Abstract: A detent hold and release mechanism on a manually positioned valve controller which electrically signals a servo controlled conventional hydraulic control valve. The mechanism has a detented operating position and a spring-returned neutral position when the detent is released; the detent is held in operating position by a locking pawl urged by a permanent magnet. The mechanism is released by energizing an electro-magnet positioned adjacent the permanent magnet with reverse polarity whereby the combined magnet forces are neutralized, thereby releasing the pawl and allowing the valve controller to return to the neutral position.