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  #16  
Old 11-03-2017, 10:16 AM
philcophan philcophan is offline
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DTV has it's pluses and minuses for certain. Here in Allentown, we have channel 2, KJWP, on the same stick as all the other channels, yet it craps out exactly at sunset... it may or may not return as the evening continues... go figure. Their power is minimal in my estimation... like 7.6kw or something like that. Channel 6, WPVI, has been absent since the transition but ABC, for what it's worth (nothing), is available on 16 from Scranton. My BIGGEST gripe is move the antenna a degree or two and you lose it... must be aimed dead nuts on!!! My antenna is the biggest whopper Antennacraft ever made, the Discovery D9000, I think is the model. I have another and am considering stacking two.
My buddy lives 14 miles south of me on a higher area and receives NY, Philly, Baltimore and sometimes Washington reliably... I'm thinking the higher and bigger the better... YMMV...

Jim
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  #17  
Old 11-04-2017, 05:40 PM
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benman94 benman94 is offline
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Well I have a bit of egg to wipe off of my face... My grandparents called me, irate that their TV set was on the fritz again. I went over to look at the situation and discovered that only channel 28 WCMZ was coming in. I dragged along a small table top flatscreen, hooked it directly up to the antenna, and discovered that all of the Detroit stations, all of the Flint/MBS stations, and all but one of the Lansing stations were coming in fine.

To make a long story short, I had a newer section of quad shield RG-6 (that I had replaced when changing the antenna out) that had more than likely been bad from day one and was only getting progressively worse. The moral of the story? Don't trust that anything has been manufactured correctly. I replaced a 25 foot section of wire inside the house and now they have more stations than they had in the analog era.

They still can't get WILX, which they could get before the analog shutoff, but the new stations more than make up for it. I owe Wayne and the others involved in the DTV standards development a qualified apology; VHF performance with DTV is less than ideal, but it's a hell of a lot better than I thought it was. This does bring up another point though, trouble shooting with analog was much easier than it is with the DTV standard.

Anyway, I'm sorry guys.

Last edited by benman94; 11-04-2017 at 06:27 PM.
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  #18  
Old 11-04-2017, 06:33 PM
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old_tv_nut old_tv_nut is offline
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Originally Posted by benman94 View Post
...This does bring up another point though, trouble shooting with analog was much easier than it is with the DTV standard.
...
For sure. One of the inventors of digital VSB liked to say that "analog is the window on the RF world." The problem is that you don't see varying quality as you adjust an antenna or repair a RF feed - the picture is only there or not there, and you have no idea how much head room you have above the threshold. Some manufacturers have attempted tuning aids that give some sort of signal quality indication, perhaps combining both signal strength and ghost energy, but this has been only modestly successful as far as I know.
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  #19  
Old 11-04-2017, 08:00 PM
Colly0410 Colly0410 is offline
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Here in England it's all UHF & has been for 40 odd years. Digital is rock solid now they've upped the power after analog closedown. My local transmitter (Waltham) used to be 250 Kw's TX'ing 5 channels in the analog days; it's now 50 Kw's for HD & public service (BBC, ITV, ch4 ch5 etc) SD Multiplex's; 25 Kw's for other commercial SD mux's; (Quest, CBS, 5 USA. Food network, Tru TV etc) 5 Kw's for local Nottinghamshire TV station, (with a very directional TX ant) 10.2 Kw's for a mux carrying Viva, Russia today, Al Jazeera etc; & 13.4 Kw's for a mux carrying 5*, More 4+1 & some pay channels. I get all these mux's with no breakup or dropouts with a UHF ant resting on top of the central heating water feed tank in the loft..
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  #20  
Old 11-04-2017, 10:44 PM
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The Zenith DTV converter boxes (IIRC 900/901) have a great signal strength indicator. I always like to use them for setting up an antennas and or DXing.
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  #21  
Old 11-06-2017, 09:28 PM
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DTV may have issues as far as reception range, etc. is concerned, but the picture quality from DTV stations rivals NTSC many times over. I remember watching TV in 4:3 aspect ratio from the '60s until the DTV switch in 2009, and am nothing short of amazed at the improvement in picture quality (over NTSC) afforded by the ATSC standard. I have a 19" flat-screen HDTV that produces a picture sharper and clearer than I ever saw on NTSC analog. I watch my area's local channels via streaming video (Roku), and, again, am very impressed by the much sharper/clearer picture afforded by DTV; needless to say, I would never go back to NTSC analog, even if I could.

