Transistors!

Way back when, the only way to turn something on and off was with a physical switch, which are prone to failure, until transistors came around!  Transistors are like mini switches that can be turned on by adding a very small charge.
The type of transistor we used was the MOSFET.  To be honest, I had a bit of trouble wiring up the transistor, when I was a kid, we would just stick things together and see how they worked, no fancy transistors, or even resistors... I got it working eventually, and used it to turn on and off a Lego motor.

questions for "Tuesday Feb 12th"

⌘ With the LEGO motor wired as above (powered by a battery and controled by the logo), program the LogoChip to turn the motor on and off. Use an oscilloscope to monitor the LogoChip output pin. Does the LogoChip have any trouble controlling the motor? Feel much torque it takes to stall the motor.
     . It actually works quite well like this, compared to wiring it directly to the logo
Attach another battery pack:  Wow it's really strong now