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Old 20-May-2016, 10:54 PM   #10
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,507
Quote:
Originally Posted by user name View Post
In the Phila., pa. area,

Channel 6 broadcasts at the end of the FM band
Channel 2 and 12 on the VHF band
The other channels on the UHF band

After scanning, channels 2 and 12 were _NOT_ detected!
Channel 6 was detected!

I did a second scan.
Channel 2 was not detected but channel 12 was.
But channel 12 is too weak to watch.

Channel 12 is a green channel and weaker than 2 according to the tvfool TV Signal Analysis.
You have made 16 posts and we still haven't seen your tvfool report. At least you finally told us Philadelphia PA so that we have a rough idea of what you are talking about.

The noise level on VHF-Low, real channels 2-6, is higher than on VHF-High. A much stronger signal is needed on 2 than on 12 to overcome the noise. The tvfool report does not take that into consideration. Channel 2 CBS in Chicago was such a problem they had to move up to channel 12.

It is not just how strong it is, but how strong it is in comparison to the noise level, which is mostly from electrical interference. The signal must be at least 15 dB stronger than the noise. This is calld SNR, or Signal to Noise Ratio.

Quote:
I heard that about 5% of the us population watches over the air tv.
I heard that it is more than twice that.
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Last edited by rabbit73; 20-May-2016 at 10:59 PM.
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