H
SECTION H — ELECTRICITY
 H03
BASIC ELECTRONIC CIRCUITRY
 H03G
CONTROL OF AMPLIFICATION (impedance networks, e.g. attenuators, H03H; control of transmission in lines H04B 3/04)
 H03G

Note(s)

  1. 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.
  2. Attention is drawn to the note following the title of sub-class 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 G05, G08; combined with remote tuning or selection of resonant circuits 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 H03F 1/08)
 H03G 3/00
Gain control in amplifiers or frequency changers (gated amplifiers H03F 3/72; peculiar to television receivers 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 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 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 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 H03G 3/00; tone control and bandwidth control 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 (H03G 11/04, H03G 11/06, 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 H03D 3/00)
 H03G 11/08
·  Limiting rate of change of amplitude