Question about new digital tv in The States and weather?

[freebird73717]

Okay. I have directv satellite service. I also have always had an analog/digital combo tv antenna setup outside my house as a backup so that I can watch the news during a storm ( whenever we have a rainstorm I lose satellite signal). My tv has an digital tuner built in so getting digital signals are not a problem (and man do they look good).

My question is that when analog goes dark and the digital switch happens in feb. will my digital antenna suffer the same signal lose that my satellite does when there is a rain storm?

[usually_quiet]

For the most part, I wouldn't think so. I have rabbit ears, so it's not quite the same as an outdoor antenna, but only the channels that are marginal anyway are affected in any way by the weather.

[yoda313]

Don't forget digital has a termination distance unlike analog. Once you're beyond its reach its dropped. You won't get fuzzy weak signals like analog. Its all or nothing.

Also always use powered antennas for any hdtv use. Unpowered ones generally don't have the power for a stable digital signal (at least the ones I've used don't).

(now this is based on some stuff I read a few years ago, have they changed how far digital signals travel compared to analog?).

[usually_quiet]

Amplified antennas are not necessary if you are close to the transmitter, and may cause problems in that case. I'm only 9 miles from most of them.

[yoda313]

Amplified antennas are not necessary if you are close to the transmitter, and may cause problems in that case. I'm only 9 miles from most of them.

Well I did find I needed to adjust the gain on my amplified antenna to keep the signal stable. Once I moved it around a bit I got it just fine.

[usually_quiet]

With an antenna, it's always location, location, location, and I'm lucky enough to be in a good spot for reception. If somebody needs amplification, they need it, but there is no reason to get it when it isn't required. I think it is better to find out if amplification will be useful first, rather than make a blanket recommendation to get it. If the gain has to be turned down all the time, it's a waste of money.

An amplified antenna was not worth the extra money in my case. In good weather, if the rabbit ears are sitting in the right place, I can get good reception for 17 digital channels. According to a recent local program about the digital transition, that is the most that anybody in the area can reasonably expect to get, even with a good outdoor antenna and amplification.

In bad weather I loose a couple of them, but they are 50 miles away, and they come in better as digital stations than they did as analog. Most of the programming they have is duplicated by one of the stronger channels, so I can easily do without them.

I suppose that the OP's local stations might not have begun offering digital service, or are not broadcasting at full power yet, but otherwise it should be possible to get an idea of what reception is like with his present antenna.

[vhelp]

You'll have interuped/brakeage in the picture. This will be seen as partial picture and what usually looks to be mpeg pixelation though they are mpeg decoding errors because the signal cannot be completely read and decoded 100 percent. I'm sure there is a better term for this, but the bottom line is you will suffer the same or similar effect of, either no picture or interuped picture. It like the signal is strong and weak, pending how the weather affects the signal.

Its been posted here that in Feb/2009, the wattage will be raised. Personally, I don't believe that. It doesn't make any sense to lower/raise wattage as one sees fit. However, take for instance, NBC. I could not get them ever. Then, when the 2008 olympics came on, I could receive them near 100 percent, minus a few glitches in the signal which resulted in picture breakage here and there. And, certain times of the time, usually morning, no signal. Then, in the evening, it would come back again, sometimes near 90 percent, give or take.

Today, I can not get NBC no matter where I position the anntenna. In fact, I used to get ABC months ago. It was one of the channels I used to get in regulary. Now, since before the 2008 Olympics, I could not get it in, and to this day, not even ABC is coming in. Its like someone turned off the switch. Nothing comes in. So, I don't know what's going on. After getting tired and fed up with it, I haven't touched the OTA antenna nor the HD capture card in the last month, and I'm too lazy to bother playing with it at this time.

But, as for me, since we don't have the two towers antenna anymore, and since the empire state building antenna (if that is the antanna being used now) is too far away from me--I don't get any New York stations down that way, roughly 40 miles away, I think..that it will be a very long time that I (in my general area) will be receiving any HD channels anytime soon when feb/2009 hits and they turn on the switch. I will be in the same situation as I am today, no channels.

