Cheap handheld : Using a real headphone jack

Edit: There is a bit too much humming, i'll use a shielded wire.
I dont care about the video out, but i do want a headphone jack

Let's have a look at the existing headphone jack:

  1. It is not a 3.5mm standard jack
  2. It is converted by the supplied cable to RCA A/V (composite + mono sound)

A quick check showed that the audio is expecting high impedance input and is not able to drive a headphone. Additionally there is a 2.5v DC bias.
No problem, let's use the tiny loudspeaker pins instead, it will give a bit too much power, but that should nt be a problem

Let's remove the original female jack. The pinout is as follows :



The end result looks like that :


The new female jack header is super glued to double sided tape, so in theory it can be removed and is strong against push/pull moves.
You'll have to file a bit the case , because the jack is bigger.
(ignore the RED/BLUE wires, it's just for testing)

And it works fine !
Next the LCD.

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