We’re officially starting the 50 days tomorrow, but I started layout out parts and ended up jumping in. This is obviously not how you’d make a light blink on it’s own, but I just stated messing around with a few parts that I happened to have in front of me.
The few microamps that flows through the LDR & base circuit allows a few milliamps to flow through the collector circuit. The downside of this rudimentary approach is that the current through the base never goes all the way to zero, and some newer, more efficient LEDs won’t actually go dark.
Ways we might be able to resolve this – And I’m just riffing
- Use a FET instead of a transistor. If we drive the voltage down below the drop of the LED, it will cut off.
- use a second transistor to amplify the current swing into the base of the first one.
I’m not going to solve this tonight (or possibly ever). The point of these exercises is just to keep doing something every day for like 30 – 60 minutes.
