|  | H |
SECTION H — ELECTRICITY

|  | H |
Note(s) These Notes cover the basic principles and general instructions for use of section H. Section H covers: basic electric elements, which cover all electric units and the general mechanical structure of apparatus and circuits, including the assembly of various basic elements into what are called printed circuits and also cover to a certain extent the manufacture of these elements (when not covered elsewhere); generation of electricity, which covers the generation, conversion and distribution of electricity together with the controlling of the corresponding gear; applied electricity, which covers: general utilisation techniques, viz. those of electric heating and electric lighting circuits; some special utilisation techniques, either electric or electronic in the strict sense, which are not covered by other sections of the Classification, including: electric light sources, including lasers; electric X-ray technique; electric plasma technique and the generation and acceleration of electrically charged particles or neutrons; basic electronic circuits and their control; radio or electric communication technique; the use of a specified material for the manufacture of the article or element described. In this connection, paragraphs 88 to 90 of the Guide should be referred to. In this section, the following general rules apply: Subject to the exceptions stated in I(c), above, any electric aspect or part peculiar to a particular operation, process, apparatus, object or article, classified in one of the sections of the Classification other than section H, is always classified in the subclass for that operation, process, apparatus, object or article. Where common characteristics concerning technical subjects of similar nature have been brought out at class level, the electric aspect or part is classified, in conjunction with the operation, process, apparatus, object or article, in a subclass which covers entirely the general electrical applications for the technical subject in question; The electrical applications referred to under (a), above, either general or particular, include: the therapeutic processes and apparatus, in class Fulltext... Hierarchy... Expanded...A61; the electric processes and apparatus used in various laboratory or industrial operations, in classes Fulltext... Hierarchy... Expanded...B01 and Fulltext... Hierarchy... Expanded...B03 and in subclass Fulltext... Hierarchy... Expanded...B23K; the electricity supply, electric propulsion and electric lighting of vehicles in general and of particular vehicles, in the subsection "Transporting" of section B; the electric ignition systems of internal-combustion engines, in subclass Fulltext... Hierarchy... Expanded...F02P, and of combustion apparatus in general, in subclass Fulltext... Hierarchy... Expanded...F23Q; the whole electrical part of section G, i.e. measuring devices including apparatus for measuring electric variables, checking, signalling and calculating. Electricity in that section is generally dealt with as a means and not as an end in itself; All electrical applications, both general and particular, presuppose that the "basic electricity" aspect appears in section H (see I(a) above) as regards the electric "basic elements" which they comprise. This rule is also valid for applied electricity, referred to in I(c), above, which appears in section H itself. In this section, the following special cases occur: Among the general applications covered by sections other than section H, it is worth noting that electric heating in general is covered by subclasses Fulltext... Hierarchy... Expanded...F24D or Fulltext... Hierarchy... Expanded...F24H or class Fulltext... Hierarchy... Expanded...F27, and that electric lighting in general is partly covered by class Fulltext... Hierarchy... Expanded...F21, since in section H (see I(c), above) there are places in Fulltext... Hierarchy... Expanded...H05B which cover the same technical subjects; In the two cases referred to under (a), above, the subclasses of section F, which deal with the respective subjects, essentially cover in the first place the whole mechanical aspect of the apparatus or devices, whereas the electrical aspect, as such, is covered by subclass Fulltext... Hierarchy... Expanded...H05B; In the case of lighting, this mechanical aspect should be taken to cover the material arrangement of the various electric elements, i.e., their geometrical or physical position in relation to one another; this aspect is covered by subclass Fulltext... Hierarchy... Expanded...F21V, the elements themselves and the primary circuits remaining in section H. The same applies to electric light sources, when combined with light sources of a different kind. These are covered by subclass Fulltext... Hierarchy... Expanded...H05B, whereas the physical arrangement which their combination constitutes is covered by the various subclasses of class Fulltext... Hierarchy... Expanded...F21; As regards heating, not only the electric elements and circuitry designs, as such, are covered by subclass Fulltext... Hierarchy... Expanded...H05B, but also the electric aspects of their arrangement, where these concern cases of general application; electric furnaces being considered as such. The physical disposition of the electric elements in furnaces is covered by section F. If a comparison is made with electric welding circuits, which are covered by subclass Fulltext... Hierarchy... Expanded...B23K in connection with welding, it can be seen that electric heating is not covered by the general rule stated in II, above.

