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General Category => Technical support - Hardware related => Topic started by: betpet on 23:34, 08 July 20

Title: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 23:34, 08 July 20
I picked up an Amstrad CPC 6128 last week and, to my great surprise, it works! The problem is that when I hook it up to a screen, it displays in black and white. Does anyone have any ideas what the problem may be?
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Sid_ on 08:01, 09 July 20
I have got the same symptoms with a cpc plugged on a tv with a scart connector.
12v was missing in the scart. 
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Bryce on 08:15, 09 July 20
Your TV SCART input thinks a composite signal is connected. You'll need to either manually set the TV SCART to RGB or add a voltage source to tell the TV to use RGB.

Bryce.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 10:07, 09 July 20
Thanks for your help guys!


@Sid_ (https://www.cpcwiki.eu/forum/index.php?action=profile;u=2614) and @Bryce (https://www.cpcwiki.eu/forum/index.php?action=profile;u=225) I have this connector: [size=78%]https://coolnovelties.co.uk/coolnovelties/amstrad-video-cables/258-amstrad-cpc-464-6128-active-rgb-scart-cable.html (https://coolnovelties.co.uk/coolnovelties/amstrad-video-cables/258-amstrad-cpc-464-6128-active-rgb-scart-cable.html)[/size]


Are you saying I need to plug the 12v in instead of the 5v to the power cable?  I don't want to try unless you're sure because I don't want to fry the machine.  I plugged the 5v in and it made no difference.







Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Sid_ on 10:17, 09 July 20
NOooooooo  ;D ,
You need to add the 12v in the scart. I don't remember the pins you need to plug, @Brice might know.
It's just a 12v battery you add to the scart.
Like this cable : http://retrocables.es/tienda/index.php?id_product=667&controller=product&id_lang=4

Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 10:33, 09 July 20
Are you saying my current cable is no good?  :o  I don't see a power source for the scart bit.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Sid_ on 10:35, 09 July 20
well I don't say that, but you need to solder 2 pins to add the 12V.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Bryce on 10:36, 09 July 20
Stop! No! That cable is made for 5V to activate the RGB. Don't put 12V anywhere near it. My guess is that your TV either doesn't support RGB or it has to be switched manually. Can you tell me the exact model of the TV?

Bryce.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 10:52, 09 July 20
This is all the info on the TV. I've been looking at various cables and they all pretty much match up to the one I have.


The manual is here:


https://www.argos-support.co.uk/instruction-manual/7923049-toshiba-49-inch-49v6763db-smart-4k-uhd-tv-with-hdr.pdf (https://www.argos-support.co.uk/instruction-manual/7923049-toshiba-49-inch-49v6763db-smart-4k-uhd-tv-with-hdr.pdf)
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Bryce on 11:20, 09 July 20
?? According to that manual, the TV doesn't have a SCART input? Where are you connecting the CPC to?

Bryce.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 11:33, 09 July 20
I'm using a scart converter to HDMI.  One of these:


https://www.amazon.co.uk/gp/product/B07TS1D55H (https://smile.amazon.co.uk/gp/product/B07TS1D55H)


Sorry, I probably should have mentioned that :(
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Bryce on 11:42, 09 July 20
That converter doesn't take RGB, only cvbs (composite), so it won't ever give you a colour picture via SCART from the CPC.

Bryce.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 11:49, 09 July 20
 :picard:


Typical.  Any suggestions?


Would this work?


https://www.amazon.co.uk/SCART-BENFEI-Composite-Adapter-Supports/dp/B085M9Z5D4/ (https://www.amazon.co.uk/SCART-BENFEI-Composite-Adapter-Supports/dp/B085M9Z5D4/)
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Bryce on 12:03, 09 July 20
Well it claims it would.

