I invested few more hours into my Fyoog today!
You need to have a close look from the front to see the change:
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But on the back there is a lever:
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Which can be moved from left to right - surprise surprise:
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And when we switch of the sun....
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I was my first time using LEDs and a soldering gun. Lessons learned: Touching the front of the gun hurts and does not make much sense...
Cheers
das mo