|  | H03 |
BASIC ELECTRONIC CIRCUITRY

|  | H03D |
DEMODULATION OR TRANSFERENCE OF MODULATION FROM ONE CARRIER TO ANOTHER (masers, lasers Fulltext... Hierarchy... Expanded...H01S; circuits capable of acting both as modulator and demodulator Fulltext... Hierarchy... Expanded...H03C; details applicable to both modulators and frequency-changers Fulltext... Hierarchy... Expanded...H03C; demodulating pulses Fulltext... Hierarchy... Expanded...H03K 9/00; transforming types of pulse modulation Fulltext... Hierarchy... Expanded...H03K 11/00; coding, decoding or code conversion, in general Fulltext... Hierarchy... Expanded...H03M; repeater stations Fulltext... Hierarchy... Expanded...H04B 7/14; demodulators adapted for digitally modulated-carrier systems Fulltext... Hierarchy... Expanded...H04L 27/00; synchronous demodulators adapted for colour television Fulltext... Hierarchy... Expanded...H04N 9/66)

|  | H03D |
Note(s) This subclass covers only: demodulation or transference of signals modulated on a sinusoidal carrier or on electromagnetic waves; comparing phase or frequency of two mutually-independent oscillations.

|  | H03D |
Subclass index
DEMODULATION |
Amplitude; angle; combined; super-regenerative | 1/00; 3/00; 5/00, 9/00; 11/00
TRANSFERENCE | 7/00, 9/00
COMPARING PHASE OR FREQUENCY | 13/00
SUBJECT MATTER NOT PROVIDED FOR IN OTHER GROUPS OF THIS SUBCLASS | 99/00

P:50 |  | H03D 1/00 |
Demodulation of amplitude-modulated oscillations (Fulltext... Hierarchy... Expanded...H03D 5/00, Fulltext... Hierarchy... Expanded...H03D 9/00, Fulltext... Hierarchy... Expanded...H03D 11/00 take precedence)

|  | H03D 1/02 |
· | Details

|  | H03D 1/04 |
· · | Modifications of demodulators to reduce interference by undesired signals

|  | H03D 1/06 |
· · | Modifications of demodulators to reduce distortion, e.g. by negative feedback

|  | H03D 1/08 |
· | by means of non-linear two-pole elements (Fulltext... Hierarchy... Expanded...H03D 1/22, Fulltext... Hierarchy... Expanded...H03D 1/26, Fulltext... Hierarchy... Expanded...H03D 1/28 take precedence)

|  | H03D 1/10 |
· · | of diodes

|  | H03D 1/12 |
· · · | with provision for equalising ac and dc loads

|  | H03D 1/14 |
· | by means of non-linear elements having more than two poles (Fulltext... Hierarchy... Expanded...H03D 1/22, Fulltext... Hierarchy... Expanded...H03D 1/26, Fulltext... Hierarchy... Expanded...H03D 1/28 take precedence)

|  | H03D 1/16 |
· · | of discharge tubes

|  | H03D 1/18 |
· · | of semiconductor devices

|  | H03D 1/20 |
· · | with provision for preventing undesired type of demodulation, e.g. preventing anode detection in a grid detection circuit

|  | H03D 1/22 |
· | Homodyne or synchrodyne circuits

|  | H03D 1/24 |
· · | for demodulation of signals wherein one sideband or the carrier has been wholly or partially suppressed

|  | H03D 1/26 |
· | by means of transit-time tubes

|  | H03D 1/28 |
· | by deflecting an electron beam in a discharge tube (Fulltext... Hierarchy... Expanded...H03D 1/26 takes precedence)

P:40 |  | H03D 3/00 |
Demodulation of angle-modulated oscillations (Fulltext... Hierarchy... Expanded...H03D 5/00, Fulltext... Hierarchy... Expanded...H03D 9/00, Fulltext... Hierarchy... Expanded...H03D 11/00 take precedence)

|  | H03D 3/02 |
· | by detecting phase difference between two signals obtained from input signal (Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...H03D 3/28-H03D 3/32 take precedence; limiting arrangements Fulltext... Hierarchy... Expanded...H03G 11/00)

|  | H03D 3/04 |
· · | by counting or integrating cycles of oscillations

|  | H03D 3/06 |
· · | by combining signals additively or in product demodulators

|  | H03D 3/08 |
· · · | by means of diodes, e.g. Foster-Seeley discriminator

|  | H03D 3/10 |
· · · · | in which the diodes are simultaneously conducting during the same half period of the signal, e.g. ratio detector

