exxos's Atari, Amiga & retro forum

Trying to work out the best way of getting a decent video signal from my 800xl. So far I've tried:

1. RF output - this has vertical lines on the background and a kind of 'zigzag' pattern along the left and right hand edges where the blue screen meets the black border.

2. Composite out via the din connector - Similar to RF but with less noticeable vertical lines and slightly sharper

I'm considering the s-video mods that are all over the internet to help improve things. My one concern with that is I don't really have any s-video TVs or monitors, so I'll still need some additional converter beyond it, even if the picture quality improves.

The other option is one of the RGB boards I've read about, but finding a supplier in the UK seems rather difficult.

Ultimately, I'm wondering if I'm just being too fussy and expect too much from my little 8 bit machine and should live with the slightly poor display?

What do people think? How far should I go?

If your serious , RGB.. I did it to my 2600, its well nice! https://www.exxosforum.co.uk/forum/viewt ... 110#p25746

That's interesting - was that a UK supplier?

I've been looking at the UAV board and appear to have found someone supplying them in the UK:

https://shop.ctrl-alt-rees.com/products ... 7800-8-bit

Anybody had experience of ordering from them as I'm not familiar with them?

You might want to have a look at Sophia. Have a look here: https://thebrewingacademy.com/

Bit expensive I know, but definitely looks nice.

There is also VBXL from Lotharek: https://www.lotharek.pl/productdetail.php?id=54

Again, not the cheapest, but a nice solution for RGB.

Thanks @rubber_jonnie yeah I did look at those too. They just seem a bit over the top for what I'm looking for I think. Also adding complexity is the shipping costs involved - especially from the US.

Think I'm either going to do the DIY mods for svideo and see how things look from there, or see what is available under 50 quid from UK based suppliers?

PeteW wrote: ↑Sat Sep 19, 2020 10:23 am Thanks @rubber_jonnie yeah I did look at those too. They just seem a bit over the top for what I'm looking for I think. Also adding complexity is the shipping costs involved - especially from the US.

Think I'm either going to do the DIY mods for svideo and see how things look from there, or see what is available under 50 quid from UK based suppliers?

I did do a mod for S-VIDEO out on my 65XE, and I'm sure there was a similar one for the 800XL. Unfortunately the link is dead, so I need to see if I can find the doc I downloaded. It only cost about £10 for all the parts.

Thanks @rubber_jonnie . So far all I've done is feed a cleaner 5v supply to C51 and remove L5. Made a tiny difference, but not much

I'll do a recap anyway, but wondered if noisy old electrolytics could be making things worse?

If you can find the mods you've had success with, that would be really useful

Hi all

So I've done some of the simpler svideo mods and undoubtedly have a sharper picture, however I still had zigzag interference on the blue background of the screen.

I played around and have finally (I think) found the solution:
Using an svideo cable, if I touch an earth wire to the metal outer of the cable plug where it goes into the monitor port of the computer, the interference basically vanishes.

So, my idea is to ground the actual monitor port where it solders to the MB. This will ensure that the cable and the shielding in the cable is grounded in the same way.

I'm not quite sure why this works to be honest. I tried using the ground on pin 2 of the connector in the cable but that was no good, it had to come straight from the ground plane of the motherboard.

Anyone know why the monitor port isn't grounded as standard? I assume I won't hurt anything by permanently grounding it to the MB?

PeteW wrote: ↑Sat Sep 19, 2020 10:41 am Thanks @rubber_jonnie . So far all I've done is feed a cleaner 5v supply to C51 and remove L5. Made a tiny difference, but not much

I'll do a recap anyway, but wondered if noisy old electrolytics could be making things worse?

If you can find the mods you've had success with, that would be really useful

Sorry, but I can't find the link to the mod I used anymore, it seems like it's gone for good. I've got a VBXL on order at the moment, so I'll do a write up when I install it.