I considered doing that but as far as I know nobody makes a battery holder that has the same footprint as the 2032 battery with tabs. The board has three plated through hole locations for the battery, the battery holders only need two in a straight line. That means modifying a double sided board that has the entire area under the battery on the component side as a solid copper plane connected to the (-) side of the battery. The (+) side is fed through to to a trace on the bottom of the board. Certainly could be done but to me would be too unreliable because there is no pad to hold one end in place. It's easy enough to desolder and replace the battery as long as the conformal coating is removed where it needs to be. But just that fact means that the butt set is not as weather resistant as it once was, really the conformal coating should be touched up (which I didn't). A battery holder makes that impossible and is a point of failure.

-Hal

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