Abstract: A modular neon sign control system with a plurality of discrete neon letters, numbers or symbols, each with plugs to plug into at any place along a continuous electrical rail. Each neon letter, etc. is a single tube having its own driving inverter and digital decoder. Dip switches set a unique digital code into the decoder for each letter. A programmed memory controls a system encoder which sends coded signals to each decoder to compare with each letter's unique code. Those letters receiving the matching digital signals are activated or deactivated according to the program. The letters, etc. of the sign can be operated simultaneously, serially, randomly, in a pattern, or in a flashing manner. Power from an ac adapter is supplied along with the signals from the encoder to the electrical rail, and the decoder separates the power from the coded signals. The letters may be individually and easily prearranged and substituted in a sign.

Abstract: A lightweight hand-held scanning device for repetitively scanning a laser light source having a laser light generating means and at least one high speed scanning motor controlled by a resonant motor circuit which automatically controls the frequency and amplitude of oscillation of a high speed scanning motor. The frequency and amplitude control is accomplished by using a single feedback signal obtained from the windings of the motor which indicates resonance and which also measures the amplitude of oscillation. The feedback signal obtained is a second harmonic of the driving current. The circuit can be utilized to tune and maintain the motor in a resonant oscillating mode. By controlling both the frequency and amplitude of oscillation the high speed scanning motor can maintain a consistent scanning speed and use less power.