Abstract: The present invention proposes a multiple-push oscillator for providing a high-frequency signal. The multiple-push oscillator combines N (at least 3) fundamental oscillators. Through the design of circuit connection, the N fundamental oscillators will operate at odd modes with phase differences of 360/N degrees between their output currents to obtain an output signal of frequency at least three times as large as that of the fundamentals. Therefore, a high-frequency signal source can be more easily designed by the present invention. Moreover, the present invention has the characteristics of high transistor gain and high resonator Q factor.

Abstract: A golf ranging system is provided where a golfer positions a ranging unit at a ball position, indicates which hole is being played and the ranging unit reports the distance to the pin for that hole and/or the distance from the tee for that hole. The ranging signal is a direct sequence spread-spectrum signal and the ranging is repeated many times and an average taken, to improve the accuracy of the distance measurement. Optionally, the ranging system could operate over multiple frequencies to avoid interference. The multiple frequencies are scanned until an interference-free channel is found, or measurements are made at several frequencies and averaged. The pin unit might be housed just beyond the pin and include an offset to the pin. The offset can be set by simply sending an offset signal from a standard ranging unit, or a specially configured course management unit, held at the pin or manually entered via a serial port.