Nintendo DemoBoy II Questions. I have one now, but I don't know how to use it?

[DistantStar001 | 3]

As the title says, I recently obtained a Nintendo DemoBoy II but I don't know much about it.  I tried asking the good folks at AtariAge, but was recommended to ask here.  So here I am.

I understand that it was used to connect an original Gameboy to an external monitor for demos and store displays.  However, that's about all I know.  I've tried looking this up, but there doesn't seem to be very many of these out there.  As such, there doesn't seem to be much information to find.

When powered on, It puts out a picture (orange and green with a boarder), but I have no idea how to connect a Gameboy to it.  This one seems to be able to connect two GameBoys, and has outputs for two screens, but would I need a connection cable for two player games?  Is there any advantage to this over the Super Gameboy for the SNES?

Also, I have no idea what it's worth?  What its specifications are?  If it can be used with other Gameboys (Pocket, Color, Advanced, so on)?  Or if it can be interfaced with other non-Nintendo portable devices (SEGA or Atari)?    

Basically, I have this new toy now and I have no idea how to use it.

[360collector | 289]

very cool. Looks easy to open up just a few screws, why not look inside?

[Tanooki | 4,934]

Thanks for popping by.  I hope someone here can help, it was the best environment I could think of on a forum that would have a chance of an answer.  If this fails, not sure other than something fairly large like multiple reddit groups where you may get lucky.

I did see this with multiple shots of both the outside and inside.  I think you're missing some ribbon cable that goes between the GB and the unit itself.

https://consolevariations.com/variation/kiosk/nintendo-demo-boy-ii

Picture 8 shows it, but 12 also shows it goes into the back of the GB under the battery door snap, so not sure if it's soldered in or some weird jumper hiding inside.

Well known in the coding/emulation circles Chris Covell covered a variation of this called Demo Vision, looks quite close to what you have too: https://www.chrismcovell.com/demovision.html

THis has some incredible shots of the inside of your unit, site is in spanish if you can't read it, google translate it:

https://www.elotrolado.net/hilo_demo-vision-y-demo-boy-2_2456417

[DistantStar001 | 3]

Thanks for the responses so far.  It appears that most of this Information confirms what I already know.  And there are some good pics of the interior of the unit.  From the looks of it, the unit is compatible with both the original DMG as well as the Pocket.  However the Gameboy needs to be modified to do so.  Unfortunately, there doesn't seem to be a clear image of the modification. 

So far, this video gives the best image I've found:  

 

At abut 8 and a half minutes in, he shows a clear image of the solder points for the Gameboy Pocket.  Unfortunately, the wires are a bit too twisted to make out the pinout on the connector (aside from pin 1).  Still, it's a start.

 

[Deadeye | 1,596]

I believe @retroUSBhad one and sold it recently.  He doesn't stop by often, but maybe he has some pointers. 

[nrslam | 476]

Please post whatever you find out here. I've had a similar looking system, a Demo Vision, for years and could never use it as it came without the cable or modified GB. Yours looks to be in much better condition.

 

[DistantStar001 | 3]

Know it's been a while, but I finally got the pinout/solder-points to hook a GameBoy to this thing!  Thanks to the FaceBook Nintendo Collector's group.  Haven't tried it yet though...