Stedy's RGB to SCART cable

[dJOS]

Originally Posted by orange

@Kitch, dJOS

why don't you put capacitors in SCART socket, it has more room?
I also have ghosting problem. and some noise.
but most of noise goes away after connecting shielding.

I'm not using scart, I'm connecting into a gbs-8220 because my Samsung monitor only supports 15khz at 60hz and not 50hz.

[Stedy]

@Djos,

Have you tried changing the +5V power supply for the GBS8220?

If there is excessive ripple on it, it could couple into the PCB power rails and cause unwanted disturbance.

Nice soldering, getting the capacitors inside the DB23 housing.

I'm going to update the diagram on the web to add those capacitors as an option.

@Kitch

Trying to get a fully shielded cable is not easy on the Amiga, certainly not to meet current EMC requirements. An overall shield/braid will help a little bit but you may need individually screened RGB wires for best picture.

That said, my prototype cable only had an overall screen, could not expect much for a £1 SCART cable.

[dJOS]

Originally Posted by Stedy

@Djos,

Have you tried changing the +5V power supply for the GBS8220?

If there is excessive ripple on it, it could couple into the PCB power rails and cause unwanted disturbance.

Nice soldering, getting the capacitors inside the DB23 housing.

I'm going to update the diagram on the web to add those capacitors as an option.

No I havent as I dont have any suitable spare 5v PSU's lyng around - I did try adding a ferrite core to the power cable at the GBS-8220 end but that didnt make any difference to the slight ghosting effect seen around the mouse pointer.

Cheers, I was quite happy that I managed to cram them in.

[orange]

I've just tried the alternative sync from composite out. picture looks much better, centered, nothing missing on left side. only problem, A4000 lacks CVBS I've found a solution to delay sync, but its rather complex: http://www.sega-16.com/forum/showthr...uit-and-layout

I have an Amiga 1200 which I have connected to an old CRT TV using an Amiga RGB Scart cable i bought off ebay. The cable looks good quality and the PQ is quite good, but the black level is elevated, so blacks are grey and everything is a little washed out. I checked via a straight composite connection and that has the same issue. I'm guessing its some sort of voltage issue, can It be corrected and if so how?

Many thanks.

[spajdr]

Try to ask a guy with nick Oge on amibay, he doing his own RGB cables for various computers and they are best on market

[demolition]

Originally Posted by Lvader

I have an Amiga 1200 which I have connected to an old CRT TV using an Amiga RGB Scart cable i bought off ebay. The cable looks good quality and the PQ is quite good, but the black level is elevated, so blacks are grey and everything is a little washed out. I checked via a straight composite connection and that has the same issue. I'm guessing its some sort of voltage issue, can It be corrected and if so how?

How about turning down the brightness on the remote? Most TVs have independent settings for each input.

Originally Posted by demolition

How about turning down the brightness on the remote? Most TVs have independent settings for each input.

I have 3 consoles and the Amiga connected to the TV via a scart switcher, only the Amiga needs adjusting. My TV is an old CRT and it disables the controls when connected through the AV (scart). So my only real option is a fix in the Amiga or scart cable.

[orange]

perhaps its that DC offset, try StT.

Do any of the cables currently available to buy have this dc offset? I'm not very handy with a soldering iron.

[Amigan123]

Thanks for the schematic.

I had a basic Amiga to Scart cable that suffered from a shimmering/wobbly effect on my Samsung LCD.

I added the 330 Ohm resistor to the composite video and it fixed the problem and the image is now rock steady.

[Anders1984]

I guess this cable also goes under the superior cables in the first post?

http://amigakit.leamancomputing.com/...oducts_id=1087

[Retrofan]

I love amigakit's rgb-scart cable (have a couple). Great image quality.... but I've never used the audio connectors cables it has; I just use the amiga ones to connect to the hi-fi.

Will I get something better using them instead?

[demolition]

Originally Posted by Retrofan

I love amigakit's rgb-scart cable (have a couple). Great image quality.... but I've never used the audio connectors cables it has; I just use the amiga ones to connect to the hi-fi.

Will I get something better using them instead?

No, it will just send the audio to the TV. Since I have my TV hooked up to the stereo, I use the connectors and feed the audio through the TV to the stereo. Then I won't have to use a seperate cable for audio.

[Retrofan]

So, sorry my poor knowledges: Coudn't it be improved adding "betterpaula" to the cable?

[demolition]

Originally Posted by Retrofan

So, sorry my poor knowledges: Coudn't it be improved adding "betterpaula" to the cable?

I think that just mixes left and right to get rid of the 100% stereo separation so it will sound better, particularly in headphones.

[FOL]

Originally Posted by demolition

I think that just mixes left and right to get rid of the 100% stereo separation so it will sound better, particularly in headphones.

Indeed, I used to feel dizzy and sick when listening to Mods with headphones, lol.

[Stedy]

@Anders1984

Amigakit make cables to my design, they are the best on the market. Adding the resistor to the CSYNC signal from the Amiga is the most important fix for modern TVs.

@Retrofan/FOL/Demolition

When I built and tested my Audio mixer, I sampled the outputs and uploaded the MP3s here:

http://www.ianstedman.co.uk/Amiga/de...mixer_mk2.html

Normal, cross faded and better Paula circuit was tested, listen for yourself. I prefer the cross-faded audio on headphones.

I am re-evaluating that project no I've seen what my Chinese PCB supplier can do.

Ian

[demolition]

Originally Posted by Stedy

When I built and tested my Audio mixer, I sampled the outputs and uploaded the MP3s here:

http://www.ianstedman.co.uk/Amiga/de...mixer_mk2.html

Normal, cross faded and better Paula circuit was tested, listen for yourself. I prefer the cross-faded audio on headphones.

Ok, I see now that the BetterPaula circuit is not for cross-fading. I prefer the cross-faded version on headphones as well. The BetterPaula version sound horrible tbh.
Also, the cross-faded BetterPaula version doesn't sound like it has been cross-faded.

[Retrofan]

With BetterPaula the volume increases a lot. I like the BetterPaula Cross Fading. I'm not using headphones though.