1. This class includes electric wave transmission systems wherein electromagnetic wave energy is guided or constrained by a wave transmission device of the long line type other than loaded lines.
2. Included are passive wave transmission networks simulating the characteristics of a long line wave transmission systems or wave guides, such as artificial lines, delay networks, resonators, impedance matching networks, equalizers, wave filters and transmission line terminations.
3. Also included are passive coupling networks and terminating networks having either lumped or distributed electrical circuit parameters and having impedance characteristics peculiarly adapted for use with the wave transmission systems of paragraph 1, above, or which are designed to be frequency responsive, or which are designed to
be effective over or within a range of frequencies, for example, impedance matching networks, hybrid networks, coupling networks, wave shaping networks, phase shifting networks, wave filters, equalizers and attenuators.
4. Smoothing type wave filters having shunt capacitance, or series inductance, or both, usually designed to pass direct current and to reduce the effect of any undesired alternating or pulsating current superimposed on the direct current, or to pass direct current and low frequency alternating current or pulsating current and to reduce the effect of an undesired higher frequency alternating or pulsating current.
5. Networks including a wave transmission device and means for decreasing the amplitude range of the signal applied to the transmission device as the signal increases in amplitude and means for increasing or restoring the amplitude range of the signal after the transmission over the transmission device (i.e., companders).
6. Passive networks for producing an output wave which is the time derivative or time integral of the input wave (i.e., differentiating or integrating systems).
7. Systems including active elements for producing across at least two of the system terminals a negative resistance, and/or an inductance, or capacitance which may be positive or negative. 8. Wave traps using long line elements.
9. Transmission systems including only one or more of the systems or networks defined in paragraphs 1 - 8, above, and such systems in combination with current or voltage magnitude control means of the passive type. Systems including two or more of the networks or systems defined in paragraphs 1 - 8, above, are classified as set forth in the Class Definition, subsection C, below.
10. Components and elements not constituting a complete system or network limited by claimed structure to use in the systems or network of paragraph 1, above, and not otherwise classified, and also long line elements.
B. ACTIVE NETWORK
The systems classified in this class ordinarily contain no active elements, the only exceptions being the amplitude compression and expansion systems (companders) and negative resistance and/or reactance networks of the active element type found in this class. See Subclass References to the Current Class, below.
LINES WITH OTHER CLASSES
SYSTEM AND NETWORKS INCLUDING TWO OR MORE OF THE NETWORKS ASDEFINED IN 1 - 8 OF THE CLASS DEFINITION
Such systems and networks which include two or more of the networks or systems so that each has its own function, and one is not merely part of the other, are classified in the first occurring subclass and cross-referenced to the later occurring subclass or subclasses. For instance, a filter (subclasses 167+) combined with a wave shaper (subclass 20) is classified in subclass 20 and cross-referenced to subclasses 167+. Where the combinations of the plural networks are useful as a third device having its own function provided for in the schedule, the patent is classified in the subclass providing for the third device. For example, the combination of a resonator (subclasses 219+) and a long line (subclasses 236+) which results in an interference elimination device (subclass 12) would be classified in subclass 12 and cross-referenced to subclasses 219+ and 236+ for novel resonator or long line structure if necessary. Where one of the networks is only a part of another network, the patent is classified on the basis of the combination and cross-referenced if necessary for the part. For example, a filter (subclasses 167+) including a long line element with impedance matching (subclass 32) where the over-all function of the network is filtering and not impedance matching, is classified in subclasses 202+ and cross-referenced to subclasses 33+ if necessary.
NETWORKS AND SYSTEMS WITH SPECIFIC SOURCE OF INPUT ENERGY
This class does not provide for the subject matter of the class (Class Definition paragraphs 1-10 above) in combination with a specific source of electromagnetic wave energy, such as a microphone, which limits the system to use with a particular art even though the source is recited by name only. However, this class will take the systems and networks of the class in combination with a source of wave energy which is recited by its characteristics; for example, as being composed of a band of frequencies with only odd harmonics, or where the source is recited only as a general class of wave energy generators, such as an oscillator, etc., where the specific characteristics and details of the source are recited, such as specific oscillator system details, the system or network is classified with the specific source.
NETWORKS AND SYSTEMS WITH SPECIFIC LOADS IN THE OUTPUTCIRCUIT This class does not provide for the subject matter of the class (Class Definition, paragraphs 1 to 10 above) in combination with a specific load device supplied with energy by the system or network, even though the load device is recited by name only (as a motor, loudspeaker, piezoelectric crystal, etc.). Such systems and networks are classified with the art which provides for the systems of supply for the specific load device.
