|  | H |
SECTION H — ELECTRICITY

|  | H04 |
ELECTRIC COMMUNICATION TECHNIQUE

|  | H04J |
MULTIPLEX COMMUNICATION (transmission in general Fulltext... Hierarchy... Expanded...H04B; peculiar to telegraphic communication Fulltext... Hierarchy... Expanded...H04L 5/00; systems for transmitting television signals simultaneously or sequentially Fulltext... Hierarchy... Expanded...H04N 7/08; in exchanges Fulltext... Hierarchy... Expanded...H04Q 11/00)

|  | H04J |
Note(s) This sub-class deals with (a) circuits or apparatus for combining or dividing signals for the purpose of transmitting them simultaneously or sequentially over the same transmission path, and (b) monitoring arrangements therefor.

|  | H04J 1/00 |
Frequency-division multiplex systems

|  | H04J 1/02 |
· | Details

|  | H04J 1/04 |
· · | Frequency-transposition arrangements

|  | H04J 1/06 |
· · | Arrangements for supplying the carrier waves

|  | H04J 1/08 |
· · | Arrangements for combining channels

|  | H04J 1/10 |
· · | Intermediate station arrangements, e.g. for branching, for tapping-off

|  | H04J 1/12 |
· · | Arrangements for reducing cross-talk between channels

|  | H04J 1/14 |
· · | Arrangements providing for calling or supervisory signals

|  | H04J 1/16 |
· · | Monitoring arrangements

|  | H04J 1/18 |
· | Systems in which all the carriers are amplitude-modulated

|  | H04J 1/20 |
· | Systems in which at least one carrier is angle-modulated

|  | H04J 3/00 |
Time-division multiplex systems

|  | H04J 3/02 |
· | Details

|  | H04J 3/04 |
· · | Distributors combined with modulators or demodulators (distributors in general Fulltext... Hierarchy... Expanded...H03K 19/40)

|  | H04J 3/06 |
· · | Synchronising arrangements

|  | H04J 3/08 |
· · | Intermediate station arrangements, e.g. for branching, for tapping-off

|  | H04J 3/10 |
· · | Arrangements for reducing cross-talk between channels

|  | H04J 3/12 |
· · | Arrangements providing for calling or supervisory signals

|  | H04J 3/14 |
· · | Monitoring arrangements

|  | H04J 3/16 |
· | Systems in which the time allocation to individual channels within a transmission cycle is variable, e.g. to accommodate varying complexity of signals, to vary number of channels transmitted (Fulltext... Hierarchy... Expanded...H04J 5/00 takes precedence)

|  | H04J 3/18 |
· | Systems using frequency compression and subsequent expansion of the individual signals

|  | H04J 5/00 |
Multiplex systems in which a transmission channel allotted to a first user may be taken away and re-allotted to a second user if the first user becomes inactive, e.g. TASI

|  | H04J 7/00 |
Multiplex systems in which the amplitudes or durations of the signals in individual channels are characteristic of those channels

|  | H04J 7/02 |
· | in which the polarity of the amplitude is characteristic

|  | H04J 9/00 |
Multiplex systems in which each channel is represented by a different type of modulation of the carrier