Infringement is alleged of letters patent No. 1,958,031 to E. L. Bresson, issued May 8, 1934, for a radio receiving system. The usual issues of invalidity and noninfringement are raised by *965the answer. Claims 3, 5, 6, 7, 9, and 10 are in issue.
The subject matter is one of considerable interest, relating as it'does to a receiving set designed to receive signals from broadcasting stations over both long-wave and short-wave bands.
The drawing and specification disclose an antenna which has connected to it a plurality of inductances, illustrated at 10' and 101 of the diagramatic drawing. The energy picked up by signal is transferred selectively from these inductances in parallel paths through oscillating circuits. These circuits are adapted to amplify and to rectify by means of oscillating circuits connected in cascade with the inductances. The oscillating circuits are so designed that the inductance 10' will respond to a band of carrier long-wave frequencies of standard broadcasting signals; and the inductance 101 to transfer selectively the energy of the band of so-called shortwave frequencies. Following the radio frequency stages of the circuits there are the usual stages of audio frequency. These are so connected as to be common to the two paths of amplification so that a single translating device, as a loudspeaker, may be employed. There is also provided a switch for connecting the translator and the source of power to either the short-wave amplifying and detecting means or to the long-wave amplifying and detecting means, and for disconnecting the translator and source from one or the other of said means.
Claim 10 of the patent may be regarded as typical. It reads: “In a device for receiving long or short radio waves, the combination comprising an antenna, shortwave amplifying and detecting means, long-wave amplifying and detecting means, a source of power, a translator and a switch for connecting said translator and said source to said first-mentioned means and for disconnecting said translator and said source from said last-mentioned means and vice versa.”
It may be observed that means for receiving long or short radio waves through the medium of an antenna and providing for amplification and detection with a source of power and loud speaker was old in the radio art. If then there is any novelty, it must be that which results from the particular combination set forth.
Some question arose at the trial as to the meaning of the terms “long” or “short” radio waves as used in the specification. The defendant urges that the terms are relative and that they cannot be defined without a standard of comparison. On the other hand, the plaintiff contends that “long wave” and “short wave” have accepted connotations in the art; that long waves embrace a band from 200 to 550 meters and short waves a band of 15 to 50 meters.
I think it only fair to conclude that Bresson, in his specification, was sufficiently clear, for he refers only to “long wave range of present day broadcasting stations and also throughout the range of the relatively short wave lengths of existing short wave broadcasting stations.” To endeavor to give a different meaning to these terms as employed in the claims would not .be justified.
Other terms in the claims require no particular interpretation, since they are all well understood in the art, though it may be observed that the switch referred to in the claims is not described or limited except by reference to its function.
The disclosure of the Bresson patent is of two separate parallel paths of tuning and of radio frequency amplifying and detecting of the signals received, followed by a common audio amplifying path and translator. With one path not in use, battery energy that would otherwise be used in lighting the idle tubes is conserved.
On July 25, 1911, the Navy Department in a communication relating to wireless. telegraph installations stated that the bureau desired to establish a standard calling wave length for ships of 600 meters, a standard calling wave length for shore stations of 1,000 meters, and to improve the sharpness of tuning of all wireless transmitting apparatus.
Directions were given for inductively coupled oscillation transformers for ships, and it was said: “In addition to the calling wave-length, as many sharply tuned waves for communicating as the apparatus will permit, with full value of condenser, should be arranged for by providing plug sockets on primary and secondary of oscillation transformers with plugs; connecting leads, or by some other suitable arrangement.”
The directions propose to divide all ships into two general classes, “long-wave ships and short-wave ships.” The latter class would include vessels suited for com*966municating' wave lengths from 300 to SOO meters, and vessels which use the wave lengths above 600 meters would be in the former class, and were to be designated “long-wave ships.”
Shore stations were also directed to be equipped with inductively coupled oscillation transformers. Wireless stations were to be furnished with two receivers, of which one was to be type I—P—76 receiver. Connection for the receivers was shown in the diagram transmitted with the letter of July 25, 1911, received in evidence as Exhibit JJ. These receivers were used with a listening-in key and telephone cords, so that one ear of the operator “may listen on one telephone for calls on one receiver and the other ear on the other telephone for calls on the other receiver, the key providing for connecting both telephones to one receiver.”
One of the receivers was to be adjusted for receiving a 1,000 meter wave from shore stations and the other for receiving a 600 meter wave from ships. A variable condenser was employed with the short-wave receiver. The witness Clark testified that this form of duplex receiver was frequently used by the Navy during that early period.