DTV's reception problems are here to stay in most areas, due to the lower ERP power (compared to NTSC) of local stations. The use of an outdoor TV antenna, cable, or satellite is almost mandatory to receive consistently good pictures from DTV stations. Of course, if you want to sidestep these issues, you can--by using devices such as Roku, Google TV, Apple TV and other streaming-video boxes. "Cord cutting" has become very popular in the US, much to the dismay of the cable companies. The number of cable subscriptions, in fact, has dropped dramatically since the introduction of streaming-video players such as the ever-popular Roku, et al., which is no doubt making the nation's cable operators very nervous as to their future survival in the 21st century. As cable TV subscription prices continue to rise (and the quality of said service declines at the same time in many cases), I see many cable operators scaling back their services or, at worst, going out of business entirely. Many people, myself included, do not like the idea of using a cable box ahead of their TV (to say nothing of paying outrageously high cable-TV bills), so I think the sales of OTA TV antennas and streaming-video devices will continue, as strong as or stronger than ever, as they have for some time.

Will streaming video eventually kill cable and satellite TV? Only time will tell, although, as I said, the increasing popularity of the Roku and other SV boxes means fewer subscribers, which is not good news by any means for pay-TV providers. Then again, perhaps cable and satellite TV may have seen better days, and it could be time to move on to better technologies.
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  #22  
Old 11-29-2017, 10:32 PM
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Robert Grant Robert Grant is offline
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When discussion of HDTV started getting serious in the early nineties, the plan was for all over-the-air television to migrate to UHF on channels 14-69, with VHF television to be discontinued.

Then. Congress got greedy. They added high-VHF (7-13) to the plan, in order to sell channels 63-69 to cellular interests. Quite quickly, they added low-VHF (2-6) as well, leaving channel 58 as the top channel. Later, channels 52-58 were cut out of the plan.

Well, when the VHF channels were added to the plan, the FCC worried that the DTV stations on VHF would have an "unfair advantage" of greater coverage compared to UHF stations (as lower frequencies do carry further over the cuvature of the Earth). Thus, lower power levels were prescribed for VHF high stations and much lower power levels were prescribed for low-VHF stations.

This had the drawback that high-VHF stations would have weaker signals in areas that were NOT on the fringe, and low-VHF stations would have MUCH weaker signals.

Go to rabbitears.info, and look at the longley-rice coverage maps of any lowband DTV, and you'll see a lot of red and orange shades!

To make matters worse, the early years of the DTV transition coincided with an electronics revolution that filled the spectrum with an unbelievable surge in the amount of RFI in the VHF bands.

How bad VHF is for DTV depends on where you live. While the power levels for UHF are the same throughout the US, VHF power levels are divided into zones. In areas where many cities are packed close together, low-VHF stations are limited to a paltry 10kW and high VHF are allowed a maximum 30kW (and many of these are limited further). In the rest of the country, lowband stations are allowed up to 45kW if their towers are not very tall, and highband stations with short towers may be as powerful as 160kW!

Finally, antenna manufacturers had heard that all TV was going to UHF and didn't get the memo when Congress shifted the TV bands (to this day, I hear from people who insist that all TV is UHF now), so a lot of people buy cute little antennas, and wonder why they're not getting all of the local stations.

Last edited by Robert Grant; 11-29-2017 at 11:27 PM.
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  #23  
Old 10-12-2020, 06:54 PM
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Quote:
Originally Posted by Robert Grant View Post
Finally, antenna manufacturers had heard that all TV was going to UHF and didn't get the memo when Congress shifted the TV bands (to this day, I hear from people who insist that all TV is UHF now), so a lot of people buy cute little antennas, and wonder why they're not getting all of the local stations.
I recently had my roof reshingled. So I moved my Winegard HD7084P into the attic. Boom length 131", max width 110". Getting it through the little trap door in the closet and reassembling it in the attic was like building a ship in a bottle. I didn't know about the repacking and was thinking about replacing it with something more UHF focused. But I wanted to keep the FM radio capability, so I made the effort to stay with the Winegard. Glad I did.
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  #24  
Old 10-13-2020, 04:10 AM
Titan1a Titan1a is offline
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My UHF reception is plagued with Doppler shift from nearby trees. On calm days or in the winter all is well. Either live with it or raise the mast.
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  #25  
Old 10-13-2020, 08:52 AM
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ATSC over the air is finicky to begin with, UHF or VHF. Especially if trees, terrain issues, or more than 30 miles out. If VHF had the same power it did in the days of analog, the situation would have been better for VHF DTV.

