JPS6451770A - Afc circuit - Google Patents

Afc circuit

Info

Publication number
JPS6451770A
JPS6451770A JP20817787A JP20817787A JPS6451770A JP S6451770 A JPS6451770 A JP S6451770A JP 20817787 A JP20817787 A JP 20817787A JP 20817787 A JP20817787 A JP 20817787A JP S6451770 A JPS6451770 A JP S6451770A
Authority
JP
Japan
Prior art keywords
circuit
horizontal
synchronizing signal
horizontal synchronizing
inputted
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
JP20817787A
Other languages
Japanese (ja)
Inventor
Shoji Yamaguchi
Kosaburo Morimoto
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.)
NEC Home Electronics Ltd
NEC Corp
Original Assignee
NEC Home Electronics Ltd
Nippon Electric Co 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 NEC Home Electronics Ltd, Nippon Electric Co Ltd filed Critical NEC Home Electronics Ltd
Priority to JP20817787A priority Critical patent/JPS6451770A/en
Publication of JPS6451770A publication Critical patent/JPS6451770A/en
Pending legal-status Critical Current

Links

Landscapes

  • Synchronizing For Television (AREA)

Abstract

PURPOSE:To perform AFC regardless of the kind of an input video signal by supplying it to a phase detection circuit after varying a duty ratio according to a horizontal synchronization frequency. CONSTITUTION:In a case that a horizontal synchronizing signal to be inputted is of a television video signal, a switch circuit 2 selects a first output terminal 2a, and the switch circuit 7 selects a first integration circuit 9. Thus, the phase detection circuit 4 compares the horizontal synchronizing signal HD to be directly inputted and the phase of the saw tooth output SAW of a reference signal generating part, and impresses the output correction voltage to a horizontal oscillation circuit 11 through the integration circuit 9. On the other hand, in the case that the horizontal synchronizing signal to be inputted is of a personal computer video signal, it switches respective switches 2, 7 to other side, and shapes the pulse width of the horizontal synchronizing signal by a shaping circuit 5 so as to make its duty ratio correspond to the horizontal synchronization frequency. Then, the output correction voltage of the phase detection circuit 4 is impressed to the horizontal oscillation circuit 11 through the second integration circuit 10 so that its frequency is controlled.
JP20817787A 1987-08-24 1987-08-24 Afc circuit Pending JPS6451770A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP20817787A JPS6451770A (en) 1987-08-24 1987-08-24 Afc circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP20817787A JPS6451770A (en) 1987-08-24 1987-08-24 Afc circuit

Publications (1)

Publication Number Publication Date
JPS6451770A true JPS6451770A (en) 1989-02-28

Family

ID=16551933

Family Applications (1)

Application Number Title Priority Date Filing Date
JP20817787A Pending JPS6451770A (en) 1987-08-24 1987-08-24 Afc circuit

Country Status (1)

Country Link
JP (1) JPS6451770A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8289566B2 (en) 2000-12-28 2012-10-16 Seiko Epson Corporation Logo data generating method, data storage medium recording the logo data generating method, a computer program product containing commands executing the steps of the logo data generating logo data generating method, and a logo data generating system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8289566B2 (en) 2000-12-28 2012-10-16 Seiko Epson Corporation Logo data generating method, data storage medium recording the logo data generating method, a computer program product containing commands executing the steps of the logo data generating logo data generating method, and a logo data generating system

Similar Documents

Publication Publication Date Title
JPS6481407A (en) Clock signal generating system
JPS5741078A (en) Synchronizing circuit of matrix television
JPS5291637A (en) Frequency conversion system
JPS6451770A (en) Afc circuit
CA2020387A1 (en) Station selecting apparatus
EP0280126A3 (en) Programmable frequency divider and method for generating a low-frequency signal from a high-frequency signal
JPS54124633A (en) Display circuit of television receiver
JPS5717237A (en) Phase synchronizing circuit
JPS57140035A (en) Phase synchronizing oscillation circuit
JPS57162552A (en) Phase synchronizing oscillator of network synchronizing device
JPS57201382A (en) Digital television set
JPS6432795A (en) Television time base correcting device
JPS56103582A (en) Process system of video signal
JPS5552687A (en) Synchronous signal generating device
JPS5441615A (en) Prevention circuit for picture variation
JPS5620355A (en) Clock signal forming circuit
KR920003090B1 (en) Demultiply type synchronization method of power circuit
JPS57103419A (en) Notch rejecting filter
JPS6451712A (en) Clock synchronizing circuit
JPS5453901A (en) Channel selector
JPS57190462A (en) Horizontal deflecting circuit
JPS5248917A (en) Power source unit
JPS55162680A (en) Gate pulse generator
JPS5582568A (en) Afc circuit
JPS5683178A (en) Generating circuit for television vertical deflection signal