GB1430982A - Amplifier for use in communication systems - Google Patents

Amplifier for use in communication systems

Info

Publication number
GB1430982A
GB1430982A GB2296573A GB2296573A GB1430982A GB 1430982 A GB1430982 A GB 1430982A GB 2296573 A GB2296573 A GB 2296573A GB 2296573 A GB2296573 A GB 2296573A GB 1430982 A GB1430982 A GB 1430982A
Authority
GB
United Kingdom
Prior art keywords
output
transistor
amplifier
signal
polarity
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
GB2296573A
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.)
Plantronics Inc
Original Assignee
Plantronics Inc
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 Plantronics Inc filed Critical Plantronics Inc
Priority claimed from US415318A external-priority patent/US3900340A/en
Publication of GB1430982A publication Critical patent/GB1430982A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M6/00—Primary cells; Manufacture thereof
    • H01M6/04—Cells with aqueous electrolyte
    • H01M6/06—Dry cells, i.e. cells wherein the electrolyte is rendered non-fluid
    • H01M6/10—Dry cells, i.e. cells wherein the electrolyte is rendered non-fluid with wound or folded electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/24—Alkaline accumulators
    • H01M10/28—Construction or manufacture
    • H01M10/286—Cells or batteries with wound or folded electrodes
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/60—Substation equipment, e.g. for use by subscribers including speech amplifiers
    • H04M1/6008—Substation equipment, e.g. for use by subscribers including speech amplifiers in the transmitter circuit
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Abstract

1430982 Transistor amplifying circuits PLANTRONICS Inc 15 May 1973 [17 May 1972] 22965/73 Headings H4K H4R and H3T In an amplifier which is supplied with power over the signal output lines the signal is applied to the output amplifiers 18, 19, via signal processing means 12, 13, 14, which is supplied with power via a current steering network 17 which provides a constant polarity voltage to the processing means irrespective of the polarity of the supply on terminals 21, 22 and the output amplifiers 18, 19, are such that with one polarity of supply one amplifier is effective and with the other polarity of supply the other amplifier is effective. As described the current steering network comprises transistors 83, 84, 87, 88 connected in a bridge network with either the pair 83, 87, or the pair 84, 88, turned on by the respective power supply polarity which causes conduction through the emitter base junctions of the respective pair and the common resistor 86. Alternative current steering networks, using independent base circuit resistors, are described with respect to Figs. 6, 7, 8. The signal processing means comprises a variable attenuator circuit including resistors 44, 45, 48 and the emitter collector path of transistor 46 whose base is connected to a control circuit including transistor 109 which is turned on to provide the high attenuation condition or off to provide low attenuation of the attenuator, with a capacitor 107 on the base of transistor 109 to provide a "hold over" time constant. Conduction of transistor 109 is controlled by the differential amplifier circuit which is unbalanced at low preamplifier signal levels and gives the low gain condition, and is balanced when the signal exceeds a predetermined level to provide the high gain condition. Transistor 76 transfers the signal from the output of emitter follower 52 to the output amplifiers 95, 96, 97, 99 and the gain of transistor 76 is controlled by the output current to give a high gain at high output currents and a lower gain at lower output currents to provide, at the output terminals, a signal level characteristic with respect to line current which is similar to that provided by a carbon microphone. Selection of which output amplifier is enabled is provided by the rectifiers 93 and 94 in the output amplifier circuits.
GB2296573A 1972-05-17 1973-05-15 Amplifier for use in communication systems Expired GB1430982A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US25405972A 1972-05-17 1972-05-17
US415318A US3900340A (en) 1973-11-13 1973-11-13 Galvanic cell structures employing coiled electrodes

Publications (1)

Publication Number Publication Date
GB1430982A true GB1430982A (en) 1976-04-07

Family

ID=26943797

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2296573A Expired GB1430982A (en) 1972-05-17 1973-05-15 Amplifier for use in communication systems

Country Status (1)

Country Link
GB (1) GB1430982A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4993060A (en) * 1988-02-23 1991-02-12 Kelly Gavan E Portable device for use by a news reporter

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4993060A (en) * 1988-02-23 1991-02-12 Kelly Gavan E Portable device for use by a news reporter

Similar Documents

Publication Publication Date Title
SE8008239L (en) DEVICE FOR CONTROLING A PHONE LINE FEED POWER
GB1178348A (en) Negative Feedback Circuit Employing Combination Amplifier and Lead-Lag Compensation Network.
GB1364233A (en) High performance solid state amplifier
US4002852A (en) Electronic telephone network
GB1018834A (en) Amplifier
GB1274449A (en) Sorting apparatus and a method of sorting
GB1446068A (en) Stabilization of quiescent collector potential of current-mode biased transistors-
GB1242312A (en) Improvements in or relating to telephone speech circuits
GB1430982A (en) Amplifier for use in communication systems
GB1469990A (en) Gain control circuit
GB1462395A (en) Boot-strapped amplifier
GB1325784A (en) Telephone circuits utilizing active elements
GB952904A (en) Improvements in or relating to amplifiers
US4560834A (en) Current limiter circuit for battery feed in a telephone circuit
GB1487762A (en) Automatic volume control system
ES373031A1 (en) Variable loss device
KR900019348A (en) Electronic circuit
GB1377157A (en) Gain control circuit
GB1130060A (en) Improvements in and relating to electric amplifiers
GB1223053A (en) Improvements in or relating to balanced to unbalanced coupling circuits
GB1338487A (en) Transistor amplifier
GB1290869A (en)
SU409350A1 (en) ELEMENT OF AUTOMATIC GAIN ADJUSTMENT
GB1030941A (en) Circuit arrangement for varying the level of a signal
GB1294108A (en) Use of an electronic circuit forming a non-linear and variable impedance

Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
PE20 Patent expired after termination of 20 years

Effective date: 19930514