ES345668A1 - Recording and/or Playback Apparatus - Google Patents

Recording and/or Playback Apparatus

Info

Publication number
ES345668A1
ES345668A1 ES345668A ES345668A ES345668A1 ES 345668 A1 ES345668 A1 ES 345668A1 ES 345668 A ES345668 A ES 345668A ES 345668 A ES345668 A ES 345668A ES 345668 A1 ES345668 A1 ES 345668A1
Authority
ES
Spain
Prior art keywords
filter
recording
lamp
signal level
amplifier
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
ES345668A
Other languages
Spanish (es)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Koninklijke Philips NV
Original Assignee
Philips Gloeilampenfabrieken NV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Philips Gloeilampenfabrieken NV filed Critical Philips Gloeilampenfabrieken NV
Publication of ES345668A1 publication Critical patent/ES345668A1/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03G—CONTROL OF AMPLIFICATION
    • H03G1/00—Details of arrangements for controlling amplification
    • H03G1/0005—Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal
    • H03G1/0035—Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal using continuously variable impedance elements
    • H03G1/0047—Circuits characterised by the type of controlling devices operated by a controlling current or voltage signal using continuously variable impedance elements using photo-electric elements
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B23/00—Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus ; Intermediate mediums; Apparatus or processes specially adapted for their manufacture
    • G11B23/0007—Circuits or methods for reducing noise, for correction of distortion, or for changing density of recorded information
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03G—CONTROL OF AMPLIFICATION
    • H03G5/00—Tone control or bandwidth control in amplifiers
    • H03G5/16—Automatic control
    • H03G5/18—Automatic control in untuned amplifiers
    • H03G5/22—Automatic control in untuned amplifiers having semiconductor devices
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H11/00—Networks using active elements
    • H03H11/02—Multiple-port networks
    • H03H11/04—Frequency selective two-port networks
    • H03H11/0405—Non-linear filters

Landscapes

  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • Networks Using Active Elements (AREA)

Abstract

A recording and/or playback amplifier Fig. 4 includes a low pass filter 12 having a circuit element, e.g. lamp 18, whose impedance depends on signal level so that the cut off frequency of the filter is reduced as the signal level reduces, to reduce the disturbing effects of high frequency noise components. The filter may alternatively be formed by a series negative temperature coefficient resistor and a shunt capacitor. As shown the lamp 18 is also used to provide automatic gain control by varying the resistance of the photo sensitive resistor 20 in the negative feedback path 19 of the amplifier.
ES345668A 1966-10-04 1967-10-02 Recording and/or Playback Apparatus Expired ES345668A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEN0029282 1966-10-04

Publications (1)

Publication Number Publication Date
ES345668A1 true ES345668A1 (en) 1968-11-16

Family

ID=7345030

Family Applications (1)

Application Number Title Priority Date Filing Date
ES345668A Expired ES345668A1 (en) 1966-10-04 1967-10-02 Recording and/or Playback Apparatus

Country Status (7)

Country Link
BE (1) BE704624A (en)
CH (1) CH464558A (en)
DE (1) DE1499809A1 (en)
ES (1) ES345668A1 (en)
GB (1) GB1196647A (en)
NL (1) NL6713244A (en)
SE (1) SE328712B (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3798559A (en) * 1971-04-20 1974-03-19 Matsushita Electric Ind Co Ltd Noise reduction system

Also Published As

Publication number Publication date
BE704624A (en) 1968-04-03
CH464558A (en) 1968-10-31
DE1499809A1 (en) 1970-02-19
GB1196647A (en) 1970-07-01
NL6713244A (en) 1968-04-05
SE328712B (en) 1970-09-21

Similar Documents

Publication Publication Date Title
GB1290164A (en)
GB889855A (en) Circuit arrangement for stabilizing the output of a vidicon pickup tube
ES345668A1 (en) Recording and/or Playback Apparatus
GB1268789A (en) Constant output oscillator
GB1216298A (en) Audio level clipper and compressor
JPS57120207A (en) Reproducing device for multiple-recorded information
GB1161002A (en) Improvements in and relating to Hearing Aids
GB773470A (en) Improvements in or relating to detector-circuit arrangements
GB1030941A (en) Circuit arrangement for varying the level of a signal
ATE50672T1 (en) CIRCUIT ARRANGEMENT FOR VOLUME ADJUSTMENT.
GB1446217A (en) Gain control circuit
GB1098519A (en) Improvements in or relating to audio circuit arrangements
US4101843A (en) Automatic recording level control circuit with manual sensitivity compensating circuit
SU370706A1 (en) FOSTER 11L? NTNO-.Lp ^^ 1E ~ W
JPS56109012A (en) Automatic gain control circuit
GB1115015A (en) Improvements in or relating to automatic bandwidth adjustment of an audio frequency signal
FR2331912A1 (en) Active bandpass filter of second order - with independently controlled parameters for modulated telephone signals
GB1252633A (en)
JPS5931045Y2 (en) feedback amplifier circuit
JPS5650608A (en) Filter device
JPS56111375A (en) Picture signal amplifying circuit
GB1182490A (en) Variable Attenuators
SE332017B (en)
DE3169247D1 (en) Active tone control circuit of a transistor hearing apparatus amplifier with two or more stages
ATE27668T1 (en) FREQUENCY SELECTIVE CONTROLLED ELECTRONIC AMPLIFIER CIRCUIT.