[Milsurplus] Inverter Adjustment

[Richard Brunner]

I've been playing with the 800-1-D rotary inverter, which is 24 vdc to 120 
vac 800 cycle. In the excitation circuit there is a carbon pile adjustment, 
and a series resistor .  I've had good luck getting good voltage regulation 
adjusting the carbon pile at light load, (key up) and the resistor at full 
load. (key down)   However, there are two ends to the carbon pile, and only 
one end is adjustable and locked.  The other end appears to be adjustable 
but not lockable.  When I screw that end in tight, the voltage goes sky-high 
(140 volts) so that must not be right.  Any experience here?

Richard Brunner, AA1P