Bryce.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 12:09, 09 July 20
Thanks for your help.  It's much appreciated. I'll update the thread when it arrives and I've tried it out. :)
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: SkulleateR on 20:54, 09 July 20
Quote from: betpet on 12:09, 09 July 20
Thanks for your help.  It's much appreciated. I'll update the thread when it arrives and I've tried it out. :)
Please do so, I´ve looked for such device but never got around to buy one ...  ;D
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Shaun M. Neary on 21:16, 09 July 20
Quote from: SkulleateR on 20:54, 09 July 20
Please do so, I´ve looked for such device but never got around to buy one ...  ;D

I use this, it works almost perfectly!
https://amzn.to/3iPJeRJ (https://amzn.to/3iPJeRJ)
The picture does display a little to the right off centre, but I think that's only on the Amstrads that do that, I didn't notice it on my Sega Megadrive.

Pro Tip: Power these things from the 5v USB port in your TV, that way the thing powers down when you shut the TV down instead of staying on and burning out.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 22:54, 11 July 20
I got the same result.  How annoying!  There must be something I've missed.  Everything is plugged in as I'd expect it to be.  Anyone have any ideas?  I'd rather not have to fork out for a third converter (As Shaun recommends) unless I know I have to.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Shaun M. Neary on 16:40, 12 July 20
Quote from: betpet on 22:54, 11 July 20
I got the same result.  How annoying!  There must be something I've missed.  Everything is plugged in as I'd expect it to be.  Anyone have any ideas?  I'd rather not have to fork out for a third converter (As Shaun recommends) unless I know I have to.
I regret to inform those things are complete rubbish for Amstrads. Hang on to them for other devices such as Megadrives, etc.

Go with the converter I suggested, it was suggested to me when I was in the EXACT same situation you were in 2 years ago and it hasn't let me down.
Do open it up and get a heatsink put on the chip though, they can burn out easily, and also power it from the TV that way it powers down when the TV does.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 16:42, 12 July 20
Ordered and I will. I'll keep the thread updated when I check it out.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 13:19, 13 July 20
She's aliiiiiive!


It worked.  Shaun's recommended device did the job.  It's a little blurry but that's not a disaster right now. The pic looks more blurry with my shaky hand but it works.  Thanks for your help guys!


It would be great to know what the difference is between that device and the two previous ones I used. It'll be something that people can look for if/when they hit the same issue and there may not be that exact device available.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Shaun M. Neary on 13:26, 13 July 20
That's the cable! The converter displays it a lot brighter than it should do. You can add a resister to bring the levels down and sharpen the picture, or you can order one from retrocomputershack.

If you want to go the first route, have a word with some of the guys here, they know exactly where to place the resistor inside the cable. I wasn't risking it (my soldering skills are a disaster!) so I bought another cable, and kept the older one for a different TV that had a built in SCART. :)

Remember not to keep that converter powered on all the time. The components inside are cheap shit and can die out in no time.
Enjoy CPC gaming in colour! :)
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 13:36, 13 July 20
Fantastic!  So, for the record (I may go through with it), where can we find details on the resistor and soldering it to the cable?
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Bryce on 13:36, 13 July 20
The difference between the converter is that the good one converts RGB into HDMI, whereas the cheap ones only convert composite video to HDMI. Unfortunately the sellers frequently lie and claim that their device converts RGB when it doesn't, making buying recommendations complicated.

Bryce.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 14:09, 13 July 20
*sigh* I guess you don't really know until you've tried it yourself. At least he have a model we know works now. :)
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Shaun M. Neary on 15:21, 13 July 20
Quote from: betpet on 13:36, 13 July 20
Fantastic!  So, for the record (I may go through with it), where can we find details on the resistor and soldering it to the cable?


Paging Doktor @Bryce (https://www.cpcwiki.eu/forum/index.php?action=profile;u=225), can you answer this one please?
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Bryce on 17:45, 13 July 20
The CPC shouldn't need any resistors, maybe there are settings in the device that can be adjusted?

Bryce.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: betpet on 14:04, 14 July 20
Quote from: Bryce on 17:45, 13 July 20
The CPC shouldn't need any resistors, maybe there are settings in the device that can be adjusted?


I think Shaun meant the scart had a resistor soldered to it to tone down the brightness.  I may be misunderstanding here.
Title: Re: Amstrad CPC 6128 in black and white (well, grey really)
Post by: Bryce on 14:24, 14 July 20
Yes, that's what he meant, but as I said, the CPC levels are correct, it shouldn't need toning down.

Bryce.
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