Now, assuming that its true that this wattage thing is set to low on purpose, and if connecticut is a part of that scenario, if they do raise the wattage, I may get those two (and other channels) clear. I don't know. I only know that sometimes certain channels come in, some strong and some weak, and some at different seasons. I just don't know how this will all pan out in feb/2009. I am hoping for better, otherwise I analog cabletv better be around for much longer

-vhelp 4957

:P *~*!*~*!~* HaPpY HoLiDaY *~*!*~*!~*

[edDV]

There is the general case, plus local issues and special transition cases like NYC (Empire State Building) and San Francisco (Sutro Tower).

In general, digital ATSC goes similar distance to a NTSC at similar power but behaves differently at the limits. Analog fades to snow and noisy audio, where digital struggles with error correction (resulting in some pixelation) then drops to nothing. If weather is causing fade in/out, ATSC will cut in and out. When it is in, the picture quality will be good. You will see pixelation just before the signal drops. Most tuners will wait for a reasonably strong signal before it comes back.

Local issues may cause weather or seasonal issues. If you are behind a hill and getting ATSC from a multi-path bounce, then weather will cause much disruption. Amps may make this worse because they amplify multiple bounced signals as much as the direct signal. For this reason, amplifiers work best with directional antennas.

As an example of local issues, the CA Central Valley has seasonal problems that occur during winter ground fog. San Francisco stations off Sutro tower disappear during winter months for those in low elevations where those higher up get great reception. Heavy snow or rain may cause temporary signal loss.

Most large market DTV stations are currently operating from temporary transmitters and antennas until Feb 17. Most of those will switch to new equipment at higher power (often on different channel frequencies) on Feb 17. Small market stations will see a more dramatic increase in power. They simply couldn't afford the power bill to run both the analog and digital station at full power.

New York City and San Francisco represent special cases where reception will get far worse for a few months after Feb 17. NYC has most of the transmitters and antennas atop the Empire State Building and San Francisco has most up on Sutro Tower. When analog is shut down Feb 17, these locations will become construction zones where analog antennas will be removed and new digital antennas installed. To keep from frying the workers, temporary DTV transmitters/antennas will be placed on other sites during construction. Signal quality will be poor during those months. In the case of NYC, new transmitters and antennas are part of the World Trade Center construction project with est. completion in 2012. At that time the Empire State Building reverts to a backup transmitter site.

[freebird73717]

Thanks for the response guys. I live roughly 45 miles from the nearest transmitters. My analog reception is hit and miss. My digital reception is awesome. I get all my stations except ABC. That local hasn't yet started broadcasting in digital.

ou'll have interuped/brakeage in the picture. This will be seen as partial picture and what usually looks to be mpeg pixelation though they are mpeg decoding errors because the signal cannot be completely read and decoded 100 percent. I'm sure there is a better term for this, but the bottom line is you will suffer the same or similar effect of, either no picture or interuped picture. It like the signal is strong and weak, pending how the weather affects the signal.

Thats what I was afraid of. It's not a huge issue but since I live in oklahoma ( where we have some very strong storms ) its was always nice to just tune into analog when the satellite went out.

[usually_quiet]

I guess you will have to keep the weather band radio handy, just in case you loose broadcast TV.

[edDV]

...
Thats what I was afraid of. It's not a huge issue but since I live in oklahoma ( where we have some very strong storms ) its was always nice to just tune into analog when the satellite went out.

At least OK is flat. I've got a ridge between me and the closest stations so I get nothing from them. Next bet is 90 miles the other way and they are using minimum digital power until Feb 17.

Check out this list for detailed plans for your market.
http://www.rabbitears.info/dtr.php

Using Tulsa OK as an example:

The first station KJRH-DT story goes like this

Analog Ch 2 (lower VHF) will be shut down. Current DT channel 56 will relocate to Ch 8 (upper VHF).
Antenna is 1877' and current analog power is 15.9KW.
Antenna is non-directional.
The linked FCC filing shows their plans in detail (see attachment 4).
http://fjallfoss.fcc.gov/cgi-bin/ws.exe/prod/cdbs/forms/prod/cdbsmenu.hts?context=25&a...&fac_num=59439
http://fjallfoss.fcc.gov/prod/cdbs/forms/prod/getattachment_exh.cgi?exhibit_id=630257

This document says current Ch 56 has digital power at 800KW from a temporary antenna and will change to 18.2 KW after the move to Ch 8 on Feb 17. VHF requires less power than upper UHF to go similar distance.

