The Main Control Box contains 4 circuit boards.

Looking at “image A” you will see 3 circuit board mounted on a vertical bracket.
Starting from the left:

Pololu 18v25 Simple Motor Controller purchased from ServoCity. This motor controller provides a Pulse Width Modulated (PWM) signal to the trolling motor and provides infinite speed control and motor direction control.

Pololu Jrk 21v3 USB Motor Controller purchased from Servo City. This motor controller provides a Pulse Width Modulated (PWM) signal to the tilt linear actuator. This controller is used with feedback from the linear actuator for closed-loop speed or position control,

Pololu 6V Step Up/Down Voltage Regulator from ServoCity. This regulator is used to provide a regulated 6VDC from the 12VDC mains. The 6VDC is required for the steering servo motor.

The 4th circuit board in “image A” that is in the lower lefthand corner is ServoCity CAT6 Sending Board (boosted) that can either connect to the Handheld Control Box – Wired Version or the Wireless Receiver Box.