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hongkongpom
hongkongpom, Cable TV Installer
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What is the US Standard, for RF db levels for the home TV

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What is the US Standard, for RF db levels for the home TV? the range is from -2 db to + 10 db or?
Thanks
Don Swartz

Hello and welcome to justanswer.com my name is XXXXX XXXXX I'm here to help you with your TV problem.

 

The FCC mandates that the minimum signal level @75ohms into a TV should be 0dBmV or 3dBmV at the end of a 100' cable.

 

This is equivalent to -48.75dBm

http://www.telsat.com/teltrac.htm

 

The maximum signal you would want would be 10dBmV or -38dBm

 

Here are the rules from the FCC 76.605 technical standards

 

(3) The visual signal level, across a terminating impedance which correctly matches the internal impedance of the cable system as viewed from the subscriber terminal, shall not be less than 1 millivolt across an internal impedance of 75 ohms (0 dBmV).

 

Additionally, as measured at the end of a 30 meter (100 foot) cable drop that is connected to the subscriber tap, it shall not be less than 1.41 millivolts across an internal impedance of 75 ohms (+3 dBmV). (At other impedance values, the minimum visual signal level, as viewed from the subscriber terminal, shall be the square root of 0.0133 (Z) millivolts and, as measured at the end of a 30 meter (100 foot) cable drop that is connected to the subscriber tap, shall be 2 times the square root of 0.00662(Z) millivolts, where Z is the appropriate impedance value.)

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