Fessenden v. Radio Corp. of America

22 F. Supp. 777, 1938 U.S. Dist. LEXIS 2279
CourtDistrict Court, D. Delaware
DecidedMarch 24, 1938
DocketNo. 1054
StatusPublished
Cited by1 cases

This text of 22 F. Supp. 777 (Fessenden v. Radio Corp. of America) is published on Counsel Stack Legal Research, covering District Court, D. Delaware primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Fessenden v. Radio Corp. of America, 22 F. Supp. 777, 1938 U.S. Dist. LEXIS 2279 (D. Del. 1938).

Opinion

NIELDS, District Judge.

This is a- suit by Helen May Fessenden, as administratrix of the estate of Reginald A. Fessenden, charging Radio Corporation of America with infringement of two patents: No. 1,617,240 granted to Reginald A. Fessenden February 8, 1927, on application filed January 28, 1922, for “Method of Wireless Directive Signaling” (hereinafter called the first patent); and No. 1,617,242 granted to Reginald A. Fessenden February 8, 1927, on application filed October 13, 1924, for “Wireless Transmission and Reception” (hereinafter called the second patent). The defenses are invalidity and noninfringement.

Fesseiiden was a pioneer in wireless. He contributed to the scientific as well as the commercial development of radio. He is the accredited inventor of the “heterodyne” receiving circuit.

Radio started in 1864 with the theoretical work of the English mathematician James Clark Maxwell. He demonstrated that light travels through space in the form of extremely short electromagnetic waves and that there are other electromagnetic waves that travel through space at the same speed but are longer and therefore invisible. In 1888 Heinrich Hertz proved the correctness of Maxwell’s theory by demonstrating that these invisible electromagnetic waves exist and that they follow the ordinary laws of light waves. Hertz generated electromagnetic waves from 1 to 10 metres in length. He used small apparatus. The smaller the apparatus, the shorter the wave length. Marconi transferred Hertz’ work from the laboratory to the practical field. He increased the distance these waves could be transifnitted by connecting one side of the spark gap to a metal plate buried in the earth, and the other side to • a wire extending vertically to a considerable height. Hertz connected a small horizontal antenna with his spark gap and transmitted short horizontally polarized waves a few feet. Marconi’s structure produced long and vertically polarized waves. By 1898 Marconi transmitted electromagnetic waves 14% miles; by 1901, 200 miles; towards the end of 1901, he spanned the Atlantic ocean. In 1899 Marconi announced that the distance to which signals could be sent varied with the square of the length of the vertical antenna. Investigation by others corroborated the correctness of Marconi’s conclusions. In keeping with this teaching defendant erected at its Tuckerton Station an antenna tower 835 feet high operating 'on a wave, length of about 16,000 metres.

Wave lengths below 200 metres were assigned to amateurs. Occasionally they received some transatlantic signals but the signals were regarded as freaks. Between January, 1922, and November, 1926, the radio art adopted wave lengths between 14 metres and 214 metres for long distance commercial communication. The use of waves of these lengths for long distance communication was well known to the art and numerous descriptions thereof were published. For example, Radio Broadcast of July, 1925, contained an article by Marconi. Here he said: “It was reserved for the years 1923 and 1924 to show conclusively that such short waves could, and did, perform efficiently and reliably most of the things which the experts had considered until then either impossible or impracticable. * * * The cycle of radio investigation sweeps back to something-very similar to that of the first radio experiments.”

Original Application for First Patent.

January 28, 1922, Fessenden filed his original application for a patent entitled “Wireless Direction Finding”:

“My invention relates to finding direction by wireless, by means of the so-called Fessenden Pelorus, and has for its object greater efficiency in finding direction by this method, and more particularly the elimination of errors, and greater reliability of indications'.
“ * * * applicant has found that still other sources of inaccuracy remained, and that the readings still occasionally failed to give the true direction. Applicant has now traced the causes of these errors, to the presence' of wire guys, smokestacks, [779]*779deckhouses and the like; and possibly other causes, for the sources of error seem almost to be inexhaustable, and some are variable, due to salt water on masts, etc.
“But whatever the cause, applicant has experimentally discovered that all of this latter type of error source is substantially eliminated if the wave length of the directive signals is shortened down far below what is now, or has been heretofore, used, i. e. if, instead of using a wave length of 10,000 metres or of even 1,000 metres, or even 300 metres, which last is now considered a very short wave length, the wave length is shortened down to the order of 5 (five) metres. If this is done the results obtained seem very reliable, especially if two wave lengths are used, say 5 metres and 8 metres; or 4 metres and 7 metres; both wave lengths being of the order of magnitude of 5 metres, or even less.
“Applicant is not aware of the reasons why these wave lengths give so much more reliable results. Possibly, or even probably, it is partly due to the fact that wave lengths of thisa order of magnitude are not affected by neighboring conductors, as stays, etc. unless in close proximity; and even when in proximity the fact of disturbance is indicated by the different ratio of intensities on the two wave lengths. Also it may be that the neighboring conductors, as guys, etc. are of a longer natural period than the order of magnitude of 5 metres and so are not absorbed or bent' to any great extent. Whatever the reason, experiment shows that the results obtained are so reliable that all difficulties of this method of direction finding appear, at present, to be overcome.”

Hogan, a witness for defendant, sums up the disclosure of this application: “What Fessenden teaches in that application as it was filed is that he thought or proposed that by using wave lengths of the order of magnitude of 5 metres length, one could avoid the errors in bearing or direction finding that had before that date been encountered when longer waves were used for wireless direction finding.”

Direction finding was a well-known use of radio signaling before 1922. It involves the determination of the line between a given receiver and a given transmitter, for example, between the radio compass aboard ship and beacons in the harbor. Bearings of nearby stations are sufficient for triangulation whereby you can locate the ship and the channel of the harbor in a fog. The disclosure of the application was addressed to a real problem. Any method or apparatus that obtained the results then claimed by Fessenden would have been a valuable invention.

This application was directed to the problem of avoiding errors “in determining direction by wireless.” The sources of error were stated as wire guys, smokestacks, deck houses, etc. Applicant proposed to avoid these errors by utilizing wave lengths of the order of 5 metres, mentioning 4, 5, 7 and 8 metre wave lengths. Applicant stated, “much more reliable results” were secured “due to the fact that wave lengths of this order of magnitude are not affected by neighboring conductors.” The original disclosure of this application was with respect to direction finding and shdrt distance work. Five-metre waves can be used only up to 15 miles in direction finding.

Five radio engineers testified what wave lengths were comprised in the expression “of the order of 5 metres”:

Hansell said he would understand a range of 4 to 6 metres.

Beverage said plus or > minus 20 per cent.

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Related

Fessenden v. Radio Corp. of America
103 F.2d 1012 (Third Circuit, 1939)

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Bluebook (online)
22 F. Supp. 777, 1938 U.S. Dist. LEXIS 2279, Counsel Stack Legal Research, https://law.counselstack.com/opinion/fessenden-v-radio-corp-of-america-ded-1938.