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The control board is based around a Microchip PIC16F1939 micro controller. The user interface is via a Barton Blue LCD and a rotary encoder to change frequency and select menu options such as CTCSS tone. The 16F1939 will program the ADF4002 on the synthesizer board via the SPI bus and store last frequency in memory IC1 AT9356 along with CTCSS state. The CTCSS is programmed via a 6bit parallel bus. U1 LP2951 is a 100mA LDO regulator which will provide the 5V supply for IC1 and U1.

The prototype PCB is four layers top and bottom carry the signals and the inner layers are used as power and ground planes.

Version 2 added some resistors in series with the rotary encoder inputs and the PTT input to protect the PIC.

PCB Update 05/08/16

Added 1k resistors is series with rotatory encoder inputs to protect the PIC and rotary encoder denounce logic while using programmer/debugger.

Hand placed, built PCB