Wire it up: A Relay Oscillator

I’ve wired up Experiment 8 from the book Make:  Electronics by Charles Platt.  I’m 90% I’ve got it right.

By adding a 100uF capacitor to experiment 7, the relay stays in the non-relaxed switch position for a little under a second, then very briefly relaxes, and then re-engages.  This is why the green LED (relaxed state) blinks on every second, but the amber LED appears to be almost solid.  The amber LED actually is blinking for a split second, but it’s imperceptible in this video.

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