Portable n64 screen just flashes

Hello, I've built everything and put it all together into a case. But before I had it in the case I put together all the wiring and it played the n64 on the gamecube screen perfectly. Now for some reason when i turn on both the gamecube screen and n64, the gamecube screen flashes and thats it. I tried pluging the n64 into another tv, turned it on and it played normally, then with the n64 turned off I pluged a gamecube into the gamecube screen and it played normaly. Ok now is the part thats bothering me when I turn on the n64(still pluged into a different tv) it plays then I turn on the gamecube and gamecube screen, the gamecube is playing on the gamecube screen but the n64 on the other tv goes black but the light on the n64 is still on. I've checked my wiring more than 6 times but still can't find out what I did wrong. Any ideas?

I'd just buy a portable N64(L64 FYI)

Post up pics so I can understand better

Do you know a place where I could purchase one? Here is a video I made of the problem. http://www.youtube.com/watch?v=T33u8zhtXic And here is the picture of the wire diagram I used.

edit: Ok I found out what my problem was. The reason I was using those adapters was because I thought the batteries in my 8 batterypack (as you can see on the diagram) were dead so I replaced it with a 12v. adapter, but my batteries weren't actually dead; The springs on the negatives of the 8 pack were all bent in and not all of them were reaching the batteries so I took off the 12v. adapter and replaced it with the 8 pack and rolled the batteries around pushing them up and down until the n64 turned on. And surprisingly my game started playing on the portable tv. But I still wonder why the adapter didn't work.

I was being an idoit... L64 is homemade, and it can't be bought

Thats good.
Your video was... I couldn't understand it....
But, I'm glad the problem was resolved

You should try to get a TFT screen on there and mod the N64 box to make it fit.

Ok. Without thinking moneywise would a Samsung Q1 7" Ultra Q1U-V (Intel A110 Processor, 1 GB RAM, 60 GB Hard Drive, Vista Premium) be better with an n64 emulator or should I get a new n64 or should I get that other thing? Cause I've been getting too frustrated putting this together and some cords popped off and I put them back on and now all the n64 does is make a low tone so I think I fried it.

LOL, I did that to my DS, Nintendo sent me a free one though

I would say, try to get this to work, so obtain 3-4 N64s, and if you get this working, try to get it working with a PSP's TFTLCD Screen.

You can find a portable N64 screen and use that and skip the hardmodding too.

Hey thx for the info. I found out I actually didn't fry anything so now I have two N64s. What went wrong was I was using to thin of cords and they just wore out easily so I just hotglued all the wires directly into the the back of the n64 and now it works and it's all put together and also I just finished my battery charger and that also works. But is there a tutorial site for converting a/v outs like that TFTLCD Screen? Cause I'm not sure what to type into google cause when I did try I got this "convert avi to mp4" stuff. The TFTLCD Screen is smaller than the portable gamecube screen, does it have better quality or somthing?