There was no battery connected with the circuit as illustrated in the sketch, Defendant’s Exhibit JJ. The device known as the I—P—76 receiver, 1912-1913 type, is a two-receiver set, one adapted for short and the other for long wave reception, and a listening-in key with telephone leads. The diagrams and descriptions of this receiving system show the two receivers tuned to different wave bands. Fig. 3 of this instruction book discloses a similarity to the defendant’s receivers, in that the position of the switch arm in reference to the secondary coils gives a different coil value tunable over a different range by the common condenser.
The 1914 Navy use was that of a double-deck receiver. In this type the range of the so-called short-wave receiver was from 500 to over 2,000 meters, and for the long wave from 1,500 to 7,-000 meters. The photograph shows these receivers combined in a single cabinet for use with a common antenna, a common detector, a common telephone translator, and a common power source, a built-in switch by which either wave channel could be selected and used to' the exclusion of the channel not selected. This must be regarded as an important use, for with the subsequent development in the use of vacuum tubes it is difficult to see how invention can be ascribed to Bresson over the structure and circuits here disclosed.
Van Dyck described the installation and use in the Navy of radio receiving equipment during the period from 1917 to 1919. Referring to the drawing RY 43 F 220A, Van Dyck explained that the receiving arrangement consisted of a standard Navy short-wave receiver, a long-wave receiver, positioned side by side, an audion control box containing a radio frequency amplifying tube and detector positioned above one of the receivers, an audio frequency amplifier, and a switch for connecting the four instruments referred to.
The operator could listen for calls on his own station of two wave lengths at the same time. If he desired to listen to a signal of a 500-meter wave length, he could connect the antenna to the shortwave receiver. That would connect the input side of the detector to the output of the receiver circuits, and it would also connect one part of the receiver circuit to another part of the tube circuit —referred to by Van Dyck as a “tickler,” a part of the regenerative .arrangement. Thus he would have a short-wave receiver with regenerative or audio frequency amplifying power.
■The short-wave receiver with its tap coil could be tuned to any desired point within its range of 250 to 3,100 meters, the long-wave from 1,000 to 10,000 meters. The switch employed is described as a four-pole switch, so connected that two of its blades controlled the input connection of the' audion detector, so that the audion detector could be switched to either the long or short wave receiver by means of those two blades.
Another significant use was that of the Radio Corporation of America at River-head in July, 1924. The company had stationed at Riverhead in 1920 three long-wave receivers on a single long aperiodic antenna. For long-distance communications wave lengths from 5,000 to 23,000 meters were used. As early as" 1923 in this experimental station observations were made on short-wave communications. Before July 29, 1924, short-wave receivers at that station had been adapted to receive signals of 70 meters wave length. At that time the control system consisted *967of the separate long-wave receivers tuned to the different wave lengths from which the station was receiving signals from Europe, and the signals were then transferred to New York over tone lines, at which point they were transcribed by the operators. Both the long-wave and the short-wave signals passed through the common control board. The engineer at Riverhead was charged with the responsibility of covering the signals that went through to New York. He effected this communication by plugging a pair of telephones into a jack adjacent to the signal on the switchboard. By “jack” is meant a switching device such as is used in telephone practice. The operator thus could cover all of the switchboard signals.
The practice of monitoring, which meant a jacking of the circuits, was started with their first commercial operation about July, 1921, and was applied to the short-wave receivers as well as the long-wave receivers. By inserting the plug into a jack on the switchboard, the operator could listen selectively to any one of the receiving circuits.
Bresson’s own prior public use is relied on by the defendant as a defense. Plaintiff’s Exhibit 19 is a sketch which Bresson made in 1924, showing a four-tube receiver. Radio frequency amplification and detection of short waves are effected by one tube, and that of long waves by another tube. Audio frequency amplification and translation of the output of either tube were secured by two additional tubes and a terminal loud speaker. A little later in 1924 he made a six-tube set in which the radio frequency amplification and detection of short waves were effected through two tubes and associated tuners in one channel, and long waves similarly by two tubes in an alternative parallel channel. This set included an audio frequency amplification and translation effected by the remaining two tubes and a terminal loud speaker, with a switch connected to one or the other of the amplifying channels selectively. This prior use was not pleaded by the defendant, but was proved by the plaintiff at the trial. It is difficult to see how the plaintiff can avoid the inference that these two receivers, particularly the six-tube set, embodied the essential features of his invention as disclosed in the patent in suit. Bresson testified that before Christmas of 1924 he took both of these sets to Thorn’s house. # There one set was installed and many people came in to observe it. Short-wave broadcasting signals were received on a _ band below 100 meters. He admitted that Thorn’s technical men knew how the receivers were made and how they operated.
