Frequency and Phase Modulation

Frequency and Phase Modulation

    Both frequency and phase modulation of the r-f carrier or audio sub-carrier have received a considerable amount of thought and study. It may be that here lies the secret of successfull long distance transmission of radio facsimile.
     

    The following citations are typical of the published or issued patent art covering this method of transmission.

    Alexanderson (U. S. Patent 1,830,586, E. F. W. Alexanderson).

    Runge & Schroter (U. S. Patent 1,914,898, W. Runge and F.Schroter).).

    Schroter (U. S. Patent 1,937,131, F. Schroter).

    Newa (Journal I.E.E., Japan, Vol. 54, No. 5, p. 433, May, 1934, Y. Newa).

    Osawa (Rep. of Rad. Res. in Japan, Vol. 4, No. 3, pp. 48-49, October, 1934, Z. Osawa).

    Hammond, Jr. (U. S. Patent 1,977,438, J. H. Hammond, Jr.).

    Wright & Smith (U. S. Patent 1,964,375, G. M. Wright and S. B. Smith).

    Aamodt (U. S. Patent 2,094,052, T. Aamodt).

    R. K. Potter (U. S. Patent 1,777,016, R. K. Potter).

  • (C) Marius Rensen

[History] [Historical] [Progress of Wire Facsimile] [Start of Radio Facsimile] [Commercial Point to Point] [Broadcast] [Facsimile Tape] [Comparison of Wire and Radio] [Radio Propagation] [Radio Facsimile Systems] [Time Modulation] [Amplitude Modulation] [Frequency and Phase Modulation] [Scanning Equipment] [Mechanical Scanning] [Recorders] [Synchronizing] [Facsimile Tape] [Machine Design] [Multi Channel] [Color Facsimile] [General] [Conclusion] [Inventors] [Facsimile Makers] [Patents] [Home] [Home]