a floating address line on the BIOS ROM. I patched it with a piece of kynar wire and the CD mode was restored:

(http://img11.hostingpics.net/pics/908068DSCN4639.jpg) (http://www.hostingpics.net/viewer.php?id=908068DSCN4639.jpg)

(http://img11.hostingpics.net/pics/511406DSCN4657.jpg) (http://www.hostingpics.net/viewer.php?id=511406DSCN4657.jpg)

It as time to test it with a CD: nothing, the CD doesn't even spin, sign that the lens doesn't 'see' anything. So I installed the capkit (quite a lot of caps) and... No change.
The owner ordered a new lens and once fitted the console now recognises disc, sometimes I can see an error screen with a game and I can enter the audio mode with a normal audio CD but nothing more (no tracks data, length, etc.):

(http://img11.hostingpics.net/pics/472434DSCN4663.jpg) (http://www.hostingpics.net/viewer.php?id=472434DSCN4663.jpg)

The owner pointed me to 2 different threads explaining how to adjust the pots. I carefully took measurement of each one before starting the job and followed the instructions carefully.
But still, CDs aren't read properly.

Does anyone have an idea at what to look?
I'm not really specialised in PCE, I've just bought one few weeks ago, 18 years after having sold my duo!

Thanks for your help.

I adjust all mine by ear so I can't give you any values. I've just done it so many times I can tell by sound when things are set up correctly or not. V101 is the lens positioning. V102 and V103 have to do with lens gain. V104 and V105 rarely ever have to be adjusted so I'd leave those alone. V104 is spindle speed. Can't remember what exactly V105 is for sure. I only try that one if nothing else is working.

You have more floating addresses or that jumper wasn't quite right........checking

Jumper is correct

Data from cxd1167 to ic501 missing

Quote from: thesteve on 12/02/2016, 12:53 PMData from cxd1167 to ic501 missing

Thanks.
You mean faulty cxd1167/ic501 or another broken trace?

Could be a bad chip, but it's generally an open trace