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VCR TV signal coding system |
price: 265 nominal dollars (VCR-200C) 132 nominal dollars (VCR-200D) 132 nominal dollars (VCR-100D) |
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A coding system is constructed according to the "Line cut&rotate" technology and is considered to be one of the most secure systems. One more peculiarity of this system is that an encoded close-up freeze-frame is not visible. The essence of the coding process is: every line of the visible part is divided into two unequal parts which change their places afterwards: the end part of the line is transmitted at first and the beginning part is transmitted afterwards. A "cut"-point location changes from line to line in a pseudorandom way. The encoded signal of every line is converted by a decoder into a digit string for signal recovery and the line is "cut" in a "point of adhesion" and is "stuck together" in a "cut-point" with the help of digit delay lines afterwards.
Analogous systems are the VTech, produced by VTech Communications Ltd. and the Dalvi Technetix PLC.
The coding system is intended both for CCTVs (the decoder abbreviation is VCR-100D) and for arrangement of commercial TV broadcasting (the decoder abbreviation is VCR-200D). The second variant of the system enables to control the access of each TV network subscriber to the TV channel viewing and provides maintenance of up to 64 TV channels with the quantity of 32000 subscribers. The system can be used in all the frequency ranges of over-the-air and cable TV. There is a Netclient software (Windows 95/98/2000/XP) supplement for commercial TV broadcasting which enables any channel or a channel group tripping of any subscriber (subscriber tripping in case of non-payment). The VCR-200D receiver connection is effected in the following way: a cable with TV program cable is connected to the VCR-200D rf input. The VCR-200D rf output is connected to a TV set . It enables viewing of uncoded TV programmes. The decoded channel signals from the VCR-200D arrive to the "Video" and "Audio" sockets of a TV set (a TV set should be switched over to the AV mode while encoded channel viewing). VCR-200D control to select encoded channels can be effected with the help of control buttons on the front panel and from a TV remote controller. The control can be effected from a TV remote controller. The "training" of the VCR-200D receiver is effected for this purpose in a similar way like it is described in the coding system with frequency jumps.
VCR-200D supply: 12V/400 mA.
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