WRAL-TV Showcases Next Gen TV’s Potential

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WRAL-TV Showcases Next Gen TV’s Potential

Some interesting points from the article:

MORE POWERFUL & EFFICIENT

"ATSC 3.0’s OFDM modulation scheme is so much easier to receive than ATSC 1’s 8VSB –even at the comparatively low power WRAL is using—that the new standard will make it possible for broadcasters to reach viewers over-the-air using smaller home antennas, on the road and even in their basements, he said."

“It’s a 40kW transmitter that’s covering all of Raleigh,” he explained. “To put that into perspective, this signal is 40kW; WRAL’s main signal is a million [watts ERP].”

Curiouser and curiouser!
 
WRAL-TV Showcases Next Gen TV’s Potential

Some interesting points from the article:

MORE POWERFUL & EFFICIENT

"ATSC 3.0’s OFDM modulation scheme is so much easier to receive than ATSC 1’s 8VSB –even at the comparatively low power WRAL is using—that the new standard will make it possible for broadcasters to reach viewers over-the-air using smaller home antennas, on the road and even in their basements, he said."

“It’s a 40kW transmitter that’s covering all of Raleigh,” he explained. “To put that into perspective, this signal is 40kW; WRAL’s main signal is a million [watts ERP].”

Curiouser and curiouser!
This sounds like it will be easier for all of us to receive an ota signal using ATSC 3.0 new standard. I can’t wait till all you need is some simple rabbit ears like the old days.
 
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This sounds like it will be easier for all of us to receive an ota signal using ATSC 3.0 new standard. I can’t wait till all you need is some simple rabbit ears like the old days.

Yes it definitely sounds exciting. I’ve been awaiting news of what the real-world range of a 3.0 signal would be. To hear that it is dramatically better than what we currently have, sounds very promising.
 
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“It’s a 40kW transmitter that’s covering all of Raleigh,” he explained. “To put that into perspective, this signal is 40kW; WRAL’s main signal is a million [watts ERP].”
The main signal covers more than 40 miles in all directions where the experimental signal is very tightly focused to the northwest. This would seem to be some pretty significant misrepresentation.

Covering Raleigh the city is orders of magnitude different than covering Raleigh the DMA.
 
The main signal covers more than 40 miles in all directions where the experimental signal is very tightly focused to the northwest. This would seem to be some pretty significant misrepresentation.

Covering Raleigh the city is orders of magnitude different than covering Raleigh the DMA.

Where are you seeing the signal pattern of the experimental transmitter?
 
I found this.
At WRAL, ATSC 3.0 Is On The Air - The Broadcast Bridge - Connecting IT to Broadcast
Because Channel 39 is a new channel for WRAL, they bought a new GatesAir 7KW ULXT liquid-cooled UHF transmitter, and an Electronic Research Inc. (ERI) field tunable mask filter.

The antenna feed line is the same transmission line WRAL installed 20 years ago for its ATSC 1.0 experimental broadcasts. Since it was originally installed, station engineers kept the transmission line dry and clean, and it was ready to be used again.

The line is connected to a new ERI panel antenna through the tunable ERI mask filter. The antenna radiates 40 KW ERP horizontal and 30 KW ERP vertical creating an elliptical and directional pattern towards the city while protecting other channels in the market. The antenna’s center of radiation is at 530 meters AGL (1738 feet).
 
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WRAL looks like it would be a very fun place to work right now. They're on the cutting edge. Exciting stuff.

I have to admit I was more than a bit skeptical about 3.0, but seeing real-world implementation has helped me see the light. Plus I have an engineer friend who works for a local TV station and he also says there is a growing excitement about the possibilities with 3.0.
 
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Does the excitement involve the rapid rubbing of hands together against a background of cash registers ringing?
 
In any case, it doesn't seem like a misrepresentation to me. If they'd said it covers in all directions despite being directional, that would be a misrepresentation.
The implication is that the EX channel covers the same area as the TV channel and it absolutely doesn't. TV covers around 17,000 square miles and EX covers less than 5,000 square miles.

To compare coverage of two modulation schemes, only the modulation scheme can change -- not the modulation scheme and the coverage area.

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WRAL-EX
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WRAL-TV
 
If it covers the same part of the area within the area it attempts to cover, then it's an apt comparison. He specifically said coverage over Raleigh, which is the direction of the main beam. I attended a presentation by Pete Sockett last year and they did drive tests of the signal in the area it covers and compared it with the main WRAL signal. Obviously, if a 40 kW signal works and a 1000 kW signal does not, that speaks well of the 40 kW signal, does it not?

(Also, that pattern for WRAL-TV is their aux antenna and is usually not in use. Their main antenna is omni.)

- Trip
 
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Being able to pick up WRAL OTA I am excited to possibly experience this first hand shortly. They have been putting on demonstrations of their ATSC 3.0 signal at NC State that aired recently. If I get access to any tuners they may be providing or offering for purchase I will report back.
 
“Somebody” with a vested interest should be posting videos demonstrating what ATSC 3.0 brings to the table, and not just how it works stuff. Unless they don’t want to tip their hand too early.
 
WRAL has been doing that around here. I am 16 miles from their tower so should be well within the service range. Not sure how much is online but you can see some of the recent ones here. I am also looking to see if they have the package for the demos they gave at NC State online somewhere.
 
He specifically said coverage over Raleigh, which is the direction of the main beam.
While Raleigh is covered, his claim was intended to illustrate something entirely different. The claim was a comparison of relative power required to cover an area. Proponents have long been making a mountain of how ATSC 3.0 will give better coverage but this is absolutely not evidence supporting that claim

This claim was like saying that a 17mm bullet (40kW) makes as big a hole in the target as a 50mm round (1MW) if you only measure 17mm of the hole.
 
I don't think it is a matter of tipping their hand as much as they don't have a lot of real-world data on which to base real-world performance numbers.

At least they have what appears to be one of the finest engineering labs and field test equipment vehicles in the country to come up with those real-world numbers.
 
At least they have what appears to be one of the finest engineering labs and field test equipment vehicles in the country to come up with those real-world numbers.
You concluded that from the article?

I'm keenly interested in how Next Gen performs where the reception isn't almost universally LOS.

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