Help: Raspberry Pi with a Portable TV as a screen?

Question

Hey Ben,

I'm trying to find a way to add composite video to an old OPTIMUS portable LCD TV for a Raspberry Pi project, but information is scarce.

Then I found out you used to use them on old portable game console hacks.

Here are some pictures of what I'm working with, do you think it's possible?

Rov

shabaz · Answer

Hi Rovert, Check out the data sheet (PDF) for the Mitsubishi M51348FP IC on that board, you can see there is a ceramic resonator (probably the one above the two cans in your second photo) and you could try to feed the signal into there (temporarily break a track or lift that resonator out and extend it on very short wires and use a capacitor (e.g. 10nF) in series with your output from the RPI) - try both ends, one should work, and ground is the center of that part. Bear in mind you need to enable the composite output on the RPI (it defaults to HDMI) - or use some other composite signal source for now. EDIT: Now I look a bit closer, it appears this could have been the areas where additional stuff is needed for the model with A/V input - see the photo below, the red circled area is possibly where the video wire was connected, and the pink area is some level adjustment perhaps, but is missing in the BoM for this model. Possibly SW200 (the white area on the left with the red marker paint on it) was used to control it. In the absence of a circuit diagram it would be hard to know for sure. Anyway, the ceramic resonator method mentioned above hopefully could work - it won't harm anything to try.

Help: Raspberry Pi with a Portable TV as a screen?

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