SYSTEMS AND NETWORKS AND COMPONENTS IN OTHER CLASSES GENERICTO THE SUBJECT MATTER OF THIS CLASS
See References to Other Classes below.
WAVE TRANSMISSION LINE AND NET WORKS ANALOGOUS TO THOSE INTHIS CLASS, BUT WHICH ARE CLASSIFIED ELSEWHERE
See References to Other Classes.
TESTING AND MEASURING SYSTEMS FOR WAVE TRANSMISSION LINES ANDNETWORKS
This class (333) will take systems for determining the electrical wave propagation characteristics of transmission lines and networks falling within the class definition, provided that significant details of the transmission line or network are claimed. That is, merely claiming the line or network by name only (e.g., as a transmission line, coupling network or resonator) or characterizing it as a four terminal or two terminal impedance network would not be sufficient basis for classification in this class, classification would then be in one of the classes indicated below, depending on the nature of the test or measurement.
1. Long Telephone Lines:
Systems and apparatus for testing long telephone lines to determine impedance irregularities, unbalance in loaded lines, impedance versus frequency characteristics, impedance versus delay characteristics, or other long telephone line characteristics are classified elsewhere. See References to Other Classes, below
2. Power, Voltage and/or Current Determination in Wave Transmission Lines or Networks:
Apparatus for measuring the voltage or current, or the voltage or current standing wave ratio, or power dissipation in wave transmission lines are classified in elsewhere. See References to Other Classes, below 3. Impedance Characteristic of Networks or Network Elements:
Systems for determining the inductance, capacitance or resistance, or any of these properties over a range of frequencies, of four-terminal or two-terminal impedance networks in general are classified in elsewhere. See References to Other Classes, below
4. Wave Frequency Determination Systems:
Wave frequency determination systems having means giving a direct quantitative indication of the frequency of electrical currents are classified elsewhere. See References to Other Classes, below.
Frequency meters which measure frequency by utilizing phase
shift networks are classified elsewhere. See References to Other Classes.
5. Wave Meters:
Wave Meters for determining the wave length of electrical waves are classified elsewhere.
6. Electromagnetic Radiation Field Strength Measurement:
Apparatus for measuring electromagnetic radiation field strength is classified elsewhere. See References to Other Classes.
7. Wave Analyzing Systems:
Devices for determining the individual frequency components of a complex electric wave, and such devices which also determine the amplitude or relative phase positions of the different frequency components of the complex wave are classified elsewhere. See References to Other Classes. Speech wave analyzing devices are classified elsewhere. See References to Other Classes.
CONDUCTOR STRUCTURE, ARRANGEMENTS AND COMPONENTS
See References to Other Classes below..
SYSTEMS UTILIZING WAVE TRANSMISSION LINES AND NETWORKS
See References to Other Classes.
SEE OR SEARCH THIS CLASS, SUBCLASS:
1+, for plural channel systems wherein passive means, such as wave filters, are employed to separate plural messages or signals.
14, for amplitude compression and expansion systems (companders).
213+, for negative resistance and/or reactance networks of the active element type.
REFERENCES TO OTHER CLASSES
SEE OR SEARCH CLASS
84, Music, 661, 699 or 736 for electrical tone generating and music instruments with electric translating devices including coupling networks or wave filters. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks)
138, Pipes and Tubular Conduits, appropriate subclasses for conduits (including wave guides) and conduit and pipe accessories disclosed for electrical use even though the conduit is made of or lined with metal or insulating material unless there is claimed some structure or feature which limits the same to electrical use in addition to mere pipe or conduit structure. (See Lines With Other Classes, "Systems and Networks and Components in Other Classes Generic to the Subject Matter of This Class")
138, Pipes and Tubular Conduits, provides for conduit and pipe structure and accessories. See Lines With Other Classes, "Systems and Networks and Components in Other Classes, Generic to the Subject Matter of This Class (and related class references) above. (See Lines With Other Classes, "Conductor Structure, Arrangements and Components")
174, Electricity: Conductors and Insulators, appropriate subclasses for housings, conductor and conduit structure and for conductor and conduit joint and end structure which include electrical features and which are not defined as having long line characteristics, and
137+, for insulator structures. See subclasses 32+ for conductor arrangements and structures for preventing or reducing the detrimental effects due to either the self-inductance of a single conductor or mutual inductance between plural conductors, subclasses 27 and 113+ for parallel or twisted conductor structure, subclasses 28+ and 102+ for coaxial and shielded cable structure, subclasses 37+ for underground conductor structure, subclasses 38, 43, 49, and 71+ for branched electrical conductor structure, and subclasses 40+ for overhead conductor structure. (See Lines With Other Classes, "Systems and Networks and Components in Other Classes Generic to the Subject Matter of This Class")
174, Electricity: Conductors and Insulators, provides for conductor structure, insulator structure and transmission accessories (e.g., boxes, shields, housing). (See Lines With Other Classes, "Conductor Structure, Arrangements and Components")
178, Telegraphy,
45, provides for loaded lines and all systems and networks analogous to the systems or networks in this class (333) which include loaded lines. Subclasses 69+ includes patents relating to line clearing, circuit maintenance and anti-inductive lines analogous to similar systems in subclass 12 of Class 333. (See Lines With Other Classes, "Wave Transmission Line and Net Works Analogous to Those in This Class, etc.")
