CPC 464 SCART Cable doubts & Restoration CPC Keys [Pag. 4]

[G40rocket]

Hello,

I have a CPC 464 with no CRT monitor so i was searching some tutorial in this forum and another places at internet for build my own SCART cable at home.

I have all the pieces avaliable and some soldering experience so it will be no problem at all.

Unfortunately i have no 100% sure about what is the correct scart configuration, some people add resistors at the cables and i'm really confused.

I guess that, this is the right scart configuration right ?




If all is good i have two important questions:

1) the connector views (6 pin DIN + SCart) is from the back where the wires will be welded, right ? ( i don't want burn or damage the CPC inside with wrong schematics)

2) Where i can plug the 3.5mm audio cable ? Is not supposed the SCART cable provides sound (like image) with no audio extra cable ?


By the way, another question is for the PSU, i will buy a universal 5V with 3A (for more safety) for power the CPC. What is the right polarity for CPC 464 ? Center is negative or positive ?

Thank you in advanced. 

[McKlain]

The audio jack goes here:


http://upload.wikimedia.org/wikipedia/commons/f/f8/Amstrad_CPC646-IMG_7196.jpg


This may be located on the back or on the left side of the computer. It's an stereo sound output. You won't hear the loading sounds through that connector, just the audio from the sound chip.

1) the connector views (6 pin DIN + SCart) is from the back where the wires will be welded, right ? ( i don't want burn or damage the CPC inside with wrong schematics)

That's what it says on the image.     By the way, I don't think that you can damage the 464 by soldering the video cables in the wrong positions.


The resistors and other stuff that people use on their scart cables depend on the tv you are using with the 464. Sometimes all that is not needed. I built my cable so long ago that I can't remember when I did it, and it has nothing more than wires.

[Munchausen]

I recommend using the "alternative RGB wiring" with a capacitor, from the wiki (and Bryce). None of the other wiring schemes worked for me.

[G40rocket]

McKlain and Munchausen, thank you very much for your time and answers.

I will built the Scart cable from the schematics and if will not work with my TV (Samsung LCD 24") i will change to the method that Munchausen wrote.

I will give you news about this.

[Bryce]

If you are going to build your own, then you may as well order all the parts at the same time and build this version: TV SCART cable - CPCWiki

It's almost identical to the version you posted above, but the capacitor will make it more compatible with modern TVs.

Bryce.

[G40rocket]

Hey Bryce, thanks for the tip.

I saw that schematic too but i need to add a capacitor or a resistance ?

What is the voltage for the capacitor ?

Capacitor = ??

[Bryce]

No resistor, just a capacitor: Electrolytic 100µf 10V (exactly like the one in the picture you've included), remember that the polarity is very important! This capacitor is enough to trigger the RGB selector in the TV and give a stable signal on a modern LCD / Plasma TV.

Bryce.

[G40rocket]

Thank you again Bryce.

Will tell some news in the next weeks.

[a7mag3ddon]

Sorry to jump on thread but i also need advice on RGB cable.

This is what i get when using a premade purchased scart lead on my HDMI box....



And if i go direct into the TV i get the following screen (the blue/black banding is moving like a loading screen)



Im Desperate to get this sorted, any ideas?

[Bryce]

How long is the cable? Is it properly shielded?

Bryce.

[a7mag3ddon]

Yeah it is sheiled, I just opened it up and it looks quality built inside.

[a7mag3ddon]

Just checked my eBay purchases, 2 Mtr is the length.

[Bryce]

It might just be the TV that's not happy with the signal. Have you tried the cable on other TVs?

Bryce.

[a7mag3ddon]

No i only have the 1 TV, the socket on the back does say AV1 (RGB) on it though. it cost me £3,000 i hope it does work in RGB mode.

Is it worth taking the cap off and replacing with something else? going through the converter box, text is crystal clear apart from the light blue ghosting.

Here is the back of the TV..

[Bryce]

The TV is working fine in RGB, your problem is that there's noise on the signal. What PSU are you using? If it's a cheap Chinese Switch-mode PSU then I'd advise trying a different one.

Bryce.

[a7mag3ddon]

PSU on the 6128? I'm using MP2

[Bryce]

Hmmm, then the noise isn't coming from there either. Maybe the TV just doesn't like 15khz signals. It happens.

Bryce.

[a7mag3ddon]

But what about the blue ghosting which isn't direct to the TV?

[a7mag3ddon]

can the blue signal not be tweaked to somehow be in line with the rest of the text?

I contacted supplier of cable for advice and he said hes never seen the blue striped effect on a TV before, hes going to send me a cable that has an active line (my psu plugs into it) to try.

[Bryce]

It IS in line with the rest, just there seems to be another signal mixed with or interfering with the blue signal.

Bryce.

[a7mag3ddon]

Its weird. I would have said faulty 6128 but its the same on my 464 as well.

Is it worth trying a different type of converter?  Im currently using a HDV-8S model, there are others available that do it.

[a7mag3ddon]

Perhaps this will work better? Specs look OK.

http://www.maplin.co.uk/p/nikkai-scart-to-hdmi-convertor-1080p-n32jq

[VincentGR]

This works fine for me, I have better picture than every vga/hdmi converter I've seen.
Made by Anemos of flashback-computing.
http://flashback-computing.com/viewtopic.php?f=38&t=200

[a7mag3ddon]

I think this is the diagram of the new cable supplier is sending, but why is it 12volts?

[VincentGR]

I think this is the diagram of the new cable supplier is sending, but why is it 12volts?

It gives the ready signal on many TVs. Many of them doesn't have picture without it or flickering, sometimes blink every 2-3 secs.
I powered it via cpcs external psu (from an external hd psu) and now from my multi-psu for all my micros (a std pc one)