CDX / Multi-Mega shielding question.

Hi friends. Yes, it’s another sob story. This is regarding a PAL Multi-Mega purchased from fleabay.

Won’t bore you with questions on how to fix the laser (aye it needs sorting).

Opened up the Multi-Mega and discovered there was no copper shielding. All traces/signs of it completely gone. So presumably it’s been chucked.

The resistor that should (?) connect board to copper shielding is now fixed completely to the board (see pic).

[GALLERY=media, 2676]73FB5713-AE6B-46FB-841C-E2AA442912E1 by SwedishSonna posted May 1, 2018 at 11:17 PM[/GALLERY]

Question 1: Can I operate the console without the shielding, or do I need to find a solution to replacing it?

Secondly, the plate between the cart and CD board is missing its screws. So the CD board and this metal plate are floating and not fixed.

[GALLERY=media, 2677]C41783A3-28F7-44FE-B408-4332FB9FDB52 by SwedishSonna posted May 1, 2018 at 11:17 PM[/GALLERY]

Question 2: Could somebody please recommend any particular screws to use as substitutes here.

The console was a really decent price. Carts work fine, outputs a signal fine, caps look good etc. Just doesn’t play any CD’s and missing a few bits.

Would really appreciate if anyone could offer any advice or suggestions. Cheers.

 

Hi. I've worked on a few CDX and Multimega units.
They can work fine without the copper shields if that resistor is linked to ground, and I've done this when they are de-cased on the bench, but not recommended for the long run. Perhaps a replacement material can be made.
The laser probable needs replacing. look for a Sanyo-SF-C93AQ. eBay usually has a few listings, but some may be used.
Then the pots might need adjusting for a new laser to pickup the CD. Done this a few times too lol.
As for the screws, you can probable experiment with some small screws if you try them carefully. I'm sure you wont need them all, just 2 or 3 to hold it in place.
Good luck, the Multi Mega is a great little console

 

Hi mate. Thanks a lot for the reply. I'll see if my Mega Drive has any donor screws I can use.

I think there are some pot values on sega-16 I can try using. I know it ain't one size fits all... But it's worth a shot. Failing that I'll try a new laser.

As for the copper shielding, maybe I can try the sort that has the adhesive backing (but not peel it off..) I'll have a look at more teardown pics/vids to see exactly where it connects up to

 

I did a google search for "plastic coated foil" and some of the products look like they might work.

 

This system is really suspect… Was it an eBay purchase? It makes me furious to see all these with missing bits and sketchy servicing for sale nowadays. I've been opening up CDX consoles since the early '00s and you would *never* see stuff like this back then. This is a direct result of the greedy and inexperienced trying to do mark-ups / flipping.

Anyway, you're going to need some pretty small machine screws for those holes. I imagine they are something like M1 .5. The copper shielding is optional, and is mostly used for heatsinking and noise reduction. You would be mostly okay without the shielding as well, though I guess you do risk your system overheating if you leave it on for days.

I wouldn't bet that your problem is just the laser. When I see systems like this that have been tampered with excessively, they usually have other issues with playing CD games.