There are probably several versions of the front panel knob.

When we started shipping the product, the knob's mechanical design was tricky and needed careful adjustment.

Oh, but when that knob was aligned, it was magical. It felt like a million bucks in your hand. It spun like a top and magically coasted to a stop like something from the control panel of a spaceship. But it needed tight tolerance for the magnets to have the right feel.

During the years that we manufactured the generator, we kept trying different designs and manufacturing techniques for the knob in hopes of making the mechanical design simpler, cheaper, and easier. I left the team by that time, but I know from talking with them that they were still trying to reduce manufacturing cost and the need for alignment. It does seem likely that some later versions of the product had knob internals that differed from the original design.

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