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Old 3-Jan-2013, 12:03 AM   #21
GroundUrMast
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Re. the various sources of RFI:http://www.tvtechnology.com/conferen...visited/183659

Re. the various sources of RFI, FCC proposed solution (transmitter power level increases by 8 to 12 dB over the VHF spectrum {CH-13 through CH-2}) and the ongoing political pressure to take more spectrum from OTA TV:http://www.tvnewscheck.com/article/4...-high-priority
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Old 3-Jan-2013, 12:05 AM   #22
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Figure 3 and the related cometary are of help: http://www.broadcastpapers.com/white...E6988F127D1403

The implication of this work is that at the bottom of the Low-VHF band, noise levels can be as much as 30 dB higher than thermal noise level.

Last edited by GroundUrMast; 3-Jan-2013 at 12:26 AM. Reason: new link
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Old 26-Jul-2019, 10:40 PM   #23
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Quote:
Originally Posted by GroundUrMast View Post
Figure 3 and the related cometary are of help: http://www.broadcastpapers.com/white...E6988F127D1403

The implication of this work is that at the bottom of the Low-VHF band, noise levels can be as much as 30 dB higher than thermal noise level.
This is an old thread, but the topic is still current because some channels are moving down to VHF-Low as a result of Repack by the FCC.

My measurements with indoor antennas show that the noise on channel 3 is 39 dB above the thermal noise floor (for a 6 MHz channel) and a channel 3 signal must be 33 dB stronger than a UHF channel.

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Old 9-Aug-2019, 5:58 AM   #24
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A quick but worthwhile read: http://www.hdtvexpert.com/tag/low-ba...-tv-reception/
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Old 9-Aug-2019, 11:39 AM   #25
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Good article; thanks for the link.

His noise level (-50 dBm) during a test was even higher than mine.

Pete Putman mentions KSNV on channel 2. In June of 2012 I tried to help a poster in Las Vegas who was having trouble receiving KSNV. I told him it was on VHF channel 2 (virtual 3.1), which it was at the time. He didn't believe me and said it couldn't be on 2.
https://www.avsforum.com/forum/25-hd...las-vegas.html

Quote:
3.1 and 3.2 are digital UHF that I received LAST YEAR in my house a mile south of here with only Rabbit Ears on a ten foot pole, and now can't get them.

If they have gone back to using the vhf low freqs, that wouldn't make sense.
Quote:
OTA includes both digital and analog channels !
The old VHF frequencies, especially 54 to 60 MHZ Is unusable for commercial TV now. Has been for eons because of six meters ham band which I use to work exclusively when I was a teenager and knew John The Baptist!

I quit! ! ! !
He is a ham and retired military commo guy who got so upset that I had to delete my earlier posts to him. After I had something to eat, I tried to explain it to him again.
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