Super Cdrom2 Interference. RF Shielding?

[benlefou]

Hello all.

I'm having an issue with my Super Cdrom2 unit. I'm getting some kind of interference on my monitor when the unit is attached to my Supergrafx. Here is a video of the issue:

When I remove the CD-ROM unit the interference goes away. Now I recently had my CD-ROM unit re-capped, the guy who re-capped it removed the RF shielding because it was a bit rusty, do you think this is the cause? And reinstalling the RF shielding will fix it? I believe it has to be soldered on? Is this pretty straight forward to do as I have basically no soldering skills.

Any help is much appreciated. Thanks.

[thesteve]

the sheild is as simple as line up the tabs and solder down
couldnt see the issue on the vid

[benlefou]

Thanks, I managed to put the Shielding back in, and at first it was fine again. But this morning the interference is back?

It is best seen on black  backgrounds, its like a snowy effect, little dots and lines jumping about the screen. Maybe an issue with the power supply? Running the Supergrafx is fine, but if it's connected to the CD-ROM unit then the interference is  there?

[ApolloBoy]

Maybe an issue with the power supply?

What PSU are you using?

[Vimtoman]

What type of video driver do you have.
Is there shielding in the scart cable.

As ApolloBoy asked what wattage is your PSU

[benlefou]

Not sure about the video driver? How do I find that out?

The cable has shielding.

And the power supply is this one:

http://en.retrogamesupply.com/collections/pc-engine/products/power-supply-all-in-one-for-nec-pc-engine-supergrafx-super-cd-rom2

[Vimtoman]

The shielding is there for shielding:)

There are pads that join the Gnd plane in various positions on the pcb.

The shielding would normally join these sections.

I'm guessing that he bridged the unpopulated pads to complete the circuit that the shielding would have made if in.

Might be a good idea to check this.

They are numbered with a J notation J1 , J2 etc and are usually at the edge of the pcb.

[thesteve]

is the noise cd dependent?
most noise in the duo is caused by the cd drive drawing pulsed power

[benlefou]

It's not dependant on the CD because it's there when playing hucards.

It must be the Power cable for the CD ROM unit. Running the Supergrafx off its own cable is fine, as soon as I plug the CD ROM unit power cable in the noise appears! What are my options here?

Do I need to try and source an original power cable for the CD ROM? It's driving me crazy!

[thesteve]

its the same supply as the duo

[benlefou]

OK thanks for everyone's input. I have now resolved the issue. It was indeed an issue with the generic switch power supply.

After a lot of trouble shooting and testing I realised it had to be the psu, after digging through my box of spare cables I found an old Sega psu which could be used (non switching) and it works like a dream! No noise/interference at all! I can now finally play Nexzr! 

[unclebugspayton]

The steve, super cd and duo are not the the same power supply.....super cd is 12v 1amp neg to pos....duo is pos to neg 10v 1amp.

[mickcris]

while they do not have the same exact voltage spec, they are interchangeable.  the 2v does not make a difference.

gamedrhk sells one that works fine that is only 9v
http://gamedoctorhk.com/index.php?main_page=product_info&cPath=69&products_id=816&zenid=t8h34v87rolg2ulplkkah6tur0

[thesteve]

another point on the stock super cdr2 supply, its 12V 1A @ 100V input
so at 120V input thats 14.4V out and the regulators start getting hot