Let's Make Robots!

Stepstick A4988 issue

Recently I came across the following odd observation with a Allergo A4988 based stepstick stepper motor driver. I hope others will redo my experiment and tell if they see the same.

Those who doesn't know the stepstick can have a look here: https://www.pololu.com/product/1182 Of course mine are cheap clones I got from ebay, but they should work the same.

Regulated Joule thief, how?

Many of you have seen or read about a Joule thief, and for the rest of you: http://en.wikipedia.org/wiki/Joule_thief. They come in a great varieties, google easily finds them. One thing that I like about the Joule thief is that it is so forgiving about the applied transformer, the circuit simply adapts to that ever you throw after it. No need for calculations or anything.