Today I spent about four hours in the lab fixing some stuff for the PA automation. I did solder cables with pull-ups and decoupling capacitors in the control box and also added connectors to those cables. I made sure to label them at once so that there are no mix ups in the future which might cause failures. I also soldered the cables for the 230v supply voltage for the three different switches power supplies and tested them, they seem to work fine. I also added a fuse for the 230v (2A). The stepper motor driver boards got 10v zener diodes to protect the driver MOSFETs. I used regular flyback diodes first but since they “consume” the same amount of current when turning the motors manually the motors had quite a lot of torque making it hard to turn them by hand. So with the 10v zener diodes that problems goes away and I can easily turn them by hand. Since the idea is to make the amp manually tunable and then just save the positions, they need to be easy to turn.
Some blurry pictures