|  | H03D 3/12 |
· · · | by means of discharge tubes having more than two electrodes

|  | H03D 3/14 |
· · · | by means of semiconductor devices having more than two electrodes

|  | H03D 3/16 |
· · · | by means of electromechanical resonators

|  | H03D 3/18 |
· · | by means of synchronous gating arrangements

|  | H03D 3/20 |
· · · | producing pulses whose amplitude or duration depends on the phase difference

|  | H03D 3/22 |
· · | by means of active elements with more than two electrodes to which two signals are applied derived from the signal to be demodulated and having a phase difference related to the frequency deviation, e.g. phase detector

|  | H03D 3/24 |
· · | Modifications of demodulators to reject or remove amplitude variations by means of locked-in oscillator circuits

|  | H03D 3/26 |
· | by means of sloping amplitude/frequency characteristic of tuned or reactive circuit (Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...H03D 3/28-H03D 3/32 take precedence)

|  | H03D 3/28 |
· | Modifications of demodulators to reduce effect of temperature variations (automatic frequency control Fulltext... Hierarchy... Expanded...H03L)

|  | H03D 3/30 |
· | by means of transit-time tubes

|  | H03D 3/32 |
· | by deflecting an electron beam in a discharge tube (Fulltext... Hierarchy... Expanded...H03D 3/30 takes precedence)

|  | H03D 3/34 |
· | by means of electromechanical devices (Fulltext... Hierarchy... Expanded...H03D 3/16 takes precedence) [3]

P:30 |  | H03D 5/00 |
Circuits for demodulating amplitude-modulated or angle-modulated oscillations at will (Fulltext... Hierarchy... Expanded...H03D 9/00, Fulltext... Hierarchy... Expanded...H03D 11/00 take precedence)

P:20 |  | H03D 7/00 |
Transference of modulation from one carrier to another, e.g. frequency-changing (Fulltext... Hierarchy... Expanded...H03D 9/00, Fulltext... Hierarchy... Expanded...H03D 11/00 take precedence; dielectric amplifiers, magnetic amplifiers, parametric amplifiers used as frequency-changers Fulltext... Hierarchy... Expanded...H03F)

|  | H03D 7/02 |
· | by means of diodes (Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...H03D 7/14-H03D 7/22 take precedence)

|  | H03D 7/04 |
· · | having negative resistance characteristic, e.g. tunnel diode

|  | H03D 7/06 |
· | by means of discharge tubes having more than two electrodes (Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...H03D 7/14-H03D 7/22 take precedence)

|  | H03D 7/08 |
· · | the signals to be mixed being applied between the same two electrodes

|  | H03D 7/10 |
· · | the signals to be mixed being applied between different pairs of electrodes

|  | H03D 7/12 |
· | by means of semiconductor devices having more than two electrodes (Fulltext... Hierarchy... Expanded...Fulltext... Hierarchy... Expanded...H03D 7/14-H03D 7/22 take precedence)

|  | H03D 7/14 |
· | Balanced arrangements

|  | H03D 7/16 |
· | Multiple frequency-changing

|  | H03D 7/18 |
· | Modifications of frequency-changers for eliminating image frequencies

|  | H03D 7/20 |
· | by means of transit-time tubes

|  | H03D 7/22 |
· | by deflecting an electron beam in a discharge tube (Fulltext... Hierarchy... Expanded...H03D 7/20 takes precedence)

P:10 |  | H03D 9/00 |
Demodulation or transference of modulation of modulated electromagnetic waves (devices or arrangements for demodulating light, transferring modulation in light waves Fulltext... Hierarchy... Expanded...G02F 2/00)

|  | H03D 9/02 |
· | Demodulation using distributed inductance and capacitance, e.g. in feeder lines

|  | H03D 9/04 |
· · | for angle-modulated oscillations

|  | H03D 9/06 |
· | Transference of modulation using distributed inductance and capacitance

P:0 |  | H03D 11/00 |
Super-regenerative demodulator circuits

|  | H03D 11/02 |
· | for amplitude-modulated oscillations

|  | H03D 11/04 |
· · | by means of semiconductor devices having more than two electrodes

|  | H03D 11/06 |
· | for angle-modulated oscillations

|  | H03D 11/08 |
· · | by means of semiconductor devices having more than two electrodes

P:60 |  | H03D 13/00 |
Circuits for comparing the phase or frequency of two mutually-independent oscillations

P:70 |  | H03D 99/00 |
Subject matter not provided for in other groups of this subclass [8]