178, Telegraphy,
46, provides for loading coils for use with loaded lines. (See Lines With Other Classes, "Conductor Structure,
Arrangements and Components") 178, Telegraphy, for telegraph systems utilizing wave transmission lines and networks, especially
43, for space induction radiation systems, subclasses 45+ for loaded transmission line systems; subclass 49 for systems wherein currents (signaling or otherwise) and telegraph signal currents are superposed on the same transmission path, subclass 63 for cable systems including means for correcting for telegraph signal distortion caused by cable capacitance; subclass 64 for wave transmission line systems including mutual induction type coupling networks or transformers; subclasses 66.1+ for alternating current systems, other than harmonic or vibrating reed systems (for which see subclass 47); subclasses 66.1+ for pulsating current systems; and subclass 69 for telegraph systems wherein wave transmission networks are utilized to correct for the deleterious effects of line charges and surges which may cause signal distortion. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
191, Electricity: Transmission to Vehicles,
2+, for electrical transmission line systems and coupling means for transmitting electric current between relatively movable source and load and subclass 10 for systems wherein the transmission of energy between the relatively movable source and load is effected through an induction field coupling means. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
200, Electricity: Circuit Makers and Breakers, appropriate subclasses for electric switches of general utility and not limited by claimed structure to use with long lines. (See Lines With Other Classes, "Systems and Networks and Components in Other Classes Generic to the Subject Matter of This Class")
200, Electricity: Circuit Makers and Breakers, provides for electric switches (See Lines With Other Classes, "Systems and Networks and Components in Other Classes, Generic to the Subject Matter of This Class (and related class references) above). (See Lines With Other Classes, "Conductor Structure, Arrangements and Components")
219, Electric Heating, wherein wave transmission lines or coupling networks are employed in electrical heating systems. Note
600+, for inductive heating, subclasses 678+ for microwave heating, and subclasses 764+ for capacitive dielectric heating, subclasses 50+, especially subclasses 108+ and 130.1+ for metal heating systems, and subclasses 482+ for electrical heating systems in general. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
246, Railway Switches and Signals, for wave transmission networks that may be employed in railway electric signaling and control, especially
7+, for train telegraphy and telephony used for train dispatching, subclass 30 for automatic block signal systems controlled by hertzian waves, subclass 61 for automatic block signal systems wherein the signal and propulsion currents are superimposed, subclass 63 for cab signal or train control systems wherein signals or control currents are transferred between the train and the transmission line by induction and subclasses 72, 81+ for systems wherein the signaling energy is derived from the propulsion current. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
250, Radiant Energy, 250, and in Class 324, Electricity: Measuring and Testing, subclasses 76.39+, especially subclasses 76.41+ and 76.51, for determining the wave length of electrical waves.
