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  #16  
Old 11-03-2017, 11:16 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...

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  #17  
Old 11-04-2017, 06:40 PM
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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 07:27 PM.
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  #18  
Old 11-04-2017, 07:33 PM
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Quote:
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, 09:00 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, 11:44 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, 10:28 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, 11:32 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; 11-30-2017 at 12:27 AM.
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