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Old 10-May-2019, 2:40 AM   #21
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,747
Quote:
Originally Posted by OTAFAN View Post
So, if I'm reading your chart correctly rabbit73, obviously you can have a higher noise floor on VHF low particularly, and still receive a watchable signal than either VHF high or UHF? And almost the opposite for UHF?
You almost have it right. Since the noise level IS higher on VHF, you must have a stronger signal on VHF than UHF to have an SNR of at least 15 dB above the noise.

One of the problems with VHF-Low reception of digital TV signals is that the FCC didn't allow enough extra transmitter power to overcome the higher noise level for reliable reception.
Quote:
Forgive my learning curve rabbit73. When I became a shortwave enthusiast years ago, the first thing I learned was as long as I get above the noise floor with my receiver, antenna setup etc., I could "catch" the signal I was looking for. And the quieter my noise floor the better for weak signal reception.

I presume similar for TV viewing? Thanks!
That is correct.
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Last edited by rabbit73; 10-May-2019 at 2:49 AM.
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