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Hikvision Tvi

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Hi I am looking at purchasing Hikvision Tvi equipment. Is Tvi classed as digital cctv?

 

These are the two products I am interested in:

 

http://www.hikvision.com/en/Products_accessries_179_i5828.html

 

http://www.hikvision.com/en/Products_accessries_364_i5791.html

 

Anyone have experience of these? I'd love to hear any opinions before I click the purchase button.

 

Thank you

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Yes [AFAIK], TVI is hi-def[digital] over analog cables -- one of several 'protocols'.

 

Not an expert but am learning, those 'in the know' will provide more info.

 

HikVision seems to be a very solid provider of digital camera systems. I did not even know they did AHD, was only aware of the POE NVRs and cameras. Looks like it only supports three technologies though [TVI, AHD and analog]

 

Thanks for the links/info.

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Just for the record HD-TVI is NOT a digital signal as transmitted on a cable. It has a Sync pulse, back porch with color burst, White area and chroma information just like the analog video of old. The big difference is the Sync rate is more than doubled to handle the higher picture pixels, and most important the chroma carrier and information is set at a much higher frequency around 29MHz in the spectrum. HD-CVI is also an analog signal, not digital on the cable and both are designed to use 75 Ohm cable. Take a look at the signal on an oscilloscope and you will see what I mean.

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Just for the record HD-TVI is NOT a digital signal as transmitted on a cable. It has a Sync pulse, back porch with color burst, White area and chroma information just like the analog video of old. The big difference is the Sync rate is more than doubled to handle the higher picture pixels, and most important the chroma carrier and information is set at a much higher frequency around 29MHz in the spectrum. HD-CVI is also an analog signal, not digital on the cable and both are designed to use 75 Ohm cable. Take a look at the signal on an oscilloscope and you will see what I mean.

 

C vi is digital and Will run over any cable .... Coax ...alarm cable ....cat5. Even over 1 pair

 

Cvi will run multiple cameras over 1 coax .....made easy as a digital signal

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The HD-CVI camera format is an analog signal also. It is called Composite Video Interface because it is in fact a Composite of a Sync signal at a higher rate to start the video line, a color burst to synchronize the chroma (color) carrier, a white area just like the analog signal but at a higher rate to fit all the pixels. The Color carrier for the CVI signal is in the 21MHz region as seen on a spectrum analyzer. Both the TVI and CVI signals have a vertical interval also with serrated pulses just like the analog signals of old for vertical blanking. If they were digital signals you would not be able to see any of these things on an oscilloscope. Take a look, you will be surprised. Both the TVI and CVI formats are pure analog High Definition.

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The HD-CVI camera format is an analog signal also. It is called Composite Video Interface because it is in fact a Composite of a Sync signal at a higher rate to start the video line, a color burst to synchronize the chroma (color) carrier, a white area just like the analog signal but at a higher rate to fit all the pixels. The Color carrier for the CVI signal is in the 21MHz region as seen on a spectrum analyzer. Both the TVI and CVI signals have a vertical interval also with serrated pulses just like the analog signals of old for vertical blanking. If they were digital signals you would not be able to see any of these things on an oscilloscope. Take a look, you will be surprised. Both the TVI and CVI formats are pure analog High Definition.

 

You right

but for example 720p/60Hz transmission the carrier is at 58.559489MHz

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