JPS6454917A - Variable band width band pass filter - Google Patents

Variable band width band pass filter

Info

Publication number
JPS6454917A
JPS6454917A JP21230587A JP21230587A JPS6454917A JP S6454917 A JPS6454917 A JP S6454917A JP 21230587 A JP21230587 A JP 21230587A JP 21230587 A JP21230587 A JP 21230587A JP S6454917 A JPS6454917 A JP S6454917A
Authority
JP
Japan
Prior art keywords
band width
signal
pass filter
band
capacitance
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.)
Pending
Application number
JP21230587A
Other languages
Japanese (ja)
Inventor
Tatsuya Uetake
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.)
Sharp Corp
Original Assignee
Sharp Corp
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 Sharp Corp filed Critical Sharp Corp
Priority to JP21230587A priority Critical patent/JPS6454917A/en
Publication of JPS6454917A publication Critical patent/JPS6454917A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE:To form a Jaunmann type variable band width band pass filter whose band width is controlled by using a varactor diode and a piezoelectric element so as to vary the applied voltage to the varactor diode. CONSTITUTION:In applying a signal to an input terminal 20, a signal passing through a band width determined mainly by the capacitance of varactor diodes 9, 10 and an equivalent constant to an electric circuit with respect to a crystal resonator 2 appears at an output terminal 22 of the Jaumann filter. The capacitance is varied by varying the applied voltage to the diodes 9, 10 thereby varying the band width of a BPF through the action. The result is fed to a high input impedance amplifier 5, where the signal is amplified properly, and the result is given to a resonance circuit in common use with an impedance conversion circuit comprising a capacitor 6 and a transformer 7 with a tap, and a desired signal is obtained from an output terminal 21.
JP21230587A 1987-08-26 1987-08-26 Variable band width band pass filter Pending JPS6454917A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP21230587A JPS6454917A (en) 1987-08-26 1987-08-26 Variable band width band pass filter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP21230587A JPS6454917A (en) 1987-08-26 1987-08-26 Variable band width band pass filter

Publications (1)

Publication Number Publication Date
JPS6454917A true JPS6454917A (en) 1989-03-02

Family

ID=16620365

Family Applications (1)

Application Number Title Priority Date Filing Date
JP21230587A Pending JPS6454917A (en) 1987-08-26 1987-08-26 Variable band width band pass filter

Country Status (1)

Country Link
JP (1) JPS6454917A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4227833C2 (en) * 1991-08-24 1999-11-11 Motorola Gmbh Intermediate frequency filter for a radio receiver
US6653913B2 (en) * 2000-04-06 2003-11-25 Koninklijke Philips Electronics N.V. Tunable piezoelectric filter arrangement using a dielectric material with a voltage-dependent dielectric constant

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4227833C2 (en) * 1991-08-24 1999-11-11 Motorola Gmbh Intermediate frequency filter for a radio receiver
US6653913B2 (en) * 2000-04-06 2003-11-25 Koninklijke Philips Electronics N.V. Tunable piezoelectric filter arrangement using a dielectric material with a voltage-dependent dielectric constant

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