257, Active Solid-State Devices (e.g., Transistors, Solid-State Diodes),
661, 664. (See Lines With Other Classes, "Conductor Structure and Within This Class, Arrangements and Components")
307, Electrical Transmission or Interconnection Systems, for miscellaneous transmission or interconnection systems not otherwise classified. For example, Class 307 provides for subject matter similar to that classified in Class 323 where there are plural input circuits and/or plural output circuits. Class 307 also provides for some systems which include one or more long line elements where the system includes an active element so that the system is excluded from Class 333. See the pulse forming and wave shaping in
106+, for example. Class 307 is also the miscellaneous class for anti-inductive systems (see subclasses 89+). (See Lines With Other Classes, "Systems and Networks and Components in Other Classes Generic to the Subject Matter of This Class")
307, Electrical Transmission or Interconnection Systems,
147+, is the miscellaneous subclass for conductor arrangements or structure. (See Lines With Other Classes, "Systems and Networks and Components in Other Classes, Generic to the Subject Matter of This Class (and related class references) above). (See Lines With Other Classes, "Conductor Structure, Arrangements and Components")
307, Electrical Transmission or Interconnection Systems, is the generic place for electrical energy distributing and/or controlling and/or generating systems for which provision is not made in any other electrical system class. By way of
example, provision is made for
1+, for systems with superimposed unlike currents, subclasses 11+ for plural load systems, subclasses 43+ for plural supply circuits or sources, subclasses 401+ for semiconductor (i.e., transistor) electric or transductor system, subclasses 89+ for anti-induction or coupling to other systems, subclasses 326+ for self protective, safety or limit control systems, subclasses 98+ for combined impedance and switch systems, subclass 103 for line drop compensation, subclass 104 for electromagnet or highly inductive systems, subclass 105 for harmonic filtering or neutralizing systems, subclasses 106+ for wave form, wave shaping or pulse producing systems, subclasses 112+ for switching systems, subclasses 147+ for conductor arrangements or structure, and subclasses 149+ for miscellaneous systems. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
315, Electric Lamp and Discharge Devices: Systems, particularly
4+, for cathode-ray tubes having long line elements or resonators structurally combined therewith, subclass 39 for a space discharge device structurally combined with wave guide, coaxial cable or resonant parallel wire transmission line, and subclass 40 for space discharge devices with an electrode formed as an inductive impedance (e.g., magnetron). (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks") 323, Electricity: Power Supply or Regulation Systems, provides for miscellaneous transformer systems in
355, and for miscellaneous impedance systems in subclass 364, where the system or network has only a single input and a single output. Class 323 also provides for the miscellaneous systems for controlling the magnitude of the current and/or the voltage and/or for controlling the phase in systems and networks having only a single input and a single output circuit where the same current is in the output as is in the input. (See Lines With Other Classes, "Systems and Networks and Components in Other Classes Generic to the Subject Matter of This Class")
323, Electricity: Power Supply or Regulation Systems,
355, provides for the miscellaneous structural arrangement of a transformer and other electrical devices which are connected together, and subclass 364 provides for the miscellaneous structural arrangements of impedance elements, which are connected together to form a network. (See Lines With Other Classes, "Conductor Structure, Arrangements and Components")
324, Electricity: Measuring and Testing, for electrical testing systems utilizing wave transmission networks or for measuring impedance characteristics of electrical networks in
general,
72, 95, 140+, and 612+ for electric power, current and/or voltage measuring systems for systems employing wave transmission lines or networks for determining reflected power or standing wave amplitude ratios and subclasses 76.77+ for electric phase angle measuring systems including electric wave transmission lines or networks used for time delay or coupling purposes. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
324, Electricity: Measuring and Testing,
600+, for Systems for determining the inductance, capacitance or resistance, or any of these properties over a range of frequencies, of four-terminal or two-terminal impedance networks in general; subclasses 76.77+ for phase shift or phase relations between voltages or currents or voltage and current in electrical systems in general.
324, Electricity: Measuring and Testing,
76.12+, and 76.39+ for means giving a direct quantitative indication of the frequency of electrical currents.
324, Electricity: Measuring and Testing, 76.52+, for frequency meters which measure frequency by utilizing phase shift networks.
324, Electricity: Measuring and Testing,
76.11+, for apparatus for measuring electromagnetic radiation field strength.
324, Electricity: Measuring and Testing,
76.12+, for devices for determining the individual frequency components of a complex electric wave, and such devices which also determine the amplitude or relative phase positions of the different frequency components of the complex wave.
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, appropriate subclasses for miscellaneous nonlinear circuits which may utilize an active device such as a transistor or electron tube. (See Lines With Other Classes, "Systems and Networks and Components in Other Classes Generic to the Subject Matter of This Class")
327, Miscellaneous Active Electrical Nonlinear Devices, Circuits, and Systems, appropriate subclasses for miscellaneous circuits which may incorporate a transmission line device. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
329, Demodulators,
322, and 354+ for a demodulator with distributed electrical parameters. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
330, Amplifiers, appropriate subclasses, for one way amplifiers utilizing wave transmission networks or filters for input, output, or interstage coupling, particularly
53+, 116, 117, 120+, 122, 157+, 185+, and 192+. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks") 331, Oscillators, for oscillation generators utilizing wave transmission lines and networks as elements thereof, particularly
