|  | H |
SECTION H — ELECTRICITY

|  | H03 |
BASIC ELECTRONIC CIRCUITRY

|  | H03H |
IMPEDANCE NETWORKS; RESONANT CIRCUITS; RESONATORS (measuring, testing Fulltext... Hierarchy... Expanded...G01R; impedance networks or resonators comprising of distributed impedance elements only i.e. of the waveguide type, Fulltext... Hierarchy... Expanded...H01P; networks specially designed for coupling between the active elements in an amplifier, e.g. wide-band coupling networks, Fulltext... Hierarchy... Expanded...H03F; networks for modifying the frequency characteristics of communication cables, e.g. equalising networks, Fulltext... Hierarchy... Expanded...H04B 3/14)

|  | H03H |
Note(s) This sub-class deals with (a) networks comprising lumped impedance elements; (b) networks comprising distributed impedance elements together with lumped impedance elements; (c) networks comprising electromechanical or electro-acoustic devices; (d) networks simulating reactances and comprising discharge tubes or semiconductor devices, and (e) constructions of electromechanical resonators.

|  | H03H 1/00 |
Constructional details of impedance networks whose electrical mode of operation is not specified or applicable to more than one type of network

|  | H03H 3/00 |
Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators

|  | H03H 3/02 |
· | for the manufacture of piezo-electric or electrostrictive resonators

|  | H03H 3/04 |
· · | for obtaining desired frequency or temperature coefficient

|  | H03H 3/06 |
· | for the manufacture of magnetostrictive resonators

|  | H03H 5/00 |
One-port networks (comprising electromechanical devices Fulltext... Hierarchy... Expanded...H03H 9/00; networks simulating the impedance of a communication cable, e.g. for balancing purposes, Fulltext... Hierarchy... Expanded...H04B 3/00)

|  | H03H 5/02 |
· | with no voltage- or current-dependent elements

|  | H03H 5/04 |
· · | comprising only non-adjustable elements

|  | H03H 5/06 |
· · · | Resonant circuits, i.e. consisting of lumped inductance and capacitance

|  | H03H 5/08 |
· · | comprising at least one adjustable element (tuning of resonant circuits Fulltext... Hierarchy... Expanded...H03J)

|  | H03H 5/10 |
· · | comprising at least one element with prescribed temperature coefficient

|  | H03H 5/12 |
· | with at least one voltage- or current-dependent element

|  | H03H 7/00 |
Multiple-port networks (comprising electromechanical devices Fulltext... Hierarchy... Expanded...H03H 9/00; comprising distributed impedance elements Fulltext... Hierarchy... Expanded...H03H 13/00; receiver input circuits Fulltext... Hierarchy... Expanded...H04B 1/18; networks simulating a length of communication cable Fulltext... Hierarchy... Expanded...H04B 3/40)

|  | H03H 7/02 |
· | Frequency-selective networks with non-adjustable characteristics

|  | H03H 7/04 |
· · | with only passive elements as essential network components

|  | H03H 7/06 |
· · · | with resistors and either capacitors or inductors

|  | H03H 7/08 |
· · · | Bandpass filters consisting of two or more coupled tuned circuits

|  | H03H 7/10 |
· | Frequency-selective networks with adjustable characteristics (automatic adjustment of filters Fulltext... Hierarchy... Expanded...H03G 5/16; tunable bandpass filters Fulltext... Hierarchy... Expanded...H03J)

|  | H03H 7/12 |
· · | Bandpass filters with adjustable bandwidth and fixed centre frequency (automatic bandwidth control in receivers Fulltext... Hierarchy... Expanded...H03G 5/16)

|  | H03H 7/14 |
· | Networks for modifying shape of frequency characteristics of a transmission path (tone control circuits Fulltext... Hierarchy... Expanded...H03G 5/00; for communication cables Fulltext... Hierarchy... Expanded...H04B 3/14)

