JPS57141186A - Descrambling device for video signal transmission - Google Patents

Descrambling device for video signal transmission

Info

Publication number
JPS57141186A
JPS57141186A JP56206752A JP20675281A JPS57141186A JP S57141186 A JPS57141186 A JP S57141186A JP 56206752 A JP56206752 A JP 56206752A JP 20675281 A JP20675281 A JP 20675281A JP S57141186 A JPS57141186 A JP S57141186A
Authority
JP
Japan
Prior art keywords
signal
circuit
video signal
exponential function
amplitude
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.)
Granted
Application number
JP56206752A
Other languages
Japanese (ja)
Other versions
JPS5820191B2 (en
Inventor
Yoshibumi Saeki
Hiroki Uemura
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.)
Pioneer Corp
Original Assignee
Pioneer Corp
Pioneer Electronic 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 Pioneer Corp, Pioneer Electronic Corp filed Critical Pioneer Corp
Priority to JP56206752A priority Critical patent/JPS5820191B2/en
Publication of JPS57141186A publication Critical patent/JPS57141186A/en
Publication of JPS5820191B2 publication Critical patent/JPS5820191B2/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N7/00—Television systems
    • H04N7/16—Analogue secrecy systems; Analogue subscription systems
    • H04N7/167—Systems rendering the television signal unintelligible and subsequently intelligible
    • H04N7/171—Systems operating in the amplitude domain of the television signal

Landscapes

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

Abstract

PURPOSE:To prevent the generation of a residual ripple component and to improve picture quality by performing amplitude demodulation by a decoding signal processed previously by exponential function modulation when desrambling a scrambled video signal. CONSTITUTION:At a transmission side 1, part of an RF video signal is led out and a horizontal synchronizing signal component is extracted to generate a sine- wave signal whose phase is adjusted; and it is applied to an exponential function circuit 8 to generate an encoding signal and after impedance conversion by a driving circuit 9, an RF video signal as an input signal to be modulated is processed through the amplitude modulation of an amplitude modulating circuit 10 to send the resulting signal to a repeating transmission line 30. A decoding signal is amplified by a narrow band amplifier 24 and, after phase adjustment, is applied to an exponential function circuit 26 which has input and output characteristics similar to hose of the circuit 8. The output of the circuit 26 is applied to an amplitude modulating circuit 28 to descramble the RF video signal.
JP56206752A 1981-12-21 1981-12-21 Descrambling device for video signal transmission Expired JPS5820191B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP56206752A JPS5820191B2 (en) 1981-12-21 1981-12-21 Descrambling device for video signal transmission

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP56206752A JPS5820191B2 (en) 1981-12-21 1981-12-21 Descrambling device for video signal transmission

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
JP50119273A Division JPS5818832B2 (en) 1975-10-02 1975-10-02 Scrambling device for video signal transmission

Publications (2)

Publication Number Publication Date
JPS57141186A true JPS57141186A (en) 1982-09-01
JPS5820191B2 JPS5820191B2 (en) 1983-04-21

Family

ID=16528501

Family Applications (1)

Application Number Title Priority Date Filing Date
JP56206752A Expired JPS5820191B2 (en) 1981-12-21 1981-12-21 Descrambling device for video signal transmission

Country Status (1)

Country Link
JP (1) JPS5820191B2 (en)

Also Published As

Publication number Publication date
JPS5820191B2 (en) 1983-04-21

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