5, 6+, 9, 79+, 86+, 93, and 96+ for oscillator systems employing distributed parameter networks or resonators, subclasses 110 and 138+ for oscillators employing bridge networks, subclasses 86+, 115, 126+, and 132+ for oscillators of the negative resistance type, subclass 135+ for oscillators employing phase shift networks, subclasses 74+ for oscillators combined with a particular output coupling network and subclasses 73, 116, 139, and 154+ for oscillators employing an electromechanical resonator. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
332, Modulators, for modulation systems utilizing wave coupling networks, long line sections or negative impedance devices as elements thereof, particularly
129+, and 138+ under frequency modulators and subclasses 163+, 175 and 176+ under amplitude modulators. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
334, Tuners, provides for tuners which are closely analogous to the wave filters in this class. The tuners usually have inductance and capacitance elements of the lumped type together with means to vary either the inductance or capacitance element or both in order to change the mean resonant frequency of the tuner. The tuners in Class 334 may include one or more long line elements in addition to a lumped inductor or capacitor; or the tuner may consist of a distributed parameter type tuning unit which is adjusted in discrete, distinct steps; or where two or more distributed parameter type tuning units are ganged together either mechanically and/or electrically so as to have their mean resonant frequency adjusted in unison. Where only the band width of a filter is varied without varying the mean resonant frequency, classification is in this class (333). (See Lines With Other Classes, "Wave Transmission Line and Networks Analogous to Those in This Class, etc.", "Systems and Networks and Components in Other Classes, Generic to the Subject Matter of This Class"; "Conductor Structure, Arrangements and Components")
334, Tuners, appropriate subclasses for tuned networks for use in wave energy apparatus and comprising inductance and capacitance elements in circuit arrangement to form a resonant circuit and in which structure is provided for adjusting one or both of these elements for changing the mean resonant frequency of the circuit. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
336, Inductor Devices, appropriate subclasses for transformers and inductors which are not designed to be frequency responsive (e.g., not having points of resonance within the range of frequencies over which the device is designed to operate). (See Lines With Other Classes, "Systems and Networks and Components in Other Classes Generic to the Subject Matter of This Class; and "Conductor Structure, Arrangements and Components")
338, Electrical Resistors, appropriate subclasses, for fixed and variable electric resistors, per se. See (2) Note under Class 333,
22, for the distinction between the resistors in Class 338 and the dissipating terminals for long lines. (See Lines With Other Classes, "Systems and Networks and Components in Other Classes Generic to the Subject Matter of This Class)
338, Electrical Resistors, provides for fixed and variable resistors. (See Lines With Other Classes, "Systems and Networks and Components in Other Classes, Generic to the Subject Matter of This Class (and related class references) above). (See Lines With Other Classes, "Conductor Structure, Arrangements and Components)
340, Communications: Electrical, for electrical communication systems in general having wave transmission lines and networks as elements thereof, particularly 825.37+, for party line type selective systems, subclasses 825.57+ for pulse responsive selective systems, subclass 825.70 for phase responsive selective systems, subclasses 825.71+ for frequency responsive selective systems, subclasses 825.77+ for amplitude responsive systems, subclasses 870.01+ continuously variable indication systems (e.g., telemetering), subclasses 286+ for miscellaneous signaling systems, and subclasses 310.01+ for composite signaling systems (e.g., signal over power line).
343, Communications: Radio Wave, for radio wave energy systems which employ wave transmission lines and networks as elements thereof,
5+, for reflected or returned wave systems, (e.g., object detection radar), subclasses 350+ for directive systems (including polarization), subclasses 700+ for antennas involving wave transmission lines and networks including long
line sections, usually resonant, designed to act as space radiators or collectors of electromagnetic waves. See (11) Note under subclass 700 of Class 343 for classification lines between coupling networks and antennas with such coupling networks. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
360, Dynamic Magnetic Information Storage or Retrieval, for magnetic recorders or reproducers having wave transmission networks as elements thereof. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
361, Electricity: Electrical Systems and Devices,
271+, for capacitors, subclasses 600+ for miscellaneous arrangements for mounting two or more different circuit elements which are not in circuit arrangement (including printed circuits), and subclasses 503+ for electrolytic capacitors. (See Lines With Other Classes, "Conductor Structure, Arrangements and Components")
361, Electricity: Electrical Systems and Devices,
107+, for wave transmission networks for use in surge suppression circuits, and subclasses 117+ for lightning arresters. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
363, Electric Power Conversion Systems, particularly
2+, 9+ and 36 for phase conversion systems (e.g., m-phase to n-phase) combined with other types of conversion, subclasses 39+ for current conversion systems combined with means to eliminate undesired frequency components (e.g., filter), and subclasses 148+ for phase conversion systems, per se. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
364, Electrical Computers and Data Processing Systems, appropriate subclasses, (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks) 365, Static Information Storage and Retrieval, appropriate subclass for read/write static storage systems, particularly
194, 198, and 223 which include delay, transmission, and bridge means for a read/write circuit. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
367, Communication, Electrical: Acoustic Wave Systems and Devices,
197+, for selective systems which are sound responsive. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
370, Multiplex Communications, appropriate subclasses for multiplexing systems, particularly
272, for a sextuplex system, subclasses 273+ for a quadruplex system, subclasses 276+ for a duplex system, and subclass 297 for a diplex system. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
379, Telephonic Communications,
22+, for systems and apparatus for testing long telephone lines to determine impedance irregularities, unbalance in loaded lines, impedance versus frequency characteristics, impedance versus delay characteristics, or other long telephone line characteristics.
