Definition

A. GENERAL STATEMENT OF THE CLASS SUBJECT MATTER

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 and within this class

SYSTEM AND NETWORKS INCLUDING TWO OR MORE OF THE NETWORKS AS DEFINED 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 OUTPUT CIRCUIT

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 GENERIC TO THE SUBJECT MATTER OF THIS CLASS

See References to Other Classes below.

WAVE TRANSMISSION LINE AND NET WORKS ANALOGOUS TO THOSE IN THIS CLASS, BUT WHICH ARE CLASSIFIED ELSEWHERE

See References to Other Classes.

TESTING AND MEASURING SYSTEMS FOR WAVE TRANSMISSION LINES AND NETWORKS

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.