Thorn testified that Bresson wanted him to manufacture and sell radio sets such as were shown him in 1924 and 1925. He said that he used the radio that Bresson installed in his house “for a couple of months”; that, besides himself, his wife and children, friends of his saw it in operation, and in particular a Mr. Arnold, of the Onondaga Auto Supply Company. Thorn had invited Arnold in the hope of securing him as a possible distributor. Then, too, employees from Thorn’s shop went to his home to see the operation of the set. Bresson did most of the demonstrating. They were told that by throwing the switch the set would go from one receiving band to another. -As a result of the demonstration and negotiations, Bresson became associated with the Thorn Machine Tool Company on January 1, 1925.
The proof thus discloses a public use of the Bresson invention in 1925, more than -two years prior to his application for the patent in suit. Such public use is a bar to a patent. Egbert v. Lippmann, 104 U.S. 333, 26 L.Ed. 755; Hall v. Macneale, 107 U.S. 90, 2 S.Ct. 73, 27 L.Ed. 367; Mayer v. A. & H. G. Mutschler et al. (C.C.A.) 248 F. 911; Covert v. Covert (C.C.) 106 F. 183; Wende v, Horine (C.C.A.) 225 F. 501.
Invalidity is also asserted because of prior patents and publications not cited in the proceedings in the Patent Office.
The catalogue of the De Forest Radio Telephone & Telegraph Company, published December, 1919¿ shows a circuit consisting of an antenna, coil, primary condenser, telephones, crystal detector, and the necessary connections. The set is tuned to different wave lengths by turning the knob of the variable condenser. Such operation changed the value of the tuning condenser and enabled the operator to adjust to any one of a continuous series of wave lengths in a band having a definite upper and lower limit. The limits were fixed by the size of the coil and the capacity of the condenser, as the capacity was varied. If the operator wanted to listen to a wave length outside the *968band but covered by the range of the condenser, he could do so by changing the size of the coil. The coils were physically changed. This De Forest catalogue reference is of value in showing the state of the -art.
Cabot patent No. 858,569, granted July 2, 1907, relates to space telegraph systems and to receiving systems. The object of the invention was to provide a plurality of oscillation detectors; each one of a plurality of signal indicating devices to be associated with a different oscillation detector. Two resonant receiving circuits are attuned to different frequencies and their interposed resonant weeding-out circuits are each attuned to the same frequency as its corresponding resonant receiving circuit. The patentee states that, when it is desired to receive waves of lower frequency or of longer wave length, certain switches are opened; when it is desired to receive oscillations of still lower frequency or still greater wave length, other switches may be thrown. The patent provides for two separately coupled paths connected to a common antenna and to a common translating device with plug-in switching means.
Of this patent Mr. Hogan said that the act of transferring the telephones from one detector to the other changes the receiver from a short wave to a long wave and permits the operator to listen to either without hearing the other.
Though Cabot does not refer to the broadcasting of long waves and short waves, referred to in the patent in suit as long-wave and short-wave lengths of present-day broadcasting stations, the same principle is nevertheless involved.
Though the Cabot patent, cannot be regarded as an anticipation, for the radio broadcasting art had not been developed at that time to a degree which would disclose an anticipation, it is of importance as bearing on the question of invention.
The next patent referred to in the defendant’s book of prior art is that to Ide, No. 1,394,555, granted October 25, 1921. This invention relates to an electrical transformer. Nine sets of three coils are provided in a holder, each set with switching contacts. By turning the holders, it is possible to switch into circuit any one of the twenty-seven coils. The Ide receiver and the defendant’s receivers have in common vacuum tubes, radio frequency amplification, and tube detectors; the band change is accomplished by switching the arrangement of coils, and the same tubes and same tuning condensers are used for all the wave bands. A common antenna is employed and likewise a translating device. In Ide there is a single tube, but its filament remains lighted whenever the set is in use. Thus fundamentally there are no electrical differences between the arrangement of Ide and that of the defendant.
