Attention TV Viewers: DTV signals are weaker than analog signals...

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scandiskwindows9x

Moderator of DTV Latino
#81
But DVB T can't work on 29.97fps or in 6MHZ bands for work in American authorized bands need adaptations even Columbia with their DVB adapted don't know how would work in our American tunneling or even with our frame rate also, if were for that then better uses ISDB-T which is for 6mhz band and the Japanese market were in NTSC , also is more robust to multipath than DVB BY the interleaver which randomize the error by four parts.

Enviado desde mi XT615 usando Tapatalk 2
 
#82
If analog tv takes up more bandwidth? Why wouldn't you use it for HD? HD signals take up more bandwidth than SD. This is why streaming HD over the internet is slower than streaming SD.
 

nbound-au

The Graveyard Shift
#83
But DVB T can't work on 29.97fps or in 6MHZ bands for work in American authorized bands need adaptations even Columbia with their DVB adapted don't know how would work in our American tunneling or even with our frame rate also
Wrong, DVB-T works with 6Mhz (Ex-NTSC nations VHF/UHF), 7Mhz (Australian VHF/UHF, European VHF), and 8Mhz (European UHF) bandwidths. Colombia did not have to modify DVB-T, as it was created with 6Mhz channelling in mind.
www.dvb.org/technology/fact_sheets/DVB-T_Factsheet.pdf

Colombia has actually recently decided to upgrade to DVB-T2 aswell :)

It is also compatible with both 50 and 60 Hz frame rates (29.97 or 30 Hz would just be progessive scan and also supported).

There is no reason why ex-NTSC nations cannot use DVB-T. Some others include Taiwan and Burma.



if were for that then better uses ISDB-T which is for 6mhz band and the Japanese market were in NTSC , also is more robust to multipath than DVB BY the interleaver which randomize the error by four parts.
All digital systems have an interleaver.

ISDB - Wikipedia, the free encyclopedia - Comparative Table

For the most part ISDB-T and DVB-T are pretty similar as far as transmission specs go, its just the formatting of the signal and desired result that is radically different.

The major benefit I can see from ISDB-T is 1seg capability, the additional selectable time interleaver isnt going to make too much difference overall.
 
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nbound-au

The Graveyard Shift
#84
If analog tv takes up more bandwidth? Why wouldn't you use it for HD? HD signals take up more bandwidth than SD. This is why streaming HD over the internet is slower than streaming SD.
Analog Tv takes up the same bandwidth as a single DTV station. So where you could previously fit a single NTSC/PAL broadcast, you can now fit a 1080i HD Primary channel, and several 480/576i SD subchannels.

So lets imagine theres a fake station called "KRAP", tee hee hee...
KRAP analog is 6Mhz in bandwidth and contains a single 480i NTSC broadcast.

KRAP upgrades to digital...

KRAP is still 6Mhz, and they upgrade their original channel to 1080i HD, they then add some 480i SD subchannels for extra content.

Same size, more stuff! :)
 

scandiskwindows9x

Moderator of DTV Latino
#85
Wrong, DVB-T works with 6Mhz (Ex-NTSC nations VHF/UHF), 7Mhz (Australian VHF/UHF, European VHF), and 8Mhz (European UHF) bandwidths. Colombia did not have to modify DVB-T, as it was created with 6Mhz channelling in mind.

wrong the DVB-T system was not created for 6MHZ tunneling just for europeans ones of 7-8MHZ you are who are wrong, the fact that you get your money installing antennas do not make be wiser in technical things.

i can tell that is not for 6MHZ bands because i was when was undecided in the system adoption, all claimed that do not wanted DVB and also the technical analisys and field test just give as conclusion that DVB-T just can give SD images over 6 MHZ in HD can not offer in the 6MHZ bands and needs special techniques or broadcasts in MPEG 4 codec, also in performance in geography as where i live do not offer anything new, and in comparison with ATSC have not a lot of advantage and just in resistance to multipath have some advantage DVB-T .

Also have the technical documents that proofs what i am saying also. made by many test done in Santiago .


www.dvb.org/technology/fact_sheets/DVB-T_Factsheet.pdf

Colombia has actually recently decided to upgrade to DVB-T2 aswell :)

It is also compatible with both 50 and 60 Hz frame rates (29.97 or 30 Hz would just be progessive scan and also supported).

There is no reason why ex-NTSC nations cannot use DVB-T. Some others include Taiwan and Burma.




All digital systems have an interleaver.

