JPS5539441A - Adjacent channel stealthy glance preventing device for catv system - Google Patents
Adjacent channel stealthy glance preventing device for catv systemInfo
- Publication number
- JPS5539441A JPS5539441A JP11283378A JP11283378A JPS5539441A JP S5539441 A JPS5539441 A JP S5539441A JP 11283378 A JP11283378 A JP 11283378A JP 11283378 A JP11283378 A JP 11283378A JP S5539441 A JPS5539441 A JP S5539441A
- Authority
- JP
- Japan
- Prior art keywords
- signals
- circuit
- adjacent channels
- stealthy
- channel
- 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
Links
Abstract
PURPOSE: To prevent the stealthy glance through the adjacent channels by giving positively the disturbance to the adjacent channels.
CONSTITUTION: The signals are sent to input signal terminal 1 from the CATV broadcast station. The input signals are grouped through branching circuit 2 into the data communication signals and the TV channel signals. The TV channel signals are converted into the output channel via frequency conversion circuit 3, and the data communication signals are smplified at amplifier circuit 5 to be delivered to line 9 through branching circuit 6 for the signal process. And the other branched output is applied to divider circuit 7 for prevention of the stealthy glance. The signals divided at circuit 7 are turned to the signals of about 60.625MHz, which are the signals extremely approximate to the adjacent channels to be used as the stealthy preventing signals. These signals, after removal of the side band through filter 8, are mixed with the output channel at adder circuit 4 to be sent to output terminal 10. Thus the adjacent channels cannot produce a high-quality picture image.
COPYRIGHT: (C)1980,JPO&Japio
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP11283378A JPS5539441A (en) | 1978-09-13 | 1978-09-13 | Adjacent channel stealthy glance preventing device for catv system |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP11283378A JPS5539441A (en) | 1978-09-13 | 1978-09-13 | Adjacent channel stealthy glance preventing device for catv system |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS5539441A true JPS5539441A (en) | 1980-03-19 |
Family
ID=14596666
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP11283378A Pending JPS5539441A (en) | 1978-09-13 | 1978-09-13 | Adjacent channel stealthy glance preventing device for catv system |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5539441A (en) |
-
1978
- 1978-09-13 JP JP11283378A patent/JPS5539441A/en active Pending
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