Last edited by KentTeffeteller; 10-18-2020 at 09:24 AM.
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  #26  
Old 10-13-2020, 10:53 PM
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My area has channels 3, 5, 8, 19, 23, 25, 43 and 61, all but one transmitting from a western suburb of Cleveland. (Channel 23 is in Akron, sixty miles from Cleveland.) Where I live, a small village some 40 miles from the TV stations, I can get all but channels 8, 19 and 43 using an indoor antenna. All three stations operate with low transmitter power on their original channels (they did not move to UHF as did the others), which means my TV's channel scan skips right past them when I scan for my locals. I live in an apartment building, so cannot use an outdoor antenna for TV, ham radio or anything else (lease restrictions). Moving to a house is out of the question for me as well, since I live on a fixed income (very long story and OT).
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Last edited by Jeffhs; 10-13-2020 at 11:57 PM.
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  #27  
Old 11-06-2020, 11:50 AM
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VHF could use some more power based on previous posts. The VHF signals seem to be better if you live in a hole, boxed in by trees that will block/scatter UHF way more.

My experiences upstate at the cabin bear this out. Fortunately we have a good spot, higher and facing an open meadow. Using a Winegard HD7697 and preamp. All comes in good there, not strong but stable, two VHF signals on 7+8 from Binghampton NY are good using a channel 8 - 10-element yagi and no amp. Binghampton has 2 UHF stations WIVT being one of them but neither can be locked in as one transmits from a different location than 7+8. Elmira/corning we get only WETM, from another direction than the others but fairly stable signal.

Even at 38 air miles away from Penobscot Mtn, it is not equally good in the area. UHF from Scranton-Wilkes Barre is now on 21 and 22, while VHF is on 11 and 12.

6 miles south, my neighbor has a cabin in a low, boxed-in area just up from a creek bed. At his place, same antenna and amp brought in nothing (U or V) from Penobscot, being far down the back side of a hilltop. Walking and climbing ladders did little. An 8-bay bowtie UHF turned up nothing as well.

The Winegard 7697 did however pull in Binghampton's two VHF transmitters which is 56 miles away, along a tree-lined creek valley - bit open in that direction. I found a YA-1713 from Antennacraft and thats what they use now. UHF was always a no show deep in the woods. Before the analog shut down, their only channel was WBNG-12, like most folks in the area.
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Last edited by DavGoodlin; 11-12-2020 at 07:59 AM. Reason: UHF from Bing a no-show
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  #28  
Old 04-25-2021, 10:41 AM
pgnl pgnl is offline
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It will be interesting to learn whether or not ATSC 3.0 NextGen TV improves the situation. My understanding is ATSC 3.0 uses COFDM with multiple carriers unlike VSB in ATSC 1/2. In the UK DVB-T and DVB-T2 uses COFDM, the former with up to 8000 carriers and the latter with up to 32000 carriers, presumably this method evens out and helps eliminate interference. DVB-T was first used in the UK for SD in 1997 and DVB-T2 for HD in 2010.

I remember reading when ATSC was adopted and chosen over DVB-T, that broadcast conditions in the US are very different and over longer distances to many other countries, which presumably why it was selected - in addition to of course the US wanting to use its own developed system.

I have never actually seen an ATSC HD picture, but assume like DVB-T2 with HD it is pretty rock solid. Someone mentioned MPEG2 artifacts, the UK uses MPEG2 for SD on DVB-T and MPEG4 for HD on DVB-T2. Germany broadcasts HD/UHD using HEVC on DVB-T2..

Patrick, UK
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  #29  
Old 04-25-2021, 11:11 AM
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ATSC 3.0 performance is very similar to DVB-2. ATSC 1/2 was chosen mainly due to its superior signal to noise performance compared to DVB with similar data rate. This was a priority to allow the simulcast of ATSC and NTSC in the US environment where common practice was "big stick" broadcasters, each covering a large geographic area. At the time, DVB decoders were still experimental and could not demonstrate the promised ghost canceling capability. (That changed in a couple of years, of course.) By the time the two systems came into actual use, DVB decoders were more capable of handling diffuse ghosts with a smeared range of delays, and rapidly moving (Doppler) ghosts, than ATSC, if the DVB parameters were set by the broadcasters to favor those conditions. However, ATSC still was superior regarding signal to noise ratio. Now that NTSC is shut down, that advantage is less important, although the FCC never raised the ATSC signal levels as they could have after NTSC was gone.

ATSC 3.0, like DVB-2, can take advantage of new broadcast arrangements like single-frequency networks. and likewise has adjustable parameters that can trade data rate for Doppler (mobile) and signal-to-noise (hand-held receiver) performance.
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  #30  
Old 04-25-2021, 12:32 PM
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As n aside, in the NTSC days, was UHF ever NOT finicky? I don't ever recall being able to get UHF decently..
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