|  | H03H 7/16 |
· · | the network being continuously adjustable

|  | H03H 7/18 |
· | Networks for phase shifting

|  | H03H 7/20 |
· · | continuously adjustable

|  | H03H 7/22 |
· · · | with provision for adjusting the attenuation also

|  | H03H 7/24 |
· | Frequency-independent attenuators

|  | H03H 7/26 |
· · | comprising resistors only

|  | H03H 7/28 |
· | Time domain networks, i.e. networks having an impulse response which approximates a prescribed function of time, e.g. matched filter

|  | H03H 7/30 |
· | Time-delay networks

|  | H03H 7/32 |
· · | with lumped inductance and capacitance

|  | H03H 7/34 |
· · | with lumped and distributed reactance

|  | H03H 7/36 |
· · | with delay time continuously adjustable

|  | H03H 7/38 |
· | Impedance-matching networks

|  | H03H 7/40 |
· · | Automatic matching of load impedance to source impedance

|  | H03H 7/42 |
· | Balance-unbalance networks

|  | H03H 7/44 |
· | Networks comprising gyrators

|  | H03H 7/46 |
· | Networks for connecting several sources or loads, working on different frequencies, to a common load or source (for use in multiplex transmission systems Fulltext... Hierarchy... Expanded...H04J 1/00)

|  | H03H 7/48 |
· | Networks for connecting several sources or loads, working on the same frequency to a common load or source (hybrid circuits for two-way transmission Fulltext... Hierarchy... Expanded...H04B)

|  | H03H 7/50 |
· · | for obtaining two output voltages having a phase difference substantially independent of frequency

|  | H03H 7/52 |
· | One-way transmission networks (Fulltext... Hierarchy... Expanded...H03H 7/44 takes precedence)

|  | H03H 9/00 |
Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators (Fulltext... Hierarchy... Expanded...H03H 13/00 takes precedence; making crystals Fulltext... Hierarchy... Expanded...B01J 17/00; selection of materials thereof Fulltext... Hierarchy... Expanded...H01V; electromechanical transducers Fulltext... Hierarchy... Expanded...H04R)

|  | H03H 9/02 |
· | Details of resonators

|  | H03H 9/04 |
· · | Holders; Driving means, e.g. electrodes, coils; Supports

|  | H03H 9/06 |
· · · | Adjustable, elastic, or damping electrodes or supporting means

|  | H03H 9/08 |
· · · | Holders with means for regulating temperature

|  | H03H 9/10 |
· · · | Mounting resonators in sealed enclosures

|  | H03H 9/12 |
· · · · | for luminous resonators

|  | H03H 9/14 |
· | Constructions of single resonators consisting of piezo-electric or electrostrictive material

|  | H03H 9/16 |
· · | with two electrodes

|  | H03H 9/18 |
· · · | consisting of quartz

|  | H03H 9/20 |
· · | with more than two electrodes

|  | H03H 9/22 |
· | Constructions of single resonators consisting of magnetostrictive material

|  | H03H 9/24 |
· | Constructions of single resonators, consisting wholly or partially of material which is not piezo-electric, electrostrictive, or magnetostrictive

|  | H03H 9/26 |
· | Structural combinations of mechanically coupled resonators

|  | H03H 9/28 |
· · | Combinations of a piezo-electric or electrostrictive resonator and a magnetostrictive resonator

|  | H03H 9/30 |
· | Constructions of delay lines

|  | H03H 9/32 |
· | Networks comprising piezo-electric or electrostrictive resonators and no other resonators

|  | H03H 9/34 |
· | Networks comprising magnetostrictive resonators and no other resonators

|  | H03H 11/00 |
Networks simulating reactances and comprising discharge tubes or semiconductor devices

|  | H03H 13/00 |
Networks comprising distributed impedance elements, e.g. cavity resonators, together with lumped impedance elements (time-delay networks Fulltext... Hierarchy... Expanded...H03H 7/30)