Step 2: The schematic
Use of the small pushbutton:
Sometimes, the circuit doesn't seem to start up immediately after connecting the power supply to it. When you push this button, it'll start working.
However, I never seem to have this problem any more now.
Notice that the uper right and upper left connection are the same. We only have to make this connection once.
You can also see in the other pictures that the PWM driver only has 3 connections. +, - and output signal.
The cross in the middle of the schematic is NOT a connection.