I.l.s. air-borne receiver

Abstract

Abstract 1,118,979. Radio navigation. CSF-COMPAGNIE GENERALE DE TELEGRAPHIE SANS FIL. 3 Oct., 1966 [4 Oct., 1965], No. 44150/66. Heading H4D. In an I.L.S. receiver utilizing, e.g. in the localizer section a main A and a reserve B low-frequency channel each affording D.C. signals representing the sum and the difference of the 90 c/s and 150 c/s depths of modulation, a comparator circuit output 12, the sum signal from channel B and an automatic gain-control signal from the high-frequency stages of the receiver feed a NAND circuit 13 giving a " 0 " output if the inputs are present simultaneously and a " 1 " output if one or more inputs are missing, the NAND circuit output and a further output from circuit 12 pass to a NOR circuit 14 such that an output issues therefrom if there is no signal input at all, and the latter output, if present, conditions a switch 11 between the sum signal output of channel A and a flag warning device on I.L.S. indicator 18. A switch S permits testing of the alarm system.

Inventors

• 👤 Edouard Mouradian

Bibliographic Details