JPS56115081A - Video switching circuit - Google Patents

Video switching circuit

Info

Publication number
JPS56115081A
JPS56115081A JP1874380A JP1874380A JPS56115081A JP S56115081 A JPS56115081 A JP S56115081A JP 1874380 A JP1874380 A JP 1874380A JP 1874380 A JP1874380 A JP 1874380A JP S56115081 A JPS56115081 A JP S56115081A
Authority
JP
Japan
Prior art keywords
circuits
switches
video
groups
impedance
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
JP1874380A
Other languages
Japanese (ja)
Inventor
Hideo Akiyama
Ichiji Munesawa
Toshihiko Tsuru
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 Corp
Original Assignee
NEC Corp
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 Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP1874380A priority Critical patent/JPS56115081A/en
Publication of JPS56115081A publication Critical patent/JPS56115081A/en
Pending legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00Details of television systems
    • H04N5/222Studio circuitry; Studio devices; Studio equipment
    • H04N5/262Studio circuits, e.g. for mixing, switching-over, change of character of image, other special effects ; Cameras specially adapted for the electronic generation of special effects
    • H04N5/268Signal distribution or switching

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Studio Circuits (AREA)

Abstract

PURPOSE:To reduce the deterioration of characteristics and increase the number of output circuits, dividing a plural number of video switches into a plural number of groups, securing the equal transmission lines that connects between the input circuits and the grouped switches and then supplying the video signals via more than two lines of high impedance. CONSTITUTION:The video signals are received by the input circuits 1-3 and then branched into two parts to be supplied to the high-impedance line groups 10 and 11. The video switches 4-6 are connected to the groups 10 and 11 each. Then the signals branched into two parts are supplied to the switches 4-6 plus 7-9, and a difference of 1/2 or less is secured for both the frequency characteristics and the phase between the supply points A and A' close to the circuits 1-3 and the supply points B and B' distant away from the circuits 1-3. Furthermore the impedance compensating coil L, the phase control capacitor C and the termination resistance R are provided to the circuits 1-3 to secure a phase control among the inputs. Thus the deterioration of characteristics is reduced, and at the same time the number of output circuits are increased.
JP1874380A 1980-02-18 1980-02-18 Video switching circuit Pending JPS56115081A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1874380A JPS56115081A (en) 1980-02-18 1980-02-18 Video switching circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1874380A JPS56115081A (en) 1980-02-18 1980-02-18 Video switching circuit

Publications (1)

Publication Number Publication Date
JPS56115081A true JPS56115081A (en) 1981-09-10

Family

ID=11980129

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1874380A Pending JPS56115081A (en) 1980-02-18 1980-02-18 Video switching circuit

Country Status (1)

Country Link
JP (1) JPS56115081A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58159085A (en) * 1982-03-17 1983-09-21 Nec Corp Processing device of digital video signal
JPS61105988A (en) * 1984-10-30 1986-05-24 Nippon Telegr & Teleph Corp <Ntt> Television lecturing device

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58159085A (en) * 1982-03-17 1983-09-21 Nec Corp Processing device of digital video signal
JPH0145797B2 (en) * 1982-03-17 1989-10-04 Nippon Electric Co
JPS61105988A (en) * 1984-10-30 1986-05-24 Nippon Telegr & Teleph Corp <Ntt> Television lecturing device

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