Hi,
Some time in the dim past, I bought a Mirage/KLM APS-1 Antenna Polarity Switcher from a local ham who bought a nice 1990 vintage satellite station but never got on the air. They were designed to switch the antenna circularity of KLM satellite antennas, plus provides a regulated DC output, 5-13 volts. Should work fine the an M2. The front has two push buttons labeled 144 and 432 and a power switch/voltage knob. The back has two phono jacks for the circularity, and two terminal jacks for the adjustable power. It uses a wall wart with a standard 2.1 mm jack. The input power is 11-15 volts DC @ 500 ma.
It is over 20 years old, but truly looks new, with no scratches or dents. The original parts list and instruction sheet are also included. The original wall wart is NOT included, but there is a compatible one included if desired. Pictures and a copy of the instruction sheet available on request. This works perfectly, but is more of a vintage gear item.
$25 firm, including shipping, North America. Please contact me off list.
Alan WA4SCA