Signal Quality. Spektrum telemetry modules keep tabs on the quality of the signal coming to the receiver and send this information back to the transmitter where it is represented on the LCD screen using a familiar signal bar scale.
A pendulum is a weight suspended from a pivot so that it can swing freely. When a pendulum is displaced sideways from its resting, equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the equilibrium position.
Pendulum saw or swing saw: a saw hung on a swinging arm, for the rough cross cutting of wood in a sawmill and for cutting ice out of a frozen river. Abrasive saw: a circular or reciprocating saw-like tool with an abrasive disc rather than a toothed blade, commonly used for cutting very hard materials.