Author Topic: Sega sg 1000II (Read 2266 times)

trol · « **on:** October 06, 2003, 03:23:27 am »

My Jap Sg1000II doesn't work om my European tv (duh...).
the computer only has an rf output, I tried a euro rf modulator, the sound and picture are good, but it's in black/white.
On the pcb there are some marks: r ,g, b, csync and vQ0.
I hooked the r, g,b and csync on a scart connector, but that did not work.
I only got a black screen with runnig lines, still in B/W.

Can anyone help me? :blink:

Lawrence · « **Reply #1 on:** October 06, 2003, 03:33:45 am »

This page has instructions (in Japanese) for making an RGB amp for this system:

http://www.h5.dion.ne.jp/~baku/RGB/SG-1000...1000II_RGB.html

Lawrence.

trol · « **Reply #2 on:** October 06, 2003, 04:05:48 am »

Allright! Thanx alot

trol · « **Reply #3 on:** October 06, 2003, 06:32:55 am »

Damn, no schematics.
Has anyone built this before?

trol · « **Reply #4 on:** October 06, 2003, 07:27:30 am »

According to tha japanese site, the rgb signal inside the sc 1000II is 1.4vp-p What does that mean?
Will a 'standard' rgb amp do the job?

Lawrence · « **Reply #5 on:** October 06, 2003, 11:44:07 am »

1.4vp-p means, when looking at a sine-wave representation of the RGB signal, the max voltage level is 1.4 volts peak-to-peak (the tops of the wave). VGA uses, IIRC, 0.7v p-p, where SCART or arcade PCBs use (And I'm probably wrong here) 1v p-p.

In fact, I'm sure I'm wrong, forget the numbers I gave, but "1.4v p-p" means 1.4 volts peak to peak. =)

Lawrence.

trol · « **Reply #6 on:** October 19, 2003, 05:37:49 am »

Ok, I built an rgb amp and hooked it to my sg1000, but the picture keeps rolling. Then I hooked just composite video to my tv and the picture still roles.

Is the sg1000 broken or do i need an LM1881??? :blink:

Vertigo · « **Reply #7 on:** October 21, 2003, 09:31:16 pm »

Well seeing as your TV initally accepts the picture, although in black and white, it's obvious that your TV can accept a 60Hz picture but not NTSC colour. So taking that into account, your rolling picture now must mean that you're not getting a 50 or 60Hz refresh rate out of the thing, otherwise you'd have a clear picture, in either colour or b&w respectively. So there's your problem. Check your sync connections.

trol · « **Reply #8 on:** October 26, 2003, 05:52:09 am »

Without the rgb amp it gives color :rolleyes:
I connected the sync wire to composite inside the sg1000 and the rolling became less, the picture is just moving around now.
Is there any way to convert the sync to the right refresh rate? Or maybe I can convert the ntsc rf to pal rf?