This Servo Tester can be used with or without an external receiver NiCd battery pack. From the tester, the three wire cable goes to your servo or ESC. If your speed control has a BEC circuit, you do not need a separate 4 cell receiver battery. If your ESC does not have a BEC circuit, or if your are testing servos, you will need a receiver battery. Connect the receiver battery to the two-wire radio connector.
The Model 105 Servo Tester has two operating modes.
1. The manual-control knob adjusts the servo signal from one millisecond (low throttle) to two milliseconds (high- throttle).
2. The push button switch disables the control knob and causes the servo tester to automatically put out a square wave which alternates between one millisecond and two milliseconds. This mode is used to test servos and will cause the servos to alternate from one side to the other side at about two times per second.