Abstract: A Loran-C communications technique and system are disclosed involving appropriate encoding of communication messages and logical multiplication and inversion of encoded signals prior to phase modulation of the Loran-C pulses, with novel bit-flip connections for producing complementary plus and minus modulation position shifts in the first and third and second and fourth, etc., of the Loran-C pulse groups, and with perfect balance irrespective of the nature of the raw data and irrespective of skywave interference.

Abstract: A method of and apparatus for measuring time of arrival of remote Loran-C and related signals and effective time of transmission of local signals at Loran transmitter sites through use of a simulated Loran signal locally generated and coupled into the receiving antenna system that receives the remote signals in a time slot not occupied by the local transmitted signal.

Abstract: This disclosure is concerned with a technique and apparatus for reducing CW and other inband interference in a broad bandwidth RF pulse navigation system to inobtrusive noise through the use of pulse-position random modulation, including, where desired, superimposed random phase modulation, with signal-random modulation code cross-correlation in reception.

Abstract: This disclosure is concerned with generating in a plurality of successive modules, simultaneously and repetitively, a plurality of similar, simultaneous, narrow high voltage pulses, and adding them together in a way that the failure of mis-timing of any module will not prevent the continued operation of the resultant pulse generation. The result is attained by appropriate interconnection of the modules, each of which embodies triggered charging and preferably magnetic pulse-compression and step-up operations.

Abstract: This disclosure is directed to SCR charging or other energy-switching circuits provided with priming and carrier sweep-out networks and the like that normally incur energy losses in the priming and sweep-out processes, wherein such losses are obviated by transferring energy resulting from such processes back to the power supplies.

Abstract: The disclosure is concerned with enabling modular power converter systems, including RF generators or transmitters involving such conversion, employing switching components such as SCRs in the power conversion, to fail in a soft manner as a result of transient electrical or other disturbances so as to permit continued system operation, through the use of individual module d.c. power supplies and circuit design that insures inverter module high output impedance even under SCR failure conditions and that mitigates against SCR failures caused by changes in load phase angle.

Abstract: This disclosure relates to the generation of RF pulses, generally in groups of pulses, through the use of a plurality of sequentially discharged power supplies, the successive discharge bursts of which are fed to a plurality of successive cycle-producing pulse generators, also sequentially triggered to generate a predetermined number of cycles of RF pulse for each such burst.