ISDB - Wikipedia, the free encyclopedia - Comparative Table

For the most part ISDB-T and DVB-T are pretty similar as far as transmission specs go, its just the formatting of the signal and desired result that is radically different.

The major benefit I can see from ISDB-T is 1seg capability, the additional selectable time interleaver isnt going to make too much difference overall.

the TI makes more robust the broadcasts against the multipath generated by vehicles and other external conditions please

DiBEG | Time Interleave

read this,


by the way the advantage in power to broadcast in urban environments is false, in fact a channel that uses 200KW can not be received with indoor antenna and with rooftop ones the signal of 200kw just is poor to reach my place.

Also i do not have an idea or clue why yiou defend an system if you have to go to the ridiculous amount of an antenna of 80 elements to pick up signals in HD i do not know if you have stocks in the DVB organization or what so i do not even understand why defend a system which was in here tested that can not offer HD in 6 MHZ band and was alike ATSC in performancein urban environments.
 
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scandiskwindows9x

Moderator of DTV Latino
#86
Analog Tv takes up the same bandwidth as a single DTV station. So where you could previously fit a single NTSC/PAL broadcast, you can now fit a 1080i HD Primary channel, and several 480/576i SD subchannels.

So lets imagine theres a fake station called "KRAP", tee hee hee...
KRAP analog is 6Mhz in bandwidth and contains a single 480i NTSC broadcast.

KRAP upgrades to digital...

KRAP is still 6Mhz, and they upgrade their original channel to 1080i HD, they then add some 480i SD subchannels for extra content.

Same size, more stuff! :)
in Chile a Tv channel the Chilevision HD have two HD channels over digital both in MPEG 4 and 1 one second for mobile cell phones and others in low resolution and low specifications.

the difference is

in Analogic just fits one TV channel and the service quality and service experience to consumer was sometimes bad

in digital can fits many channels in one frequency or just one in HIGHEST QUALITY or many in good quality and the service experience would be good to consumers since the signal is more resistent to fading or degradation in some cases and with rooftops antennas can get the images clean versus analogic that get ghosty images or with rain ones.
 

nbound-au

The Graveyard Shift
#87
the TI makes more robust the broadcasts against the multipath generated by vehicles and other external conditions please
Time interleaving is only effective for mobile reception, for stationatry use it has little effect. Impulse noise isnt a big problem for DVB-T either (at VHF-High or UHF frequencies)

Also i do not have an idea or clue why yiou defend an system if you have to go to the ridiculous amount of an antenna of 80 elements to pick up signals in HD i do not know if you have stocks in the DVB organization or what so i do not even understand why defend a system which was in here tested that can not offer HD in 6 MHZ band and was alike ATSC in performancein urban environments.
Hardly anyone needs an 80+element antenna!? Maybe if you have a 2edge signal, or you are 60+miles (100+km) away from the transmitter!

The DVB organisation is a not-for-profit consortium... But regardless, Im a tradesman who works for money and do not have any stocks or shares in any companies.

Taiwan operates the HD channel "HiHD" just fine in a 6Mhz channel.

DVB-T has better performance in urban environments than ATSC. ATSC is on the other hand, more efficient in rural environments (less power required). This is in part why it was chosen.
 

scandiskwindows9x

Moderator of DTV Latino
#88
Time interleaving is only effective for mobile reception, for stationatry use it has little effect. Impulse noise isnt a big problem for DVB-T either (at VHF-High or UHF frequencies)





DVB-T has better performance in urban environments than ATSC. ATSC is on the other hand, more efficient in rural environments (less power required). This is in part why it was chosen.
now in some regions of the south of Chile are noticing that the ISDB-T broadcasts have not a good coverage and there is mstly rural and a place that is urban so now are noticing the mistake that our government did as always thinks in Santiago but never in the rest of the country, also Santiago some towns are like rural not a lot of taller buildings and not an intense traffic
 

nbound-au

The Graveyard Shift
#89
now in some regions of the south of Chile are noticing that the ISDB-T broadcasts have not a good coverage and there is mstly rural and a place that is urban so now are noticing the mistake that our government did as always thinks in Santiago but never in the rest of the country, also Santiago some towns are like rural not a lot of taller buildings and not an intense traffic
If that turns out to be a big problem, then hopefully your telecommunications authority will allow a suitable increase in ERP for the affected areas :)
 

scandiskwindows9x

Moderator of DTV Latino
#90
If that turns out to be a big problem, then hopefully your telecommunications authority will allow a suitable increase in ERP for the affected areas :)
yeah in fact just now are studying the real propagation of the DTV system on air, i think is not criteria must be done before that of choose a system those studies and not now, in the city of concepción noticed in areas with dense forest and between is houses very far away of the city can not pick up any digital signal. then blame to the centennial forests that are there.
 
