Finally I was able to test my recalbox in my CRT TV.
I had to use an old SD card with a Recalbox (version 4) that I wasn’t unable to update. With the new recalbox version I wasn’t unable to enter noobs and configure it. I set my Recalbox configuration to NTSC mode (my TV is PAL but it also works in NTSC), I followed the exact instructions from the forum.
It works but I had a few issues to solve:
-The audio had a very disgusting noise, I solved it configuring the audio output in “jack” mode.
-The screen was cropped and I mainly solved it activating the overscan option. I had a better screen but I still have some cropped borders. I don’t know how to adjust the screen to fit my TV.
-The image quality is not as good as the quality of my old PS2 console using the same type of connector, I tested the console to check the image quality and to compare it with the Recalbox. I think the problem is the cable I used with my Recalbox, it’s a cheap Chinese cable and I think is not very good. I’m going to make a new cable with good quality conectors and cable, I expect to get better image quality with this DIY cable.
I think the overall image quality is good, but I expect to improve it with a good cable as I said before ( @tifsmo I don't know why you get terrible image quality).
All I have to say is that you can use the Recalbox with an old CRT TV in order to get the retro style we had back in the 80’s and 90’s.
I think that a good improvement for the Recalbox system will be the possibility to select the image output (Jack or HDMI) in order to avoid the config.txt configuration. If you can select the audio output, why not the image???. I have Openelec with Kodi in another raspberry and you can select the image output.
Thanks to everybody for their support.