I have been asked about the progress of the AntDecoder project. I have been working with a prototype PC board along with a 2X6 Antenna switch. The antenna switch is a homebrew model made by Mike, K4GMH. Mike was kind enough to provide the switch at minimal cost and also has supported this effort with input to my debugging efforts.
I have written some test software for the Arduino board, that allows me to select one-of-six antennas for each of my two radios. Using a logic analyzer, I can see that this is working, but the switch relays are not being controlled by the AntDecoder prototype.
One small Problem with Logic Levels
The plan was to make the AntDecoder compatible with any switch that could be used with an Elecraft K3 transceiver. It turns out that the K3 uses Open-Drain outputs that can be connected to any supply voltage up to 14 VDC, using pull-up resistors. The switch I have uses a 12-volt supply. I suspect this is common of other commercial switches, but have not yet investigated them.
I will be adding logic level conversion to the setup. I may try something with the Arduino software, to see if it is possible to use it without adding logic-level switching components. But for now, That looks like the most likely outcome.