Clockwise movement indicates that the frequency is too high on the incoming system. Counter clockwise movement indicates that the frequency is too low. A steady light dot at 6 o’clock position indicates zero frequency deviation and 180 degrees phase deviation. Exact synchronization. frequency and phase accordance is achieved when the light dot is steady at the 12 o’clock position (when the green LEDs ignite).

The M8100 scale is made up from 38 bright red LEDs. The resolution provided by the 38 LEDs is almost as fine as a pointer synchroscope, however the LED based design is far better at withstanding environmental influence from vibration, temperature and humidity.