I always wanted to have a scrolling text below our TV screen – like the once we see on the news with scrolling text while the TV program is not interrupted. Talk about multitasking deeds yeah? Watching your favorite cartoons while also watching the headlines.
To insert text or any figure into a TV screen without actually interrupting the current show we need to super impose the signal being fed to the video channel. This would also include a stable synchronizer and of course we need to time the whole thing up so that the text we want or the super imposed signal we want will be positioned in the right location and also for it to be recognizable. Bruno Gavand made just that, with a PIC12F683 he tapped into a PAL TV’s video channel inserting text to his TV screen in real time. The circuit is so small that Bruno actually just powered the PIC12F683 on and let the program do its wonders.