? Finally found the issue with using the GPIO pins on the Wandboard ARM machine. The GPIO pin I expected to use was muxed for use with a second SD drive. That they identified it in the diagrams for external use was the problem. Using a different external pin and re-designating it in the .conf file did the trick!? The 3.0v output drives an opto-isolator to run the PTT on a Yaesu FT-1800 with some current limiting resistors.
Curiously, I discovered I still have the KAM Plus and Yaesu FT270 I used in the 80's.
