H
SECTION H — ELECTRICITY
 H04
ELECTRIC COMMUNICATION TECHNIQUE
 H04Q
SELECTING (switches, relays, selectors H01H; electronic switches H03K 17/00)
 H04Q

Note(s)

  1. This sub-class deals with methods, circuits, or apparatus for establishing selectively a connection between a desired number of stations (normally two), or between a main station and a desired number of substations (normally one) for the purpose of transferring information via this connection after it has been established. The sub-class also deals with selective calling arrangements over connections already established. In either case, the connection may be by means of electric conductors or electromagnetic waves.
  2. In this sub-class:
    1. "Subscriber" is a general term for terminal equipment, e.g. telephone for public use.
    2. "Substation" means a subscriber or monitoring equipment which may connect a single subscriber to a line without choice as to subscriber.
    3. A "satellite" is a kind of exchange the operation of which depends upon control signals received from a supervisory exchange.
    4. "Switching centres" include exchanges and satellites.
 H04Q 1/00
Details of selecting apparatus or arrangements (details of selector switches H01H 63/00)
 H04Q 1/02
·  Constructional details
 H04Q 1/04
·  ·  Frames or mounting racks for selector switches; Accessories therefor, e.g. frame cover
 H04Q 1/06
·  ·  Cable ducts or mountings specially adapted for exchange installations (in general H02G)
 H04Q 1/08
·  ·  Frames or mounting racks for relays; Accessories therefor
 H04Q 1/10
·  ·  Exchange station construction
 H04Q 1/12
·  ·  Arrangements of multiple bars with or without pivotable frames
 H04Q 1/14
·  ·  Distribution frames
 H04Q 1/16
·  ·  Wiring arrangements for selector switches or relays in frames
 H04Q 1/18
·  Electrical details
 H04Q 1/20
·  ·  Testing circuits or apparatus; Circuits or apparatus for detecting, indicating, or signalling faults or troubles
 H04Q 1/22
·  ·  ·  Automatic arrangements
 H04Q 1/24
·  ·  ·  ·  for connection devices
 H04Q 1/26
·  ·  ·  ·  for signalling trouble in unoccupied sub-exchanges
 H04Q 1/28
·  ·  Current-supply circuits or arrangements for selection equipment at exchanges
 H04Q 1/30
·  ·  Signalling arrangements; Manipulation of signalling currents (multiplex systems providing for calling or supervisory signals H04J 1/14, H04J 3/12; telephone substation equipment H04M 1/00)
 H04Q 1/32
·  ·  ·  using trains of dc pulses (H04Q 1/39 takes precedence)
 H04Q 1/34
·  ·  ·  ·  Impulse regenerators with mechanical or other non-electrical marking arrangements
 H04Q 1/36
·  ·  ·  ·  Pulse-correcting arrangements, e.g. for reducing effects due to interference
 H04Q 1/38
·  ·  ·  using combinations of direct currents of different amplitudes or polarities over line conductors or combination of line conductors
 H04Q 1/39
·  ·  ·  using coded pulse groups  [3]
 H04Q 1/40
·  ·  ·  whereby duration of pulse or interval between two pulses is variable
 H04Q 1/42
·  ·  ·  ·  involving the position of a pulse in a cycle
 H04Q 1/44
·  ·  ·  using ac (H04Q 1/50 takes precedence)
 H04Q 1/442
·  ·  ·  ·  with out-of-voice band signalling frequencies  [3]
 H04Q 1/444
·  ·  ·  ·  with voice-band signalling frequencies  [3]
 H04Q 1/446
·  ·  ·  ·  ·  using one signalling frequency (H04Q 1/46 take precedence)  [3]
 H04Q 1/448
·  ·  ·  ·  ·  ·  with conversion of a single frequency signal into a digital signal)  [3]
 H04Q 1/45
·  ·  ·  ·  ·  using multi-frequency signalling (H04Q 1/46 takes precedence)
 H04Q 1/453
·  ·  ·  ·  ·  ·  in which m-out-of-n signalling frequencies are transmitted  [3]
 H04Q 1/457
·  ·  ·  ·  ·  ·  with conversion of multifrequency signals into digital signals  [3]
 H04Q 1/46
·  ·  ·  ·  ·  comprising means for distinguishing between a signalling current of predetermined frequency and a complex current containing that frequency, e.g. speech current
 H04Q 1/48
·  ·  ·  Induced-current signalling arrangements
 H04Q 1/50
·  ·  ·  Conversion between different kinds of signals
 H04Q 1/52
( covered by H04Q 3/52 )
 H04Q 1/54
·  ·  Amplifier switched-on automatically in dependence on automatically selected lines
 H04Q 1/56
·  ·  Balancing circuitry switched-on automatically in dependence on automatically selected lines
 H04Q 3/00
Selecting arrangements (H04Q 5/00, H04Q 7/00, H04Q 9/00, H04Q 11/00 take precedence)
