GB366920A - Improvements in or relating to thermionic amplifying devices - Google Patents

Improvements in or relating to thermionic amplifying devices

Info

Publication number
GB366920A
GB366920A GB3337030A GB3337030A GB366920A GB 366920 A GB366920 A GB 366920A GB 3337030 A GB3337030 A GB 3337030A GB 3337030 A GB3337030 A GB 3337030A GB 366920 A GB366920 A GB 366920A
Authority
GB
United Kingdom
Prior art keywords
current
resistances
input
diagonal
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
GB3337030A
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.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
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 Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to GB3337030A priority Critical patent/GB366920A/en
Priority to FR725422D priority patent/FR725422A/en
Priority to DEI42981D priority patent/DE613855C/en
Publication of GB366920A publication Critical patent/GB366920A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/02—Details
    • H04B3/04—Control of transmission; Equalising
    • H04B3/10—Control of transmission; Equalising by pilot signal

Abstract

366,920. Valve amplifying circuits. STANDARD TELEPHONES & CABLES, Ltd. and TERRY, V. J., Columbia House, Aldwych, London. Nov. 6, 1930, No. 33370. [Class 40 (v).] Automatic gain control is provided by arranging the input to an amplifier as an unbalanced bridge and utilizing a control current to vary the balance by increasing and decreasing the impedances in two of the arms. Fig. 1 shows a multi-channel carrier telegraph receiver in which the input contains resistances 3, 4, which may be a carbon filament and a metal filament lamps respectively, the heating of the lamps is determined by a control current through the circuit 10. A neon discharge tube 15 coupled to the output acts as a safety device if high transients are produced or if either resistance fails. Alternatively a grid-leak condenser combination in the amplifier or a current limiter may be used. The resistances 3, 4 may be arranged in the form of a Wheatstone bridge as shown in Fig. 4 with the input applied to one diagonal and the output taken from the other diagonal. Alternatively three winding transformers may be used in the input as shown in Fig. 3 and the resistances 3, 4 may be either directly heated by rectified and smoothed current or indirectly heated by unrectified current. The control current may be derived from the signal or a separate pilot current may be sent and may operate a relay in the circuit of a local source of heating current. Since transmission variation is not equal at all frequencies impedances variable with frequency may be used in series or in parallel with the resistances 3, 4 to provide compensation.
GB3337030A 1930-11-06 1930-11-06 Improvements in or relating to thermionic amplifying devices Expired GB366920A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
GB3337030A GB366920A (en) 1930-11-06 1930-11-06 Improvements in or relating to thermionic amplifying devices
FR725422D FR725422A (en) 1930-11-06 1931-10-29 Improvements to electrical amplifying devices of the thermionic type
DEI42981D DE613855C (en) 1930-11-06 1931-11-07 Device for automatically keeping the level constant in transmission systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB3337030A GB366920A (en) 1930-11-06 1930-11-06 Improvements in or relating to thermionic amplifying devices

Publications (1)

Publication Number Publication Date
GB366920A true GB366920A (en) 1932-02-08

Family

ID=10352042

Family Applications (1)

Application Number Title Priority Date Filing Date
GB3337030A Expired GB366920A (en) 1930-11-06 1930-11-06 Improvements in or relating to thermionic amplifying devices

Country Status (3)

Country Link
DE (1) DE613855C (en)
FR (1) FR725422A (en)
GB (1) GB366920A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2625606A (en) * 1947-11-25 1953-01-13 Bell Telephone Labor Inc Thermistor control circuit
US2680193A (en) * 1950-06-17 1954-06-01 Bendix Aviat Corp Data smoother
US2714635A (en) * 1944-08-07 1955-08-02 Otto H Schmitt Modulator-thermal demodulator system
US2754418A (en) * 1949-04-28 1956-07-10 Bendix Aviat Corp Control circuit for a servo system
US3159796A (en) * 1961-07-10 1964-12-01 Gen Dynamics Corp Direct current controlled bridge type attenuator

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE757106C (en) * 1937-04-01 1953-02-23 Siemens & Halske A G Radiation-cooled heat conductor for regulating very small powers
DE743025C (en) * 1941-04-01 1943-12-17 Siemens Ag Circuit arrangement for regulating the transmission rate with the aid of controlled, non-linear regulating resistors
DE1033716B (en) * 1955-07-28 1958-07-10 Philips Patentverwaltung Circuit arrangement for proper volume control
DE1057650B (en) * 1955-09-29 1959-05-21 Siemens Ag Circuit arrangement to increase the control effect and to expand the control range of an amplifier with negative feedback via a controllable resistor (e.g. controlled hot conductor)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2714635A (en) * 1944-08-07 1955-08-02 Otto H Schmitt Modulator-thermal demodulator system
US2625606A (en) * 1947-11-25 1953-01-13 Bell Telephone Labor Inc Thermistor control circuit
US2754418A (en) * 1949-04-28 1956-07-10 Bendix Aviat Corp Control circuit for a servo system
US2680193A (en) * 1950-06-17 1954-06-01 Bendix Aviat Corp Data smoother
US3159796A (en) * 1961-07-10 1964-12-01 Gen Dynamics Corp Direct current controlled bridge type attenuator

Also Published As

Publication number Publication date
DE613855C (en) 1935-05-29
FR725422A (en) 1932-05-12

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