Simple demonstration of simple magnetic generator with leds and capacitor

[sooze69]

Okay - most of what is on this blog is gobble-de-gook to me as I have no knowledge of electronics - other than I grew up hearing the words resistors, transistors, capacitors etc as my dad was a TV engineer back in the days when TV's had big glass valves. 

Anyway - I am starting from scratch and trying to make myself a magnetic generator to light up 2 LED's.  I have found some guidance on making a simple one - but I'd like to introduce some other electronic components to expand the concept further.  I'd like to find a way of storing any additional electricity produced to keep the leds flashing (or lit up) for other 20 seconds.  Or alternatively - to stop the LED's from flashing until the magnetics stop moving - kind of like deferring the generated power.  I am hoping someone may have some ideas so I can build my improved generator.  It was going to work by shaking the magnet - and the coil has 1000 turns and the magnet is really really strong! 

Something simple like this would be a great starters project for youngsters to do with an adult without being overly complex.

Suzie

[amspire]

You could charge a capacitor from the generator.

If the generator had a maximum of 12V output, then if you charged a 5,000uF 15vW electrolytic capacitor, it could power a led flashing circuit for 20 seconds  at a current of 10mA per LED and flashing for 0.1 second  every second.

[IanB]

Shaking a magnet backwards and forwards through a coil will produce alternating current that changes direction when the magnet changes direction. So I'm guessing  the simple circuit contains two LEDs wired in parallel back to back so that each LED lights alternately.

Storing the generated electricity in a capacitor is therefore going to require separate rectification to DC. (Thinks: I wonder if there's a circuit topology that can use the LEDs for rectification and can then light the same LEDs from the stored energy?)

On the subject of engaging youngsters, have you seen these?