Trouble with a false RGB TV

[abaudrand]

Hi,

I recently used a SONY TRINITRON KV-14M1B TV and I had no troubles using my atari 7800 with it despite the picture is not very colorful.

I've just purchased an old Amstrad 6128+ with RGB output and each time I plug it the picture is fine for about 2 seconds then it become bright grayish. I mean the black still black but all other graphics become bright.

I've spent some time finding manuals on internet but not exactly the same model. On the manuals they use a symbol for the RGB input that look like this:

 

  
   _________
-> /  . . .  /
 /_________/

On my model , it look like this

 

 

I couldn't find a chart of symbol but is it a RGB input with a strange Gamma curb?

Anyone heard about this?

Edited June 6, 2011 by abaudrand

[GroovyBee]

That's a SCART socket in the bottom picture. Are you using a Peritel system or an S-Video modded system?

[abaudrand]

I'm using a SCART cable for the 7800 and for the Amstrad. Normally these ones output RVB signal compatible with some CRT display.

I've changed the TV to another brand and I don't have any issue but the display is blurry compare to a trinitron tube. this becoming annoying if you want to program on an amstrad, not for playing game.

 

[GroovyBee]

For the 7800 what is on the other end of the cable? Is it S-video modded or a Peritel 7800?

[abaudrand]

Original Peritel 7800 cable but the 7800 isn't the issue at all, I guess its the Sony trinitron which doesn't have a normal RGB input.

[roland p]

From my memories, maybe it has to do something with pin 16. The signal on this pin will let the tv select between composite and rgb:

http://en.wikipedia.org/wiki/SCART

 

Does your scart cable has this pin connected?

Edited June 6, 2011 by roland p

[abaudrand]

From my memories, maybe it has to do something with pin 16. The signal on this pin will let the tv select between composite and rgb:

http://en.wikipedia.org/wiki/SCART

 

Does your scart cable has this pin connected?

 

Thanks Roland, thats a good idea to check if the Amstrad deliver the right tension here. I'll ask my bro to bring his voltmeter friday to check the Pin 16. I've also found a way to enter into service mode but I also need a sony remote to do so.

Here is the link I've found that might interest other people who have a sony TV set:

http://myweb.accessus.net/~090/sonypal.html

(link for NTSC also available)

[abaudrand]

Ok We checked the output in Pin 16 and there is no signal at all. Thanks Roland P.

So I we're gonna try to add a 1.5V battery to the wire and hope it will make the TV switch.