Vertex VXA700 plumbing to PS PMA4000.

Not a trivial job to get Vertex PTT to be controlled by PMA4000.
We removed the PTT switch which happens to actually be two switches.
We are replicating this function with a DPDT relay. The PTT pin of PMA4000 will ground coil and do the same thing as your thumb pushing onto two individual switches at the same time.
Y10-07-17