Abstract: A scan alignment system and method for calibrating a scan path for a directional antenna system is presented. The scan alignment system calibrates the scan path by generating a scan path, scanning the directional antenna through the scan path, receiving a signal signature responsive to the scanning, comparing the signal signature with a reference signature, and determining a corrective calibration to apply to the scan path that minimizes the difference between the signal signature and the reference signature. In an embodiment, the reference signature is modeled based on the directional antenna and the intended scan path.

Abstract: A SECAM decoder for deriving the signals for a color display from the composite color picture signal determined largely by digital means having digital line switching, multiple delay lines, decoder center frequency clamps and indicator of drift of encoded white, dual digital phase detector for each phased locked loop decoder, switchable de-emphasis and a waveform squaring circuit whereby ease of adjustment to different recording subcarrier frequencies or to sequence color and memory standards is provided.

Abstract: A system for limiting an FM signal to produce outputs which are TTL compatible, yet retain the zero crossings of the incoming FM signal as long as the amplitude of that signal remains above a chosen minimum and the frequency remains less than a chosen amount.