379, Telephonic Communications,
398, includes loaded line systems and anti-inductive systems analogous to the subject matter of this class (333). (See Lines With Other Classes, "Wave Transmission Line and Net Works Analogous to Those in This Class, etc.")
379, Telephonic Communications, 443+, provides for telephone induction coils. (See Lines With Other Classes, "Conductor Structure, Arrangements and Components")
379, Telephony, appropriate subclasses, especially
90+, for composite systems, employing wave transmission networks wherein voice signal systems are combined with other electrical systems, such as telegraph, power or lighting systems (Note that this class (333) provides for plural channel systems wherein passive means, such as wave filters, are employed to separate plural messages or signals. (See Subclass References to the Current Class, above)); subclass 78 for wave transmission networks used to compensate for or prevent detrimental effects on telephone systems of internal or external induction or radiation fields; subclass 79 for such systems under subclass 78, utilizing capacitive reactance for compensation and subclass 80, under subclass 78, wherein the compensation means comprises impedance coils; subclass 81, for telephone substation circuits employing wave coupling networks of the conjugate or Whetstone bridge type and/or balancing networks; subclass 82 for space induction radiation systems having wave transmission networks as elements thereof, subclasses 170+ for telephone repeaters (i.e., two-way amplifiers) utilizing hybrid networks and line balancing networks; subclasses 172+ for coupling devices of the induction coil type associated with telephone instruments; subclass 174 for anti-induction devices including wave transmission networks for preventing the undesirable effects of induction in telephone systems or instruments, other than those anti-induction devices in subscribers circuits, for which see subclasses 78+, 81; and
subclass 175 for testing devices utilizing wave transmission networks for telephone systems or devices, not particularly subclasses 175.3+ under subclass 175 for testing long telephone lines and associated apparatus.
395, Information Processing System Organization,
500.34+, for the simulation of electrical phenomenon.
439, Electrical Connectors, provides for miscellaneous connector structure (see
55+, for preformed or printed circuit arrangements involving only conductors and connector structure). (See Lines With Other Classes, "Conductor Structure, Arrangements and Components")
455, Telecommunications, appropriate subclasses for filters analogous to those in this class and forming an element of radio communication systems. (See Lines With Other Classes, "Wave Transmission Line and Net Works Analogous to Those in This Class, etc.")
455, Telecommunications,
334+, for miscellaneous circuitry and apparatus which are specialized to use with radio apparatus. (See Lines With Other Classes, "Conductor Structure, Arrangements and Components")
455, Telecommunications, 39+, provide for modulated carrier wave systems of general application; subclasses 91+ provide for transmitters employing wave transmission lines, wave guides and networks for coupling the transmitter to an antenna; subclasses 130+ for radio receiver coupling and selecting networks, see particularly subclasses 132+, 3.1+ and 272+ for plural channel systems; subclasses 280+ for means for coupling antennas to radio receivers; subclasses 150+ for frequency selection networks; subclass 307 for filter means for noise elimination; and subclasses 338+ for miscellaneous coupling means. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Networks")
150+, for high temperature (Tc 30 K) superconducting devices, and particularly subclasses 210+ for transmission line and networks, electrical energy storage devices, magnetic coils, wires, cable, etc. (See Lines With Other Classes, "Systems and Networks and Components in Other Classes Generic to the Subject Matter of This Class")
150+, for high temperature (Tc 30 K) superconducting devices, and particularly subclasses 210+ for transmission line and networks, electrical energy storage devices, magnetic coils, wires, cable, etc. (See Lines With Other Classes, "Wave Transmission Line and Net Works Analogous to Those in This Class, but Which Are Classified Elsewhere")
150+, for high temperature (Tc 30 K) superconducting devices, and particularly subclasses 210+ for transmission line and networks, electrical energy storage devices, magnetic coils, wires, cable, etc. (See Lines With Other Classes, "Conductor Structure, Arrangements and Components")
150+, for high temperature (Tc 30 K) superconducting devices, and particularly subclasses 210+ for transmission line and networks, electrical energy storage devices, magnetic coils, wires, cable, etc. (See Lines With Other Classes, "Systems Utilizing Wave Transmission Lines and Network"s)
704, Data Processing: Speech Signal Processing, Linguistics, Language Translation, and Audio Compression/Decompression,
200+, for speech wave analyzing devices. 708, Electrical Computers: Arithmetic Processing and Calculating,
818, for correlation or convolution with tapped delay line, and subclass 819 for electrical analog filtering devices.