#060 Tulsa, Oklahoma
KJRH DT NBC 02 56 08 1877' 15.9 kW ND 20080219AIE Will reduce TV-02 power 12/01/08, then flash-cut on 02/17/09.
KOET DT PBS 03 31 31 1194' 1000 kW ND 20080716ABN
KOTV DT CBS 06 55 45 1824' 840. kW ND 20080717ABE Will halve DT-55 power 12/08, then flash-cut on 02/17/09.
KTUL DT ABC 08 10 10 1896' 15.0 kW ND 20080214AGS
KOED DT PBS 11 38 11 1709' 35.0 kW ND 20081015AAP Construction complete; will flash-cut 02/17/09.
KDOR DT TBN 17 15 17 1043' 1000 kW DA 20081103ADB TV-17 terminated, will flash-cut ASAP.
KQCW DT CW- 19 -- 20 1633' 1000 kW ND 20080718AQO Will halve TV-19 power 12/08, then flash-cut on 02/17/09.
KOKI DT FOX 23 22 22 1312' 1000 kW ND 20080214AFD
KRSC DT EDU 35 36 36 836.' 144. kW DA 20080717AGG Analog operating at reduced power.
KMYT DT MyN 41 42 42 1250' 900. kW ND 20080214AHI
KTPX DT ION 44 28 28 718.' 1000 kW DA 20080212ADI
KWHB DT REL 47 48 47 1502' 1000 kW DA 20080716AAO Will terminate DT-48 on 02/01/09, then flash-cut on 02/17/09.
KGEB DT REL 53 49 49 597.' 50.0 kW ND 20080926AHL

[Bjs]

My question is that when analog goes dark and the digital switch happens in feb. will my digital antenna suffer the same signal lose that my satellite does when there is a rain storm?

Answer in general for antenna = No

Loss of digital tv signal generally occurs at the transmission tower, so if they glitch, you do as well.

[freebird73717]

edDV thanks for the info. I do get my stations from the Tulsa area. I guess I'll see first hand how the signal will be in a storm seeing as we have a nasty winter storm coming in tonight....

[cal_tony]

I have a comment and two questions about the digital signals and distance.
The comment first.
Digital is all or nothing. Well, in one way yes and in another no. I receive my signals from 40-80 miles away so it is very weather and wind dependent. So the signal has macro blocks in bad weather. Every 5 or 6 min, I'll get maybe 5-10sec. of locked signal and then it's okay again. It's all or nothing but than again, it's watchable. With the wind, since the signals are transmitted from mountain tops is it the transmitting antenna moving around in the wind, is it the branches blowing on the trees near the antenna or is it something else?

Final question about powered antennas. I've bought them in the past and found them to be useful once a good the signal is received by the antenna, but they do nothing about turning an insufficient antenna signal into a good picture. Most are listed as distribution amps. Once they get a good signal they allow you to distribute the picture to all your products without loss. But my understanding is that if the initial cable from the antenna is a short run cable and it doesn't have a good picture, only a better antenna will improve your picture.

Am I missing something?

Tony

[edDV]

edDV thanks for the info. I do get my stations from the Tulsa area. I guess I'll see first hand how the signal will be in a storm seeing as we have a nasty winter storm coming in tonight....

Upper UHF is more susceptible to weather effects than upper VHF. That is probably why the sample NBC station KJRH-DT chose to shift to channel 8 from current 56. The CBS station (currently on 55) using the same tower chose 45 as the final channel. You should see improvement in both come the Feb 17 channel switch.

[edDV]

I have a comment and two questions about the digital signals and distance.
The comment first.
Digital is all or nothing. Well, in one way yes and in another no. I receive my signals from 40-80 miles away so it is very weather and wind dependent. So the signal has macro blocks in bad weather. Every 5 or 6 min, I'll get maybe 5-10sec. of locked signal and then it's okay again. It's all or nothing but than again, it's watchable. With the wind, since the signals are transmitted from mountain tops is it the transmitting antenna moving around in the wind, is it the branches blowing on the trees near the antenna or is it something else?

TV tuners behave somewhat differently to signal fade, multi-path and weather. Early chipsets have more problems than the current 6th generation designs. Tuners use error correction when the signal gets weak. When correction fails, you see pixelation or frame freeze.

There may be some issues with temporary DT transmitting antenna stability. Final installations should be stable. More likely the problem is with trees or weather interference along the direct line of sight path.

