RGB HDMI Video

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Overview

This article will cover some options you may find interesting when searching for the best quality video for Uzebox. This article is particularly focuses on using SCART(European) interfaces on NTSC(North America among others) televisions. Some points will also be made, later, about using the RGB directly without the use of adapters.


Basics

The basic concept that will be covered is using active converters that take SCART as input and output HDMI in either 720p or 1080i. The advantage is that is it possible to get significantly better video quality out of the Uzebox hardware, even nearing Uzem quality. This is because the analog signal is not mixed down into a composite signal which needs to be separated along with sync. This way there are no signal artifacts causing the blurring and other visual distortions composite suffers from.

The devices themselves can range from very high end machines like the FrameMeister @ $250USD, down to $35USD for capable devices. Like most things, you get what you pay for but to help you out there is a brief review of some of the cheaper models-the only ones I have. They actually do quite a nice job, and for the price, there is really no reason not to have one for Uzebox and all your other retro consoles that have cheap SCART cables available(the majority).


SCART

SCART originated in France and was widely adopted across Europe in all sorts of consumer video products. The standard itself has been used to transfer RGB, composite, CVBS, S-Video, besides other non-standard things. SCART can even have bi-directional communication to turn a television off or such, but that is a large topic left to the interested reader. Cheap adapters allow you to convert different connectors to the SCART standard, since SCART in itself can be a container for many types of video.

For our purposes S-Video and Composite are interesting if you have a standard Uzebox kit. S-Video is by far preferred, and though not as razor sharp as RGB, has a very good picture quality. Some might barely notice the difference. Composite in some situations is poorly scaled by modern televisions, so there might also be an advantage to scale it instead with a dedicated device using a composite/s-video->SCART plug which cost approximately $3USD.

EUzebox owners might already have a SCART interface on their television, in which case this section might not be too interesting. Since RGB is an analog format it must be converted to digital on newer televisions. There could be some possibility a purpose built device can outperform that built into a television. Perhaps even it does not support Uzebox video signal but the adapter does and allows you to use your Uzebox. Another interesting point here is that US, Canada, and other NTSC countries that never had SCART available, can use an EUzebox just fine. It also opens up the door to playing a plethora of PAL consoles on your NTSC television. Many NTSC region consoles will put out RGB automatically when a SCART is inserted.


Equipment

First you need a television with HDMI input. Most adapters tested do no come with a SCART cable, so will need one of those as well if you have EUzebox. It is important to make sure it states it is an RGB SCART, else there is a chance it is the ultra cheap ones that only have a few wires to pass composite and audio. EUzebox does not send out anything but RGB so there will be no picture in that case. These can be commonly found on ebay or such for reasonable prices.

If you have a standard Uzebox console(not EUzebox) then there is no SCART connector on the machine and in fact you may get away without having a SCART cable at all. Instead of wiring your own, wou are best off purchasing an s-video cable and a cheap S-Video->SCART plug. This changes the DIN style connector on the Uzebox over to the SCART connector, and the s-video passes through the appropriate SCART wires unaltered. Then the upscaler takes it to HDMI and you enjoy near RGB quality video, far better than what you remember from the 1980s and 90s in the NTSC regions!

Later on if, like the author, you decide to get SCART cables for all your systems(SNES,Genesis,Saturn,ZX Spectrum,many many support it as well), you might not want to buy separate converters for each one. Instead you can purchase a SCART switch/splitter. Be careful and do your research and the very cheap ones can be poor quality or no pass RGB at all. This will allow you to connect multiple machines to the same SCART->HDMI converter to display one at a time.

It is possible to modify a standard Uzebox to work on SCART TV's without having to use an AD725 to get colour video output.


Known working s-video to HDMI adapters

The following devices have been tested by members of the Uzebox community and are known to work with the standard Uzebox:

Shenzhen Topwin Technology Co. E633A RCA / S-video to HDMI converter cable: S-video and audio input work well at both 720p and 1080p

Topwin-E633A .jpg