|  | H |
SECTION H — ELECTRICITY

|  | H03 |
BASIC ELECTRONIC CIRCUITRY

|  | H03G |
CONTROL OF AMPLIFICATION (impedance networks, e.g. attenuators, Fulltext... Hierarchy... Expanded...H03H; control of transmission in lines Fulltext... Hierarchy... Expanded...H04B 3/04)

|  | H03G |
Note(s) This sub-class deals with (a) control of gain of amplifiers or frequency-changers, (b) control of frequency range of amplifiers, and (c) limiting amplitude or rate of change of amplitude. Attention is drawn to the note following the title of sub-class Fulltext... Hierarchy... Expanded...H03F. [3]

|  | H03G 1/00 |
Details of arrangements for controlling amplification

|  | H03G 1/02 |
· | Remote control of amplification, tone, or bandwidth (remote control in general Fulltext... Hierarchy... Expanded...G05, Fulltext... Hierarchy... Expanded...G08; combined with remote tuning or selection of resonant circuits Fulltext... Hierarchy... Expanded...H03J)

|  | H03G 1/04 |
· | Modifications of control circuit to reduce distortion caused by control (modifications to reduce influence of variations of internal impedance of amplifying elements caused by control Fulltext... Hierarchy... Expanded...H03F 1/08)

|  | H03G 3/00 |
Gain control in amplifiers or frequency changers (gated amplifiers Fulltext... Hierarchy... Expanded...H03F 3/72; peculiar to television receivers Fulltext... Hierarchy... Expanded...H04N)

|  | H03G 3/02 |
· | Manually-operated control

|  | H03G 3/04 |
· · | in untuned amplifiers

|  | H03G 3/06 |
· · · | having discharge tubes

|  | H03G 3/08 |
· · · · | incorporating negative feedback

|  | H03G 3/10 |
· · · | having semiconductor devices

|  | H03G 3/12 |
· · · · | incorporating negative feedback

|  | H03G 3/14 |
· · | in frequency-selective amplifiers

|  | H03G 3/16 |
· · · | having discharge tubes

|  | H03G 3/18 |
· · · | having semiconductor devices

|  | H03G 3/20 |
· | Automatic control (combined with volume compression or expansion Fulltext... Hierarchy... Expanded...H03G 7/00)

|  | H03G 3/22 |
· · | in amplifiers having discharge tubes

|  | H03G 3/24 |
· · · | Control dependent upon ambient noise level or sound level

|  | H03G 3/26 |
· · · | Muting amplifier when no signal is present

|  | H03G 3/28 |
· · · · | in frequency-modulation receivers

|  | H03G 3/30 |
· · | in amplifiers having semiconductor devices

|  | H03G 3/32 |
· · · | the control being dependent upon ambient noise level or sound level

|  | H03G 3/34 |
· · · | Muting amplifier when no signal is present

|  | H03G 5/00 |
Tone control or bandwidth control in amplifiers

|  | H03G 5/02 |
· | Manually-operated control (variable bandpass or bandstop filters Fulltext... Hierarchy... Expanded...H03H 7/12)

|  | H03G 5/04 |
· · | in untuned amplifiers

|  | H03G 5/06 |
· · · | having discharge tubes

|  | H03G 5/08 |
· · · · | incorporating negative feedback

|  | H03G 5/10 |
· · · | having semiconductor devices

|  | H03G 5/12 |
· · · · | incorporating negative feedback

|  | H03G 5/14 |
· · | in frequency-selective amplifiers

|  | H03G 5/16 |
· | Automatic control

|  | H03G 5/18 |
· · | in untuned amplifiers

|  | H03G 5/20 |
· · · | having discharge tubes

|  | H03G 5/22 |
· · · | having semiconductor devices

|  | H03G 5/24 |
· · | in frequency-selective amplifiers

|  | H03G 5/26 |
· · · | having discharge tubes

|  | H03G 5/28 |
· · · | having semiconductor devices

|  | H03G 7/00 |
Volume compression or expansion in amplifiers

|  | H03G 7/02 |
· | having discharge tubes

|  | H03G 7/04 |
· · | incorporating negative feedback

|  | H03G 7/06 |
· | having semiconductor devices

|  | H03G 7/08 |
· · | incorporating negative feedback

|  | H03G 9/00 |
Combinations of two or more types of control, e.g. gain control and tone control

|  | H03G 9/02 |
· | in untuned amplifiers (combined tone controls for low and high frequencies Fulltext... Hierarchy... Expanded...H03G 5/00)

|  | H03G 9/04 |
· · | having discharge tubes

|  | H03G 9/06 |
· · · | for gain control and tone control

|  | H03G 9/08 |
· · · · | incorporating negative feedback

|  | H03G 9/10 |
· · · | for tone control and volume expansion or compression

|  | H03G 9/12 |
· · | having semiconductor devices

|  | H03G 9/14 |
· · · | for gain control and tone control

|  | H03G 9/16 |
· · · · | incorporating negative feedback

|  | H03G 9/18 |
· · · | for tone control and volume expansion or compression

|  | H03G 9/20 |
· | in frequency-selective amplifiers

|  | H03G 9/22 |
· · | having discharge tubes

|  | H03G 9/24 |
· · | having semiconductor devices

|  | H03G 9/26 |
· | in untuned amplifying stages as well as in frequency-selective amplifying stages (gain control in both stages Fulltext... Hierarchy... Expanded...H03G 3/00; tone control and bandwidth control Fulltext... Hierarchy... Expanded...H03G 5/00)

|  | H03G 9/28 |
· · | all amplifying stages having discharge tubes

|  | H03G 9/30 |
· · | all amplifying stages having semiconductor devices

|  | H03G 11/00 |
Limiting amplitude; Limiting rate of change of amplitude

|  | H03G 11/02 |
· | by means of diodes (Fulltext... Hierarchy... Expanded...H03G 11/04, Fulltext... Hierarchy... Expanded...H03G 11/06, Fulltext... Hierarchy... Expanded...H03G 11/08 take precedence)

|  | H03G 11/04 |
· | Limiting level dependent on strength of signal; Limiting level dependent on strength of carrier on which signal is modulated

|  | H03G 11/06 |
· | Limiters of angle-modulated signals; such limiters combined with discriminators (discriminators having an inherent limiting action Fulltext... Hierarchy... Expanded...H03D 3/00)

|  | H03G 11/08 |
· | Limiting rate of change of amplitude