Can I connect my retro console to an HDMI television?

The older consoles were designed to be used in the already outdated and retired tube televisions. The result of connecting them to current TVs? The less horrible. However, more and more CRT TVs are getting more and more degraded and it will reach the point where they will disappear. At this point it is where it becomes interesting to install an HDMI Mod to our console.

We have acquired a retro console in the second-hand market, the kind that was not connected to a television via HDMI, but using analog signals for tube televisions. Luckily our TV has the necessary connections, but when we turn on both devices and see the result, our eyes start to water because of the poor image quality displayed. In any case, this phenomenon is normal, the operation of the old televisions was not the same as the current ones and the consoles of yesteryear were not going to be designed with a type of screen that nobody had at that time.

Can I connect my retro console to an HDMI television

What is an HDMI mod and why are they so valued?

An HDMI Mod is nothing more than a modification to an old console that allows you to install said video output port on it. This is a modification beyond adding a simple communication port, since we are adding a video signal that the video system was not designed for.

We have to start from the fact that many of these systems did not use an image buffer, that is, they did not generate the next frame in the video memory, but rather kept up with the electron beam and, therefore, their generation times image depend on a way of generating video that is no longer used. That is why the resulting image is so bad on many systems. Therefore, an HDMI Mod is not limited to video output, but is a much more complex circuitry than all of this.

Thus, it has been filled with electronic projects in which lovers of these systems, aware that tube televisions will soon finally say goodbye and stop working, have decided to create this type of modification. However, the problem is that each manufacturer used its own way of communicating with the television, meaning that a different solution had to be invented for each system.


Why are HDMI Mods necessary?

An old PAL TV had up to 625 scan lines, an NTSC up to 525 lines. Although in both cases not all were shown. Of course, this was in the progressive mode, where the action happened at 30 frames per second. Instead, to be able to go to 60 FPS it was necessary to shoot the interlaced mode, where the lines dropped to half. Therefore, most systems of yesteryear used resolutions at 240p or worse, in some cases even 224p.

The problem of the number of scan lines

What is the problem? Well, the minimum resolution of the HDMI cable is 480p, so we find that half of the lines are missing and it is necessary to generate them somehow. What’s more, this is one of the main reasons why your old console looks so bad on your LCD or OLED panel, since, to fill in the gaps, many HDTVs duplicate lines in the worst possible way.

Problemas video compuesto monitor

No, games didn’t really look like that

This is not the only problem, but we also have to take into account that pixels do not exist in a tube television, but that each scanning line is continuous and the color changes are made through changes in voltage produced by the video signal. Hence, the graphics of many games are distorted. Unfortunately, the new generations have ended up playing them on emulators and have come to the conclusion that this is how they were designed visually.

In the gallery above you can see examples of various retro consoles from different generations and companies and as you can see this is a widespread problem that not only worsens image quality, but literally destroys the artistic presentation in games.

How does an HDMI mod work?

Once we have defined the problem and you have seen it with your own eyes, we must clarify that the idea is not a modification in the way the original console works, but rather a piece placed between the console and the LCD television or OLED whose job is to ensure that the information of the video signal is correct and thus the information is presented correctly. So if the modified system is very old, it’s going to need to do its job very quickly so that we don’t notice it and there isn’t a single delay.


There are several ways to achieve the purpose, some use Rasbperry Pi and other similar SBCs. On the other hand, there are people who prefer the use of an FPGA for this task. Some output the signal at 480p, the lowest resolution supported by HDMI, while others are more complex and include a scaler. The job of all of them is the same, to provide the correct communication between the new televisions and the old systems.

His only counterpart? They are not easy to install and require knowledge of electronics, which leads to them being extremely expensive to fit and there is a danger of breaking the original console. However, if one day your CRT TV breaks and your old console still works, they are totally worth it.

Is it the same as an RGB mod?

RGB outputs were very popular in the past, but many systems due to age or cost reduction came out without them. RGB mods are designed to continue using conventional tube televisions, but with a higher quality video signal than the one that came from the factory. So we are not talking about transforming an analog signal into a digital one, but about amplifying the RGB signal from the video output to achieve more vibrant and vivid colors. Interestingly, many older systems had the ability to output RGB signals, but this was limited at the last minute due to lack of time or budget. If you are lucky enough to have a still functional CRT television at home, these types of modifications will increase the visual quality of these systems.

Super Mario 64 Mod RGB