can anyone vouch for this composite/s-video mod?

[8bitwidgets.com]

I am in the process of upgrading my game shrine to have all s-video capable outputs..   this kit is on ebay

 

https://www.ebay.com/itm/284935701272?hash=item42577dc318:g:zGsAAOSw0nJiYKjj&amdata=enc%3AAQAIAAAA8PjD0vB0SWs%2FPRdxB%2BDEiC3zlLo9%2FqMAUTiNA2xWltvGVEWTLKDdAnKhftq5dE7M03QZStuFOr4gV%2BI8cx%2B%2Bql9UkbZoabUCkII9OZ%2Bqzy%2Bevze2vK2CO8SE4b174ow54td10zFfXjgT32KeulrqUMjJ18WaPkWLXSDctzwtyue1i%2BMzsR1cPw5sP11rhWlUiFCB7ySnCqYsfBV6Qt9sEHU8yvaoAMMzYqoPFhXuUcrEjUJHQmrDU9HCBot8EWpmHAQZDE0nXJFG05IKN%2FECdNxoyuQMeLPZFZ%2Fq0%2B7eAyJKaKxW%2FcJCpTqFj0xdhaO7yw%3D%3D|tkp%3ABk9SR9C1trWKYg

 

It looks like it checks all the boxes, but wondered if anyone can vouch for the picture quality.  I have the one sold from Turkey and I'm very happy with the picture, but it's composite only, so looking to upgrade

[+sixersfan105]

He's a well-respected member of the AtariAge community, @the_crayon_king, having been around these parts for seven years, so that's good enough for me! He first posted about his original O2 mod here and then he made some tweaks and discusses those here.

[8bitwidgets.com]

sounds legit!   i'm going to order a couple as i have a few O2s I need to give the treatment.  

[the_crayon_king]

On 6/2/2023 at 3:46 PM, sixersfan105 said:

He's a well-respected member of the AtariAge community, @the_crayon_king, having been around these parts for seven years, so that's good enough for me! He first posted about his original O2 mod here and then he made some tweaks and discusses those here.

Well respected? I'm blushing ;)

 

There is one important caveat with the O2. The clearer you make the picture the more readily you can see the sawtooth pattern around pixels. Last I remember I was able to eliminate this by adjusting settings on the OSSC (particularly sampling phase in 4x mode). I wasn't able to figure out a clean way to fix this in the CPLD side of things. All O2 mods would have this issue unless they do some retiming of the signals; which would probably take a FPGA.

 

Feel free to ignore the below:

My most current theory that I have been going off is that there is some sort of jitter in either the video signals or the clock itself.

Since adjusting the sampling phase of the OSSC fixed this issue that must mean clock to the CPLD needs to be phase shifted. 

I'll need to do research the best way to go about phase shifting a clock. Maybe the CPLD itself can do it?

[8bitwidgets.com]

9 hours ago, the_crayon_king said:

The clearer you make the picture the more readily you can see the sawtooth pattern around pixels.

thanks for the response.  i've been using this one however it's composite only and yours caught my eye as I'm moving up to S-Video with an S-Video compatible Extron 1616.  This mod has given solid results so I'm curious what might be different or maybe it's the s-video area that has issues?

 

You can see in this video me filming my O2 composite modded system:

 

This is the mod I am referring too and you can see it pretty much puts it all out there in terms of what it's made up of:

 

If yours can look at least this good I wouldn't expect any better, but this one hasn't experienced any sawtooth issues unless you're talking about something more subtle? 

 

[the_crayon_king]

15 hours ago, Caleb Garner said:

If yours can look at least this good I wouldn't expect any better, but this one hasn't experienced any sawtooth issues unless you're talking about something more subtle?

It is subtle on S-video and composite (per my memory). It also seems to go away sometimes based on a myriad of conditions perhaps most notably the console warming up.

Those captures are RGB. You will have to zoom way in the see the issue.

 

On lower video outputs like rf, composite and svideo the sawtooth will just look like a fuzzy border around pixel edges. I am not completely certain if S-video wouldn't have some sawtooth pattern too. I believe the same is true for my mod or any other mod., but there are alot of factors that could make a difference as far as TV, video scaler, etc etc.

 

I have seen the same issue on random youtube videos before I had even made this mod. So I think this is something inherit in the console itself. Which could have a bunch of possible fixes as far as adjusting the existing timing circuit. I just think if phase shifting works for the OSSC then shifting the phase of the clock to the video kit should do the same thing? That was my theory anyway.

 

[8bitwidgets.com]

Sounds like the issue you’re referring to is very subtle which is totally fine. I am not super picky. I just want a clean solid picture and good color. RF is so noisy compared to composite that it looks great in comparison.  If s video is no worse, I will be perfectly happy with a display of this quality as seen in the video. I mean, it really does make you wonder how much better can s video make graphics from 70s era consoles.