 H04Q 3/02
·  Circuit arrangements for selectors responsive to a permutation code
 H04Q 3/04
·  Circuit arrangements for receivers of routing digits
 H04Q 3/06
·  ·  for group or trunk group selectors
 H04Q 3/08
·  ·  for local or long-distance selectors
 H04Q 3/10
·  ·  for PBX selectors, i.e. private branche exchange selectors
 H04Q 3/12
·  ·  for line selectors providing transfer of routing digits
 H04Q 3/14
·  ·  for two-way operation selectors
 H04Q 3/16
·  ·  for marking-switches
 H04Q 3/18
·  Circuit arrangements for first stage of hunting switching
 H04Q 3/20
·  ·  for preselectors
 H04Q 3/22
·  ·  ·  comprising common calling and disconnecting circuit
 H04Q 3/24
·  ·  for line finders
 H04Q 3/26
·  ·  ·  comprising common calling and disconnecting circuit
 H04Q 3/28
·  ·  ·  comprising main groups and sub-groups
 H04Q 3/30
·  ·  Selector finders, i.e. allotters
 H04Q 3/32
·  Circuit arrangements for second or subsequent stages of hunting switching  [2]
 H04Q 3/34
·  ·  for the second preselection stage
 H04Q 3/36
·  ·  for the second line-finder stage
 H04Q 3/38
·  ·  for stages after the group-selector stage
 H04Q 3/40
·  ·  for stages after the line selector, e.g. for extension selector
 H04Q 3/42
·  Circuit arrangements for indirect selecting controlled by common circuits, e.g. register controller marker
 H04Q 3/44
·  ·  using revertive control
 H04Q 3/46
·  ·  using signals other than revertive impulses
 H04Q 3/47
·  ·  using translators
 H04Q 3/48
·  ·  using markers
 H04Q 3/49
·  ·  ·  for end-to-end marking
 H04Q 3/495
·  ·  ·  for routing connecting paths
 H04Q 3/52
·  ·  using static devices in switching stages, e.g. electronic switching arrangements  [2]
 H04Q 3/54
·  ·  in which the logic circuitry controlling the exchange is centralised, e.g. using a stored programme
 H04Q 3/56
·  ·  in which the control signals are multiplexed  [2]
 H04Q 3/58
·  Arrangements providing connection between main exchange and sub-exchange or satellite
 H04Q 3/60
·  ·  for connecting to satellites or concentrators which connect one or more exchange lines with a group of local lines
 H04Q 3/62
·  ·  for connecting to private branch exchanges
 H04Q 3/64
·  Distributing or queueing
 H04Q 3/66
·  ·  Traffic distributors
 H04Q 3/68
·  ·  Grouping or interlacing selector groups or stages
 H04Q 3/70
·  Identification of class of calling subscriber
 H04Q 3/72
·  Finding out and indicating number of calling subscriber
 H04Q 3/74
·  ·  Identification of subscriber calling from a party-line
 H04Q 5/00
Selecting arrangements wherein two or more subscriber stations are connected by the same line to the exchange
 H04Q 5/02
·  with direct connection for all subscribers, i.e. party-line system (H04Q 5/24 takes precedence)
 H04Q 5/04
·  ·  Signalling by currents in one or other or both line wires or additional wires
 H04Q 5/06
·  ·  Signalling by amplitude or polarity of dc
 H04Q 5/08
·  ·  Signalling by continuous ac
 H04Q 5/10
·  ·  ·  using single frequencies for different subscribers
 H04Q 5/12
·  ·  ·  using combinations of frequencies
 H04Q 5/14
·  ·  Signalling by pulses
 H04Q 5/16
·  ·  ·  by predetermined number of pulses
 H04Q 5/18
·  with indirect connection, i.e. through subordinate switching centre
 H04Q 5/20
·  ·  the subordinate centre permitting interconnection of subscribers connected thereto
 H04Q 5/22
·  ·  the subordinate centre not permitting interconnection of subscribers connected thereto
 H04Q 5/24
·  for two-party-line systems
 H04Q 7/00
Selecting arrangements to which subscribers are connected via radio links or inductive links
 H04Q 7/02
·  for subscribers using radio or inductive link only
 H04Q 7/04
·  with possibility of connection to and from line exchanges
 H04Q 9/00
Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom
 H04Q 9/02
·  Automatically-operated arrangements
 H04Q 9/04
·  Arrangements for synchronous operation
 H04Q 9/06
·  Calling by using amplitude or polarity of dc
 H04Q 9/08
·  Calling by using continuous ac
 H04Q 9/10
·  ·  using single different frequencies
 H04Q 9/12
·  ·  using combinations of frequencies
 H04Q 9/14
·  Calling by using pulses
 H04Q 9/16
·  ·  by predetermined number of pulses
 H04Q 11/00
Selecting arrangements for multiplex systems (multiplex systems H04J)
 H04Q 11/02
·  for frequency-division multiplexing
 H04Q 11/04
·  for time-division multiplexing