Heavily catching up, just listened yesterday.

Loved it. It was entertaining to listen to you doing every single step and seeing you do it before my minds eye. I'd never thought about describing it in such detail, but you have a point there. Surely there are a lot of listeners just starting out with this stuff and you pick them up right at the beginning, to lead them further on.

The 3V3 are sorted out by Mike, so let me comment on the "speaker". It's worth noting that whenever you say speaker, you actually mean "buzzer". The buzzer includes already some electronics to generate the tone, so we hear the beep. With a speaker (or headphone,...) on its own, you only will hear crackling sounds the moment you close or break the circuit. Due to the low resistance of the speaker coil, there can be a high current flowing, which might damage it. So when using a speaker, please add a series resistor or capacitor. 

Regards,
Michael
