Sega Nomad with modern LCD and region switch colour fix

[omp]

Hello chaps

Thought I would put this up as I haven't seen it around (doesn't mean it isn't I suppose lol).

Start of story-
For my birthday, wife asks what I want. Answer I would like a Nomad! (for modding of course). They are expensive in Australia, so I sourced one from America.

I also want it fitted with a LCD screen and region switch.

I planned (and I do expect to be criticized) from the start to have my region switch as a manual region switch (AU, JPN, USA), rather than pressing mode etc as some PAL games aren't keen on that sort of thing (screen scroll/flash etc)

Anyway I got the Nomad and LCD and I knew if I did the mod I would be visited by the black/white screen fairy. Had a few chats with TmEE about it and gave me the general idea.

I installed the LCD screen and initially I locked the video encoder with a 4.43(blah blah)Mhz 4 pin oscillator. The screen I got worked, buuuutttt I wasn't keen on the look of PAL60 (US and JPN region), the images seemed to have a "ghost" image around them, making it looked slightly smudged. When the switch was set to AU (PAL) the image was fine. Perhaps the LCD monitor, whilst being ok with NTSC and PAL(50) wasn't 100% happy about doing PAL60.

Anyway I got to work about re-wiring it all up so that the standard clock would do it's thing while the added oscillator would do the other thing.

First pic is where you can disable pin 6 to the CXA1645 video encoder, you could lift the leg if you want to but this is MUCH easier and safer. Also shown is where you can grab GND and +5V for the oscillator

NTSC clock and power points.JPG

Oscillator as shown, grab the datasheet for what you need.

4.433619 oscillator.JPG

As above but wired up and partially insulated. I put this in the front half of the case under the A,B,C,X,Y, Z buttons, really no other place to put it. (I also wrapped it in electrical tape for insulation)

oscillator wired up.JPG

CXA1645 video encoder, disable pin 7 up the line as shown. +5v selects NTSC mode, GND gives you PAL mode. Jolly interesting to note that it pulls itself high (+5V) when not grounded, so you only need to switch in GND! Pin 6 is for clock signal.

video encoder.JPG

Switch schematic, quick ACAD drawup of the switch I used which is a 3 position 4 pole switch (slide)

Switch fix-Model.jpg

[omp]

Continuing

Region switch left is JPN, middle is USA and right is AU desoldered the contrast wheel for the old screen and squeezed the switch in there. Now I know folks won't be keen on this but meh.

region switch.JPG

LCD menu buttons. Probably didn't need to do this, but I did. If I didn't do this there would be no holes drilled in the case.

lcd menu controls.JPG

PAL Ghouls and Ghosts

Pal G&G.JPG

NTSC (USA) G&G

USA G&G.JPG

NTSC (JPN) G&G

JPN G&G.JPG

I am quite happy with this, I have also done the cam-corder battery mod, works a treat.

I hope that if anyone else can use this guide it will help.

[raylyd]

Any way of doing this with sebs code as i love that sebs code no extra switches.

but cool to mod my two i just got today.