#91
Actually I'm going to have to agree with EVERYONE....BUT ( and yes the word BUT cancels everything u say before it( BUT....I'd have to go with....the basic idea that what was missing STILL is COVERAGE like always....I'm sure if u look at the big picture most TV stations RANGE aren't any more much improved than what they we're previously ....
 

nbound-au

The Graveyard Shift
#92
Actually I'm going to have to agree with EVERYONE....BUT ( and yes the word BUT cancels everything u say before it( BUT....I'd have to go with....the basic idea that what was missing STILL is COVERAGE like always....I'm sure if u look at the big picture most TV stations RANGE aren't any more much improved than what they we're previously ....
That not the stations or digital's fault, the FCC limits the ERP of each station to prevent things like co-channeling problems, and to stop stations broadcasting to markets they arent allowed to broadcast to.
 
U

uncle mike

Guest
#93
lack of transmission power from digital towers.

DTV is not awful. The transmission quality is poor.
 
L

Larry Boydston.

Guest
#95
You guys have gotten awfully wound up with very complicated research and "information" concerning the reception of television signals. You sure do rely on TV Fool a lot. I've been to their website and was overwhelmed by the complex information presented there. After studying the information presented there, and the subsequent information that I had already gleaned from hours of basic Internet searches, concerning the problems that I am having with "antenna tv", I came away with the conclusion that I may never receive "antenna tv" without huge quality issues remaining.

It boils down to this. You shouldn't have to be a "rocket scientist" in order to receive a decent quality tv signal. You shouldn't have to be one, to get a fairly reliable signal either. In the "old days", right here in the same location we were able to get color tv that was of decent quality and was reliable unless our area was having severe weather. Yes, we didn't have as many stations, but the ones we had then (ABC, CBS, NBC, and 2 local UHF channels) were received good enough. Now, with Channel Master's best set-up for my area I still have my problems, although better than I had with an indoor amplified antenna, or a 5 star rated(on a dozen review websites) Chinese outdoor antenna which I amplified with a Winegard 20 db gain,1 db noise figure amplifier. The information I got on the Channel Master website was much the same as I was able to get from the TV Fool site.

I was able to converse with a representative in almost real time about my problems and possible solutions. He did not pressure me to buy anything from Chanel Master, and informed me from the very beginning that my problems could be caused from many things, including cell phone tower interference(there are 144 of them due north of my location, between me and where all of my stations are broadcast from), whether I live on a hill or in a valley(I live on a hill). and whether I have any existing structures that could interfere with reception( I do not). There is also the possibility that my homes electrical wiring could influence my reception (I SURE HOPE NOT !). I chose, on my own, to buy Channel Masters best solution to my problems. It cost me about $160.00, and has a no questions asked money back guarantee. It's also made in the U.S. I have presented the information here, not hoping for a solution, but just in curiosity about the many replies I may receive here about my post. I think that most will refer me to TV Fool, but I have already studied the info there until my eyes crossed, with no obvious solutions presented, nor did any info presented point me in a direction that led me TO a solution.

In my area we only have recourse to one "cable" provider, Suddenlink. We had them for about 2 years. During that time we had good quality, reliable reception........about 50% of the time. The other 50% of the time, we had NO SIGNAL. They had lousy tech service and even worse customer service. It was a nightmare cancelling our contract. This started my "adventure" into antenna tv. All I now no for sure is this. In the "old days" we got good reception with reliable service most of the time with the old analog signals. My dad would once in a while turn the antenna to get a little better reception. You didn't even have to use co-ax cable. Electronics components back them were generally archaic compared to modern components, yet we watched tv a lot, with few problems. If my dad would have had to jumped through the hoops that I have, in order to watch tv, we would have never watched tv.

The whole thing appears to be a simple coin toss now. If you get good reception, consider yourself blessed. If you are in my position, you either give up or you keep on trying as I will. I don't know what I will try next, but I won't repeat what I have already tried that didn't work. That includes further research of the TV Fool website, the Channel Master website, or even the FCC website( it's a bad joke, and they won't answer my emails),. I'll just keep on experimenting I guess.

If anybody replies to my lengthy post, I thank you for doing so. I'll read all replies, but I won't post further comments. Thanks to all jor the info posted here, and good luck to all who have problems with tv reception (you'll need it).

Larry B.
 
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