In British patent to Lea, No. 238,338, granted August 20, 1925, on an application filed June 26, 1924, provision of means for the reception of a number of wave lengths by associating a number of tuning systems with a common amplifier or detecting arrangement is shown. Each tuning system may be adjusted to a desired wave length, and any one of the systems may be coupled to the amplifier by means of a switch or relay. The inventors state: “By using such an arrangement it is possible to leave the receiving apparatus tuned permanently to the several wave lengths,” etc. Claim 1 of that patent reads: “Wireless receiving apparatus comprising a number of tuning systems each adapted to be independently adjusted to a desired wavelength, in which any one of such tuning systems may be coupled to the aerial system and to a common amplifying or detecting arrangement by the actuation of a switch.”
The drawing and specification disclose a regenerative vacuum tube, ah amplifying detector with two sets of coils and two tuning condensers, one for each set of coils, and a multiple switch for connecting into the circuit through one of these two sets of coils, and in that manner changing the wave length of the receiver.
“Radio News” for April and May, 1922, describes a receiving set comprising long-wave tuner employing duo-lateral coils, a short-wave regenerative tuner, and a detector and three-stage amplifier. Either the long or the short-wave tuners may be used by throwing a four-pole double-throw switch. Wave lengths from 150 meters to 20,000 meters can he covered. The duo-lateral coils are interchangeable. The four-pole double-throw switch is one which transfers four circuit terminals to either of two positions. The absence of a wiring diagram in this article impairs its value as a reference.
*969“Popular Radio” for the issue of July-August 1927 contains an article by James H. Knapp relating to a handy setup for testing new circuits. The receiver consisted of a tuner and a two-stage amplifier. Knapp refers to a new detector circuit with which he was experimenting at the time, and says that it is a short-wave tuner capable of bringing in the stations that broadcast on the wave lengths around and below 100 meters. There are three switch elements which, when thrown to the left, put the antenna, the amplifier, and the A battery in operation with the new detector. When thrown to the right, the new detector circuit is cut out entirely and the standard detector hookup is placed in circuit.
With this two-path receiver the user is enabled to cover broadcast wave bands from 40 up to 550 meters.
This Knapp reference bears directly on the Bresson claims. The only difference, for example, between the Knapp device and that defined by Bresson in claim 10, is that Knapp switches the antenna from the receiving path not in use to the receiving path that is in use, whereas Bresson leaves his antenna permanently connected to both paths. Hogan found the Knapp arrangement more desirable, for he said that it is preferable to switch the antenna from one path to the other, because, when the two paths are permanently connected and parallel, the smaller coil tends to rob the signal energy from the other coil, and “consequently the signals that would be received on the longer wave path are not as strong as they would be if the short wave coil were disconnected.”
“Popular Radio” for March, 1926, has an article by Silver and Cockaday on “How to Build the S-C Receiver for Short and Long Waves.” It is stated that the receiver covers wave length ranges from 50 to° 550 meters. The authors say that the long tuning range of the receiver is accomplished by the use of special low capacity plug-in coil units. “Thus, with two standard A type inductances, the wave length range is from 190 to 550 meters. The range with two type B inductances is from 90 to 210 meters; the range with two type C inductances is from 50 to 110 meters.” Then reference is made to the reception for higher wave lengths and the employment of inductances, one that will' cover a range from 550 meters to 1,200 meters, another from 1,200 meters to 1,-800 meters. Comparing the defendant’s receiver with the receiver described in the Silver and Cockaday article, the essential point of difference is in the plug-in coil arrangement of the latter as compared with the multiple switch arrangement of the defendant’s devices. Both devices show the use of a common antenna, the use of common tubes always lighted and always having the plate voltage connected to them while the sets are in use; the use of common tuning condensers, the use of switches (coils as has been indicated in the case of the Silver and Cockaday device), a common audio amplifier, a common translator, and a common power source for all bands.
“Radio News” for November, 1925, contains an article by Sylvan Harris entitled “A New Two-Range Receiver.” This article shows another coil-changing method for switching the wave band of a multiple tube tuned radio frequency receiv'er. The writer says: “Each of the tuned R F secondary coils is tapped at a convenient point, depending upon how one wishes to speed up the range, and all of these tapping switches are controlled simultaneously by the same lever or rod.” Again: “The idea is subject to many variations, as one may imagine, and furthermore may be applied to many types of receivers where switching or tapping is feasible.” He refers to the tuning range of his receiver as divided into two bands, one from 130 to 170 meters, and the other from 350 to 750 meters.