GLOSSARY:
ACTIVE NETWORK
A network containing a source of energy, or a sink of energy (i.e., a device for absorbing or dissipating energy other than that accounted for by the resistance of the components of the networks). Merely dissipating the heat generated by a resistance will not cause the resistance to be an active element.
AMPLITUDE RANGE
The ratio of the highest amplitude to the lowest amplitude of an undulating wave.
AMPLITUDE RANGE COMPRESSOR
A nonlinear device having an input and an output, the amplitude range of the output wave being less than the amplitude range of the input wave.
AMPLITUDE RANGE EXPANDER
A nonlinear device having an input and an output, the amplitude range of the output wave being larger than the amplitude range of the input wave. ARTIFICIAL LINES
Networks for simulating impedance characteristics of a smooth or loaded electrically long transmission line over a frequency range.
ATTENUATOR
Devices and networks consisting of one or more elements which exhibit only a positive resistance effect and which reduce the intensity of the energy passing through the device by dissipation, (a) the elements being proportioned to permit a change in their value to control the energy loss while maintaining substantially constant input and/or output impedance of the device, and/or (b) the elements being proportioned to permit the device to be inserted in the circuit to provide an energy loss without introducing any reflections in the circuit, and/or (c) the elements being combined with a long line or long line element, and/or (d) the device or network having an impedance equal to the impedance of a specified long line, and/or (e) the device or network is claimed as being particularly modified for use over a frequency band so that its characteristics are particularly related to frequency.
BALANCED CIRCUIT
A circuit having its conductors electrically symmetrical with respect to a reference potential plane (e.g., ground). The potentials between the two sides and ground are equal and of opposite sign. For example, a horizontal two wire line may be a balanced line.
CHARACTERISTIC IMPEDANCE
The impedance which a long line or a long line element would have if it were infinitely long. A long line which is terminated in its characteristic impedance is not resonant.
COMPANDER
An amplitude range compressor connected to an amplitude range expander with or without an intervening transmission line so that the amplitude range of the input wave is first decreased in the compressor and then increased in the expander.
COUPLING NETWORKS (a) Networks including significant reactive structure for effecting the transfer of oscillatory energy from one circuit to another circuit and having attenuation and/or delay characteristics over a frequency range for attenuating and/or delaying in a predetermined manner wave energy passing therethrough, and/or providing an impedance match between the network and at least one of the circuits; (b) smoothing type wave filters having shunt capacitance, or series inductance, or both usually designed to pass direct current and to reduce the effect of any undesired alternating or pulsating current, or to pass direct current and low frequency alternating current or pulsating current and to reduce the effect of any undesired higher frequency alternating or pulsating current.
DELAY
Includes phase distortion and also includes the retardation of a single pulse with respect to time.
DELAY NETWORK
Networks including significant structure for retarding wave energy a predetermined period of time over a range of frequencies.
DISSIPATING TERMINATIONS: (FOR LONG LINES)
Networks specialized for use with and designed for connection to the end of a long line transmission line and including a resistive component for dissipating the wave energy propagated along the line and presenting an essentially resistive impedance to the line.
DISTRIBUTED PARAMETERS
When the impedance of a transmission device or line at the operating frequency or band of frequencies is due primarily to the parameters of the device or line itself, and in considering the inductance, capacitance and resistance of the device or line they must be considered as mixed together and spread out along the device or line rather than being considered as in separate discrete lumps or devices as in the case of simple series and parallel circuits, the transmission device or line ay be said to have distributed parameters. Examples of circuits with distributed parameters include telephone, telegraph and power lines for high frequency energy.
EQUALIZER
Networks with attenuation or attenuation and phase distortion characteristics which vary over a frequency range for use in a wave transmission system for modifying the attenuation or attenuation and phase characteristics of the wave energy as a function of frequency. FREQUENCY RESPONSIVE NETWORK
As the frequency of the applied energy changes over a band, the impedance of the network varies as a function of the frequency. Frequency responsive networks and devices are designed to obtain desired characteristics where a band of frequencies or different frequencies are involved.
HYBRID TYPE NETWORK
A network for coupling one wave transmission line to two or more wave transmission lines in such manner that there is a conjugate relation between at least two of these coupled transmission lines to prevent any interchange of energy between the conjugately related lines.
IMPEDANCE MATCHING NETWORK
Coupling networks which include one or more impedance elements construed or proportioned to substantially eliminate the reflected wave energy between the network and at least one of the connected circuits caused by impedance differences.
LOADED LINES
A long line to which lumped impedance elements, usually capacitors or inductors, are added at regularly spaced points along the length thereof, or to which an added impedance is applied in a continuous manner, as for example, by wrapping a strip of magnetic material about the line or device to increase the inductance of the line or device.
