A Precision Electronic Goniometer 1965/00/00. This material was shipped to Fenwick Library Special Collections, George Mason University, Fairfax, VA on 23 October 2000. A description of the navigational system for airplane landings under Instrument Flight Rules (IFR), invented by John Warfield, for which he holds a patent. The system was built and marketed by Wilcox Electric Company of Kansas City, Missouri in 1965, initially for use at small airports where a 10 watt VHF Omnirange System is sufficient. The voractor-based electronic unit, without moving parts, was intended to replace the older mechanical units which were hard to adjust, and whose precision tended to deteriorate over time, due to mechanical wear. The offprint is three pages of printed text and three pages of figures (drawings & photos) Fig. 1 Block Diagram of the Electronic Goniometer Fig. 2 Schematic of a Capacitance Bridge Modulator Fig. 1 Schematic of Varactor Diode Bridge Modulator Fig. 4 Photograph of Assembled Varactor Diode Bridge Modulators. Fig. 5 Photograph of Swept Response of a Varactor Diode Bridge. Each Individual Trace Corresponds to Maximum Output Power From One Pair of Bridge Arms. Center Marker, 113 me, Sideband Markers ±5 mc. Fig. 6 Schematic of the Function Generator Used to Produce the Varactor Diode Modulating Voltage Fig. 7 Photograph of the Function Generator Waveforms Used to Drive One Bridge. Guy Gooch, the co-author, was a fellow employee at Wilcox Electric who was also John's graduate student at Univ of Kansas, working on his doctorate r.w. circa 2001 NOTE THIS WAS A CONFERENCE PAPER DESCRIBING THE PATENT, NOT THE PATENT PAPERS WHICH WERE TITLED "DOUBLE BRIDGE NETWORK FOR PRODUCING SIGNALS…….. … THE CONFERENCE PAPER WAS SENT TO GMU, I THINK, BUT I CAN FIND NO RECORD OF IT IN THE FINDING AID. MAYBE IT WAS PLACED IN THE SAME FOLDER AS THE DOUBLE BRIDGE NETWORK PATENT FOLDER. I CAN'T TELL FROM LONG DISTANCE. .r.w. 25 August 2013