United States letters patent No. 1,727,-641, issued September 10, 1929, to A. H. Grebe on an application filed January 30, 1926, refers to a frequency range extension switch. This embodies the same principle as the Harris article.
“Wireless World” for November 16, 1927, contains an article on “Long and Short Waves,” which refers to a growing tendency on the part of set manufacturers to provide a switch change-over from one to the other. Switching connections for wave band change in a typical radio high frequency amplifier detector receiver are set forth. This receiver covers two wave bands. Connection and disconnection are accomplished by a pair of switches,
“Radio” for July, 1926, contains an article by Doran on an all-wave duplex receiver. The writer, with more or less *970modesty, by way of prophecy, states that “the present receiver was developed after a year or more of experimenting and it is believed to be about the last word in ship sets.” This receiver was designed primarily for use aboard ship. All wave lengths are covered from 20 to 20,000 meters, including “amateur and radio cast short wave bands, regular radio cast bands, commercial ship bands, commercial and Navy long wave bands.” This is a three-channel receiver. One, circuit permits the reception on 600 meters through a length of 200 to 600 meters. A medium wave set employs a single circuit with tickler range regeneration control. Range 400 to 4,000 meters. A third circuit covers the range of from 4,000 to 20,000 meters.
Fig. 1 shows an arrangement of the three units and Fig. 2 shows how those units are associated with a single antenna and ground connection, with a set of batteries and phones. The circuits are shown in Figs. 6, 7, and 8.
The Doran receiver is of the multiple’ path type in which each path is tuned to a wave band that is different from the other path. There is an overlapping of bands, and in this respect the Doran receiver differs from the Bresson; also Doran has three receiver units instead of two. Fundamentally the principle of operation is the same in both.
An article in the “Wireless World and Radio Review” for June 8, 1927, by A. J. Bull, relates to a two-range all station receiver. A three-unit set covering the entire broadcast band is described. The instrument consists of three units which are contained in one cabinet and connected to form, so the description says, a receiver complete in every detail covering a range from 200 to 2,000 meters.
The unit A, which is the short-wave amplifier covering the normal broadcast band of wave lengths, consists of two high frequency valves transformer coupled, the primary winding of which is tapped for neutralizing purposes, aerial coil, and three variable condensers, together with associated equipment. The tuning range of this unit is 200 to 600 meters.
The second, or unit B, is the long-wave amplifier consisting of two valves with associated coils, variable condensers, and other necessary equipment. The range is 600 to 2,000 meters.
The third, unit C, consists of three valves, one detector, and two amplifying at low frequency, together with transformers, jacks, etc.
Two double-poled change-over switches are shown. The two switches are linked together by a rod. By pushing the rod slightly into the cabinet, the aerial and earth connections are transferred from the lower H. F. unit to the top one of the detector valve disconnected from the lower unit and connected to the upper one. The author says: “Consequently, if unit 'A is tuned to say Hamburg (395 metres) and unit B to Radiola, Paris (1750 metres), a rapid change from one to the other can be effected by slightly moving the rod into or out of the cabinet as required.”
In addition to this rich prior art, the defense of aggregation is raised to invalidate the patent. As early as 1923 or 1924 commercial receivers for short-wave reception were on the market. These were known as the “Radiola 2” and “Radiola 4,” and, of course, receivers for reception for the long-wave band were also in the market. Indeed, as the plaintiffs’ brief admits, “plaintiffs make no claim to the novelty of either of the circuits of the Bresson patent separately.”
• Given two devices, one comprising an antenna short-wave amplifying and detecting means, a source of power and a loudspeaker, and another device for receiving long radio waves, comprising an antenna long-wave amplifying and detecting means, a source of power, a loud-speaker, the addition of a switch capable of connecting the loud-speaker to one or the other of the devices and disconnecting that not in use, and the employment of but one source of power, would call for engineering skill rather than invention.
But invalidity need not rest on that ground. It can readily be predicated on the prior art. The combination of the claims, excepting only the vacuum tubes and the functions peculiar to them, is found in the 1914 Navy receiver. ” The 1919-1920 "Navy use did disclose the device with radio frequency amplification and detection. Certainly no invention can be predicated over the Riverhead use in 1924 nor over the Knapp disclosure. The art shows - every element of the Bresson claims with the same functional arrangement and with the same functional results.
Holding the patent, as I do, invalid, it is not necessary to pass on the question of infringement.
*971If this opinion is not in sufficient compliance with the rule requiring findings of fact and conclusions of law, submit findings of fact and conclusions of law in accordance therewith.