Step 2: Getting it ready for experiments
In order to work with this circuit, we need to replace all of the useful internal wiring with wires that we can use. To start with, I've replaced the "Lock" switch with a simple wire jumper - although you could just switch it to "unlocked" and leave it there. If you choose to replace the switch, you have to desolder the three connections of the switch - a hit on each joint with the vacuum pump cleaned things up nicely enough that the switch fell out. I just put in a little wire loop and resoldered onto the two "unlocked" pads.