This weekend, I finally got a chance to assemble and test a prototype PC Board for the AntDecoder. The board and the software worked fine. The only issue is that I need to add output buffers to the Arduino lines that drive the two BCD ports for the Antenna Switch. The switch uses 12-volt logic and the Arduino is a 5-volt board with 5-volt logic. It is not possible to interface an Arduino output to logic levels above 5-volts.

Here is the initial prototype board that is being used for software development.

AntDecode Proto PCB-1

The interface between the Arduino and the Antenna Switch needs to be open-collector (or open-drain), to support conversion to higher-voltage logic. This will also be compatible with the outputs of the Elecraft K3 Band Data, which uses open-drain outputs. The switch I am using has pull-up resistors to 12-volts DC on the BCD input lines.

Here is a prototype of an interface with switching transistors and open-collector outputs

AntDec Driving 2X6 Port

Not pretty, but it works. So the final step will be to either add the transistor switches to the outputs on this PC Board, or create a second PC Board that includes the switches. I will also be looking for a commercially-available converter board. There might be something that is used to convert TTL circuitry to drive relays. The addition of the output switches should take a couple weekends. I hope to have something finished in the mid-Feb 2018 time frame.