GB674635A - Improvements in or relating to radio receivers - Google Patents

Improvements in or relating to radio receivers

Info

Publication number
GB674635A
GB674635A GB1785649A GB1785649A GB674635A GB 674635 A GB674635 A GB 674635A GB 1785649 A GB1785649 A GB 1785649A GB 1785649 A GB1785649 A GB 1785649A GB 674635 A GB674635 A GB 674635A
Authority
GB
United Kingdom
Prior art keywords
transformer
primary
selectivity
signals
formers
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
GB1785649A
Inventor
Roy Victor Browning
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.)
Kolster Brandes Ltd
Original Assignee
Kolster Brandes Ltd
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 Kolster Brandes Ltd filed Critical Kolster Brandes Ltd
Priority to GB1785649A priority Critical patent/GB674635A/en
Publication of GB674635A publication Critical patent/GB674635A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03J—TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
    • H03J5/00—Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner
    • H03J5/24—Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with a number of separate pretuned tuning circuits or separate tuning elements selectively brought into circuit, e.g. for waveband selection or for television channel selection
    • H03J5/242—Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with a number of separate pretuned tuning circuits or separate tuning elements selectively brought into circuit, e.g. for waveband selection or for television channel selection used exclusively for band selection
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H7/00—Multiple-port networks comprising only passive electrical elements as network components
    • H03H7/01—Frequency selective two-port networks
    • H03H7/0153—Electrical filters; Controlling thereof
    • H03H7/0161—Bandpass filters
    • H03H7/0169—Intermediate frequency filters
    • H03H7/0176—Intermediate frequency filters witout magnetic core

Landscapes

  • Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)
  • Amplifiers (AREA)

Abstract

674,635. Selectivity control. KOLSTER BRANDES, Ltd. June 30, 1950 [July 6, 1949], No. 17856/49. Class 40 (v). In the intermediate frequency stage of a receiver adapted to receive A.M. or F.M. signals, a pair of transformers tuned to the appropriate A.M. and F.M. I.F. frequencies are arranged so that the primary of the F.M. transformer can be switched in series with the secondary of the A.M. transformer to vary the selectivity of the latter. With the ganged switches in position 1, the amplifier will pass F.M. signals through the transformer comprising primary 23 and secondary 24 or A.M. signals through the transformer comprising primary 25 and secondary 26. Upon the switches being moved to position 2 the inductor of the F.M. primary 23 is connected in series with the inductor of secondary 26 to increase the coupling in the A.M. transformer and thus decrease the selectivity. Any detuning may be overcome by a variable capacitor. The transformers preferably consist of coils on a former with adjustable magnetic cores for tuning, Fig. 1 (not shown). The coils may be adjustable on the formers and the formers may be moved relative to one another to vary the selectivity further.
GB1785649A 1949-07-06 1949-07-06 Improvements in or relating to radio receivers Expired GB674635A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB1785649A GB674635A (en) 1949-07-06 1949-07-06 Improvements in or relating to radio receivers

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1785649A GB674635A (en) 1949-07-06 1949-07-06 Improvements in or relating to radio receivers

Publications (1)

Publication Number Publication Date
GB674635A true GB674635A (en) 1952-06-25

Family

ID=10102413

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1785649A Expired GB674635A (en) 1949-07-06 1949-07-06 Improvements in or relating to radio receivers

Country Status (1)

Country Link
GB (1) GB674635A (en)

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