Hello,

What is the purpose of the set of holes beside the audio jack?   I assume they serve the same function as the audio jack but I want to make sure.

These holes are for headphones. Ground, Left and Right. Typically a 32 ohm impedance headphone can be driven from this connector. The 3 pin header is the same as that used for the headphone connector next to the header.

The right most pin in the header is the tip of the headphone connector. The middle hole is the ground pin.

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73,
Ron / W4MMP

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