Home Built RGB Monitor

evildragon · Post by **evildragon** » Mon May 07, 2007 4:40 am

Well well well, I can't believe this actually worked!

I had an old NTSC monitor, and it had such a nice picture tube, I wanted it to be RGB.

Little did I know it was SO easy to pull off!

On the neck of the CRT, there are a bunch of wires going to it.. 3 of them are R, G, and B.. So, I spliced those, connected it directly to the Genesis.. Well, I knew at that point, I was still lacking one thing, the Sync.

So, since the H/V was still hooked up to the motherboard of the monitor, I hooked up the Composite video to the Composite video in jack.. This essentially just took the H/V sync, and it worked.. A nice RGB picture on the monitor.......well, almost..

The picture came out a little too bright, so I had to adjust the R, G, B CUT values on the neck.. A resistor probably was all I needed, 75Ohms to ground, as I essentially did bypass all that circutry.. But I was in a rush..

Daaaannnnggg, RGB is awesome! Too bad I can't do this mod to my HDTV, that will still need the RGB to Component adapter..

TmEE co.(TM) · Post by **TmEE co.(TM)** » Mon May 07, 2007 5:26 am

I haven't tried to do that ... I don't like messing with monitors and TVs, high voltages... but my TV has RGB input so there's no need for me to start modding my old SVGA monitor

evildragon · Post by **evildragon** » Mon May 07, 2007 5:33 am

TmEE co.(TM) wrote:I haven't tried to do that ... I don't like messing with monitors and TVs, high voltages... but my TV has RGB input so there's no need for me to start modding my old SVGA monitor

lucky you XD anyways, this won't work on computer monitors, only TVs with Composite Video-In... It uses the Composite Video as the sync (heck, feeding the Composite video jack just Comp-Sync might actually work)..

here's some pics.. my camera died.. knew the damned thing was on it's last leg, so this is webcam shots, but they do show justice.. as on NTSC or PAL, those trees would be fuzzy, and not as sharp as they are..

TmEE co.(TM) · Post by **TmEE co.(TM)** » Mon May 07, 2007 7:35 am

It would work, because MD outputs RGB with H and V sync that SVGA monitor needs. Only progblem is Hsync which is 15KHz, it needs to be doubled somehow(PC monitors like to get 31KHz). I've seen one monitor that accepted 15KHz Hsync, but it isn't mine...

evildragon · Post by **evildragon** » Mon May 07, 2007 12:17 pm

TmEE co.(TM) wrote:It would work, because MD outputs RGB with H and V sync that SVGA monitor needs. Only progblem is Hsync which is 15KHz, it needs to be doubled somehow(PC monitors like to get 31KHz). I've seen one monitor that accepted 15KHz Hsync, but it isn't mine...

that's what i meant.. they won't sync to it.. and it would be rare now too find one..

MERLiX · Post by **MERLiX** » Tue May 08, 2007 11:49 pm

I could kick myself for this. I left this pc back in England, when I moved to the USA.

So in England I had the megapc, it was basically a 386 motherboard, with an isa card which contained an adlib card/megadrive unit, with a cartridge slot on the front. The monitor that came with it had a special mode it would flip too, you could here the frequency change when you slid the slider over. The monitor would normally display a max of vga (640x480), and the megadrive video mode would be fine except it would crunch the last 2-4 centimeters on the right together like it didnt have enough to fully do a x2 for the video.

Being pal, I know the monitor was running at 50hz, but I couldnt tell you the other frequencies though.

Oh and the RGB looked so crisp just like your screen shots.

Could still kick myself for leaving the little guy there (it was a really small foot print and would have been a fun hack job to try and use it in a new pc,, so short sighted of me)