GB1529918A - Mf/vf receivers - Google Patents

Mf/vf receivers

Info

Publication number
GB1529918A
GB1529918A GB1860176A GB1860176A GB1529918A GB 1529918 A GB1529918 A GB 1529918A GB 1860176 A GB1860176 A GB 1860176A GB 1860176 A GB1860176 A GB 1860176A GB 1529918 A GB1529918 A GB 1529918A
Authority
GB
United Kingdom
Prior art keywords
path
terminal
volume control
automatic volume
selective circuits
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
GB1860176A
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 GB1860176A priority Critical patent/GB1529918A/en
Publication of GB1529918A publication Critical patent/GB1529918A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q1/00—Details of selecting apparatus or arrangements
    • H04Q1/18—Electrical details
    • H04Q1/30—Signalling arrangements; Manipulation of signalling currents
    • H04Q1/44—Signalling arrangements; Manipulation of signalling currents using alternate current
    • H04Q1/444—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies
    • H04Q1/45—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling
    • H04Q1/453—Signalling arrangements; Manipulation of signalling currents using alternate current with voice-band signalling frequencies using multi-frequency signalling in which m-out-of-n signalling frequencies are transmitted

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Tone Control, Compression And Expansion, Limiting Amplitude (AREA)

Abstract

1529918 Tone receivers; automatic volume control STANDARD TELEPHONES & CABLES Ltd 6 May 1976 18601/76 Heading H4K In a voice frequency receiver a feed forward automatic volume control circuit is provided prior to the frequency selective circuits. In a first embodiment, Fig. 3, the input signal is divided into two paths, the first path being connected directly to terminal IP whereas the second path is connected via a rectifier, not shown, to terminal IP2. The control potential on field effect transistor FT therefore varies with the level of the incoming signal to keep the input to operational amplifier OA substantially constant in amplitude. In a further arrangement (Fig. 21, not shown) the rectified signal is applied to a voltage controlled attenuator. The AGC arrangement may be provided between each band pass filter and the respective frequency selective circuits in a 2 times 1 out of 4 dual frequency receiver (Fig. 1, not shown).
GB1860176A 1976-05-06 1976-05-06 Mf/vf receivers Expired GB1529918A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB1860176A GB1529918A (en) 1976-05-06 1976-05-06 Mf/vf receivers

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1860176A GB1529918A (en) 1976-05-06 1976-05-06 Mf/vf receivers

Publications (1)

Publication Number Publication Date
GB1529918A true GB1529918A (en) 1978-10-25

Family

ID=10115262

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1860176A Expired GB1529918A (en) 1976-05-06 1976-05-06 Mf/vf receivers

Country Status (1)

Country Link
GB (1) GB1529918A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0521653A2 (en) * 1991-07-01 1993-01-07 Raytheon Company Gain control amplifier

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0521653A2 (en) * 1991-07-01 1993-01-07 Raytheon Company Gain control amplifier
EP0521653A3 (en) * 1991-07-01 1993-06-16 Raytheon Company Gain control amplifier

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Legal Events

Date Code Title Description
PS Patent sealed
746 Register noted 'licences of right' (sect. 46/1977)
PCNP Patent ceased through non-payment of renewal fee