These are the circuit diagrams:
This is the layout:
This is the Analog Circuit:
This is the digital rear connections
This is the front controls
This is the processor diagram:
These are the output circuits:
These are the display drivers:
This is the 7-segment display:
This is the Preamble Integrator. It recognizes a pulse put before the serial string to allow time for the serin command. In wireless applications it reduces the interrupts from noise and interference.