Lighthouse kit - how it works

Kits
1

I recently ordered the lighthouse soldering kit. https://www.sparkfun.com/products/14635 Is it possible to get a 2-paragraph “what makes it work” that I could explain to kids? Is there a name for the arrangement of the transistor circuit (like push-pull, or are any of the resistor/capacitors a tank circuit). Also, there was in the description “by changing the value of the resistors you can change the flashing pattern”. Which resistor values should I modify should I change the flashing? Thanks!

2

What level are the kids?

3

Google “astable multivibrator” and a ton of information should come up. You will probably need to distill down what you find so that kids can understand it though. [This instructable might be a good starting point for kids, it’s the same type of circuit used on the lighthouse kit.](https://www.instructables.com/DIY-an-Astable-Multivibrator-and-Explain-How-It-Wo/)

4

https://youtu.be/adz6WqnWqJw?t=305

Here is a really good visual explanation but might be more for 8th-12th (American School System) grades.

5

The kids are boy scouts, so 11~18ish. Thanks for the resources - these are awesome!

6

A popular way of explaining electricity to younger (even some college classes) has been using water as a metaphor. The transistors are like valves and capacitors are like buckets. You can have all kinds of fun explaining it. The Feynman technique is the perfect way of learning something and explaining it to others: https://mattyford.com/blog/2014/1/23/th … ique-model. I wish you the best of luck and have fun!

7

So the Astable multivibrator example in the video has 2 LEDs. The lighthouse circuit https://cdn.sparkfun.com/r/600-600/asse … useKit.jpg shows the LED with a 220 Ohm resistor on the LED, and the other side has an 82K Ohm. The 220K/10uF combos are the tank circuits, so I should assume that the light on/off time is matched, correct? 50% duty cycle? If I replace the 82 K Ohm with another LED and a 220 Ohm resistor, it would be the same circuit in the video, right? If I increased one f the 220K ohm resistors, it will change the on-time or off-time depending upon whether I changed R2 or R3. Right?

8

KansasBot - The Feynman technique looks really interesting. Funny you should mention the water metaphor - I have always liked it. In fact, my presentation pretty much revolves around it… I have attached it in case you have any interest…

Thanks again!

ElectronicsMB_Presentation.pdf (1.69 MB)

9

Sorry - several updates to the slides, if anyone is following…

ElectronicsMB_Presentation.pdf (1.69 MB)