Final question about powered antennas. I've bought them in the past and found them to be useful once a good the signal is received by the antenna, but they do nothing about turning an insufficient antenna signal into a good picture. Most are listed as distribution amps. Once they get a good signal they allow you to distribute the picture to all your products without loss. But my understanding is that if the initial cable from the antenna is a short run cable and it doesn't have a good picture, only a better antenna will improve your picture.

Am I missing something?

Tony

The story is quite different for inside vs large directional roof top antennas (deep fringe reception). Preamplifiers for the latter mount up on the antenna mast to avoid cable losses and are fed power from inside the house up the cable.



Distribution amps are a different beast and do little to improve reception. They mount in the house and function as powered splitters (no gain loss).


http://en.wikipedia.org/wiki/ATSC_tuner
http://en.wikipedia.org/wiki/8VSB

[vhelp]

TV tuners behave somewhat differently to signal fade, multi-path and weather. Early chipsets have more problems than the current 6th generation designs. Tuners use error correction when the signal gets weak. When correction fails, you see pixelation or frame freeze.

Funny you should bring that up. Coencidentally, when I was shopping (browsing) around in BestBuy, I was watching some of the lower price HDTV--15" to 22" wide--for under $300, and lowest was $199, I think. Anyway. They were connected via Coax (OTA, I believe) and sharing some distribution box I would assume, since all the other tvs in that area (about 30 or so) were receiving the same broadcast, which was one of their home-brews advert-ing their before/after Analog vs. Digital picture hype) and while watching the lower price (they caught my eye) I couldn't help notice that the receiption was bad, and the picture kept breaking up or pixelating, etc--the usual. And this was on account of (you guess-ed it) a rain storm in my area. Anyway. On one of the units, (was marked $229 I believe) it was the only one not suffering the picture brakeup. It was clean and playing smoothly while the other in the same row was breaking up constantly.

The point I was trying to make here, was the at that hdtv had caught my curiosity that I almost wanted to get it, because it was way outperforming all the other tvs in that lineup and then some, from the other isles. I was taken from that experience. So, I kept in the back of my mind how much I wonder what exactly was the element in that tuner that kept it *keeping* a clean and underdisturbed picture. I should have payed more attention to the observation and expanded my comparison to the other tvs on the floor. But I was in a hurry in search of other gadgets and things. I was xmas shopping for our dept's grab-bag party this week.

Still, I realize that this picture brakeage issue is dependant on the tv: machanics, craftmenship, brand, and so on, but this set definately was not your tipicle pricy one!! That was the shocker. I'll have to make another pass at that isle the next time I brows bestbuy. I'm curious.

...

Preamplifiers for the latter mount up on the antenna mast to avoid cable losses and are fed power from inside the house up the

On another note. I wonder if that Preamp would do any good for my antenna (see below) that I have in my bedroom. If you recall, its an outdoor roof antenna I rigged up on empty boxes in my bedroom, near a window. Also, I came to the final observation that my stand-alone tv tuner receiver (see below) receives weak signal far greater than any of my computer's HD tuner cards. There is actually a big diffference in picture strength on this unit when reviewing the strength meters of each device.

** Antenna: Radio Shack brand, VU-75XR VHS/UHF/FM
** The pie chart states, GREEN and 75 mile range
** Pro Brand, Digital Stream HD3150Plus DTV receiver

All these things effect picture quality, in terms of how consistantly strong a picture you recieve without interuption or breakage, and how many channels your unit can receive -- lots of variables, etc., etc., etc.

-vhelp 4963

:P *~*!*~*!~* HaPpY HoLiDaY *~*!*~*!~*

[edDV]

In the early days most stores connected HDTVs to the normal NTSC coax feed and the picture was usually awful. Then the better stores installed YPbPr distribution to each HDTV fed either by a sat channel, Disc device or Blu-Ray player through a DA.

Most early HDTV sets lacked an ATSC tuner. They all have one now. Today the stores feed either YPbPr or distributed RF from a roof antenna. If the latter you are getting a comparison of tuner performance. Best to shop during bad storms.

A Weingard or Channel Master Preamp may help your directional VU-75XR. You can always return it. That antenna preformed well in this test for VHF but not so well for UHF.
http://www.hdtvexpert.com/pages/antout.htm