Need help: Defective Xevious and Desert Falcon PAL cartridges?

[Mister-VCS]

Same problem with both games: graphic glitches and flickering at the beginning of a new game -and then both game crashes! What is going on here?

Both cartridges look clean and my PAL 7800 works fine with Asteroids and Galaga.... Both games are from the UK (PAL).

 

 

Xevious (locked up)

[+Mitch]

Do they have the "P" sticker on the back? They could be NTSC carts that someone sold you.

 

Mitch

[Mister-VCS]

Do they have the "P" sticker on the back?

Mitch

 

Yes- very sad, because especially Xevious should be a fun game...

[Blue Azure]

Check the edge connector with the fingers on it (not necessary to open the cart). Use a cotton swab with alcohol and sweep across the fingers and leave cart to dry for a while. Re-insert and, et voila, 95% sure this will fix the problem.

[Mister-VCS]

Check the edge connector with the fingers on it (not necessary to open the cart). Use a cotton swab with alcohol and sweep across the fingers and leave cart to dry for a while. Re-insert and, et voila, 95% sure this will fix the problem.

 

Thanks- but my carts are in the 5% zone...

[Blue Azure]

That's what I kinda thought. Strange looking graphics I've never seen before. But it is these specific carts as the others are working, so it sounds like your 7800 machine is working right. Are these EPROM-based carts (do the cart labels look "normal" or homebrew?)? Maybe try opening one (there's a screw under the label if there is a label), and then reseat the chip, if possible. May need a soldering iron for this one.

[Mister-VCS]

Ok - tried another Xevious-cartridge- same effect. Could it be a RAM-defect in 7800 mode? Could I switch RAM from a NTSC 7800 into my PAL 7800? How to identify the bad RAM?

What to do??