LONG LINE
A wave transmission device or line having distributed parameters and especially designed to propagate electrical wave energy where the wave length of the transmitted energy is relatively short when compared with the length of the transmission line or device. The impedance of a long line is practically fixed by the constants of the line itself. The length of the transmission line or device may be a multiple or a fraction of a wave length, e.g., 1/4, 1/2, etc., or otherwise have its length proportioned to the wave length of the energy with which it is to be used.
LONG LINE ELEMENT
A circuit element having distributed parameters, such as a resonator, or a wave guide. A long line element may be a part of a long line wave transmission device or used in a network with other circuit elements of the lumped parameter type, for example, as in the case of delay networks, impedance matching networks, wave filters. LUMPED PARAMETERS OR IMPEDANCES
When the impedance of a transmission line or device at the operating frequency may be considered as equivalent to devices concentrated at one point, and the parameters of the system including the line or device is not substantially independent of the load devices connected thereto, the transmission line or device may be said to have lumped parameters. Lumped impedances is also used to include devices such as capacitors, inductors, and resistors which have their impedance concentrated at the terminals thereof.
NETWORK
A network is made up of two or more resistances, inductances, capacities or mutual inductances connected together in some manner.
PASSIVE NETWORK
A network containing no source of energy and in which no energy is dissipated other than that accounted for the resistance of the components of the network.
PHASE DISTORTION
Results from different frequencies travelling with different velocities such that their relative arrival times differ from their relative starting times.
PHASE DISTORTION CHARACTERISTIC
Used to designate the change in displacement of different frequency components of a band of frequencies transmitted by a transmission device or network. For example, certain frequencies of the band will be retarded or advanced a different amount than other frequencies.
PHASE SHIFT Used to designate the change in phase relation between voltage and current of the same wave energy, or between the voltages or the currents of different wave energy of the same frequency.
RESONATOR
Devices comprising conductive enclosures, cavities, or wave transmission line sections of the two terminal type, and having distributed inductance and capacitance, the line sections being terminated in other than the characteristic impedance of the line sections, the devices presenting resonant characteristics to the existing source of wave energy.
TAPERED LONG LINE
A long line having a physical dimension which changes
progressively in the direction of wave propagation along the line.
TRANSMISSION LINE
As used in the subclass definitions is synonymous with wave transmission devices.
UNBALANCED CIRCUIT
A circuit having its conductors electrically unsymmetrical with reference to a potential plane. For example, a concentric line is ordinarily unbalanced, the outer conductor being ordinarily connected to ground.
WAVE ENERGY
An undulatory disturbance propagated through a medium, (usually periodic in nature), its displacement varying periodically with respect to time or distance or both. The wave may be manifested in electrical, mechanical or acoustical form. However, in this class the term "wave energy" refers only to electrical wave energy. WAVE FILTER
Coupling networks which include significant structure permitting free transmission of electric waves of a single frequency or band of frequencies (which may include zero frequency) while attenuating substantially electric waves having other frequencies, or attenuating substantially electric waves of a single frequency or band of frequencies (which may include zero frequency) while permitting free transmission of electric waves having other frequencies.
WAVE GUIDE
A transmission device designed to propagate electrical waves having an electric or magnetic field component extending in the direction of propagation. The wave guide may be a hollow dielectric or metal tube, or a solid dielectric rod, the wave energy being propagated along the interior of the tube or rod and confined by the walls of the tube or rod.
WAVE PROPAGATION CHARACTERISTIC
Effect of the impedance characteristic of the transmission device upon the wave energy propagated by the transmission device, (e.g., the effect of transmission device or network to change the amplitude, phase of or delay in transmission as a function of frequency). Changes in the impedance parameters of the transmission device or in impedances associated therewith change the wave propagation characteristics of the transmission device.
WAVE SHAPING
Passive networks for modifying an electrical wave passing therethrough so that the amplitude-time characteristic of the output wave is different from that of the input wave and which have no function classified in other classes.
WAVE TRANSMISSION DEVICE
Any device which is used to guide or constrain electrical wave energy and to convey the energy from one place to another. Included are conductors, wave guides, resonant structures (e.g., cavities, etc.)
WAVE TRANSMISSION SYSTEM One of more wave transmission devices with or without appropriate coupling networks or transmission line characteristic modifying means arranged to convey electrical energy from one or more places to one or more other physically separated places. The system may be arranged so that different electrical energies may be conveyed in different directions at the same or different times over the system.
WAVE TRAP
A resonant circuit designed to exclude the energy of one particular frequency. It is analogous to a filter which is used to block one frequency and to pass other frequencies. It usually has circuit components equivalent to a filter, but may be used only to exclude energy of a particular frequency from a circuit.