Model 35×2 Rebound Chronograph

The Oehler Model 35×2 chronograph is specifically intended for use in rebound testing of athletic balls (golf, tennis, baseball, or other) or similar projectiles. The chronograph, attached to two Oehler Model 57 Photoelectric Screens, measures both the inbound velocity as the ball travels toward a rebound surface and the outbound velocity as the ball rebounds back through the same two screens. Both inbound and rebound velocities are recorded and summarized. The unit is powered from 120 volt ac converted to 9 volt dc by a wall mounted transformer power supply. The paper tape printer uses standard 2.25″ adding machine paper with a replaceable ink roller.


The Model 57 Screens function with all projectiles larger than .17 caliber and faster than 300 fps. Infrared diodes are used for the light source. They have the same outside dimensions as the older Model 55 screens. More detectors allow better coverage of the shooting window. The output pulse is +12 volts of approximately 2 milliseconds duration. More…