John Bail

US Patent:

40018245, Jan 4, 1977

Filed:

Apr 28, 1975

Appl. No.:

5/571843

Inventors:

John W. Bail - Fort Washington PA
Ronald Lee Powell - King of Prussia PA
Frank Patterson Smith - Dresher PA

Assignee:

Narco Scientific Industries, Inc. - Fort Washington PA

International Classification:

G01S 956

US Classification:

343 73

Abstract:

A ranging timer allows decoded data pulses to toggle a flip flop, thereby initiating a transmission cycle. In a specific embodiment, the data pulses condition a second flip flop to energize the DME transceiver. During the next negative excursion of a 96 microsecond reference clock, the second flip flop is toggled, and during the next period of the reference clock, the decoder is disabled, the transmitter-modulator is energized, the ranging timer is enabled, and the first flip flop is reset. Since the time between the decoded data pulses is variable, jitter is built into the commencement of each transmission cycle.