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

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nbound-au

The Graveyard Shift
#24
ATSC isnt unstable. ATSC will provide a better picture than NTSC in equivalent conditions.

Only once it reaches a point, the error correction capabilities of the format can no longer cope, and that is when you lose the signal. At that same point the NTSC equivalent image would be rather snowy, and/or distorted (sure probably watchable, but pretty poor in comparison to a good image).

Its better to think of ATSC being hhighly resilient, to the point where it is overcome by overwhelming force.

Yes ATSC has its pitfalls, DVB-T and ISDB-T do too. And some may be better than other in other respects. But none of them are unstable transmission formats.


If your personal antenna system is often knocked out by the slightest signal interruption, then your antenna system is at fault, perhaps consider a professional with metering equipment who can factor in signal fluctuations and other factors.


Finally, regardless of any of the above, giving a signal more power can create more problems then it may fix.
 
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#25
Unfortunately airplane flutter is much more of an issue with ATSC than NTSC & really no real remedy other than moving. (I live right next to Dulles Intl Airport-ouch)

Yes, it was noticable with NTSC, but it didn't cause the picture to freeze or tile. Too bad a buffering system isn't built into tuners similar to what was used in the portable CD & minidisc players which virtually eliminated digital interruptions.
 
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#26
At that same point the NTSC equivalent image would be rather snowy, and/or distorted (sure probably watchable, but pretty poor in comparison to a good image).
I'd rather the image be poor and watchable than "good" and unwatchable. An unwatchable signal is not good.

In SD, NTSC does have better color rendering than ATSC.
 

nbound-au

The Graveyard Shift
#27
I'd rather the image be poor and watchable than "good" and unwatchable. An unwatchable signal is not good.
Then you need to upgrade your antenna system, its not the broadcasters fault that your antenna system isnt powerful enough to receive whichever station is required.

In SD, NTSC does have better color rendering than ATSC.
NTSC was actually called Never The Same Colour within industry as a running joke, and it was for good reason.
 

nbound-au

The Graveyard Shift
#28
Unfortunately airplane flutter is much more of an issue with ATSC than NTSC & really no real remedy other than moving. (I live right next to Dulles Intl Airport-ouch)

Yes, it was noticable with NTSC, but it didn't cause the picture to freeze or tile. Too bad a buffering system isn't built into tuners similar to what was used in the portable CD & minidisc players which virtually eliminated digital interruptions.
A buffering system would not help as when a skip occurs on a discman for example, the finds where it was when the skip occured before the buffer runs out and plays from there (while reading ahead to refill the buffer).

TV signal on the other hand is a constant stream, if you miss something, there is no way to have that information presented to your TV's tuner again.


Airplane flutter is one of those annoying things, especially if the location is really bad. there are of course thing you can attempt to stop it or at least reduce the severity though.

It may cause more of an issue with ATSC as its multipath handling is poorer than DVB, but I can only speculate.
 
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nbound-au

The Graveyard Shift
#30
Heirachical modulation could help*, but i dont think ATSC allows for it. DVB-T does but nowhere I am aware of actually uses it anyway. I dont know how well that idea would work in real life though


*If high bitrate signal fails, tuner could then instead decode the low bitrate superimposed signal.
 

Fringe Reception

Super Moderator, Chief Content Editor
Staff member
#31
I'd rather the image be poor and watchable than "good" and unwatchable. An unwatchable signal is not good.

In SD, NTSC does have better color rendering than ATSC.
Chris,

I for one, would never want to return to narrow-screen fuzzy analog signal reception. I prefer crystal clear wide screen HDTV.

If you have undependable reception, its not the fault of 8VSB its because your antenna system isn't doing the job. The colors offered by ATSC are absolute and can be 'dialed-in' much easier than analog colors and as posted above, where they were never consistant from channel to channel or even program to program.

Jim

Analog VS Digital on the same TV:



 
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#32
It is more complicated than that. The fact that DTV would give a clearer picture is not the only issue. The fact is government officials made a decision that caused so many people to lose so much access and they couldn't care less. I lost 3 of my 5 main channels and upgrading to a more high performance UHF antenna only brought back in one of those 3 lost channels; and even still it's reception is not very reliable. The re-mapping of formerly vhf analog channels to UHF digital is apparently another aspect of the problem. Those of us at the fringe and without LOS could still get good solid VHF reception, but those vhf channels that got re-mapped to uhf all of a sudden became blocked. All 3 that I lost were vhf that got re-mapped to uhf. The 2 of the 5 that I continued to receive very well remained VHF, (analog vhf became digital vhf). My opinion, FWIW.
 

Fringe Reception

Super Moderator, Chief Content Editor
Staff member
#33
okie_flats,

Please remind us with your TVFOOL antenna survey and current antenna setup.

I lost KVOS-12 (now 35) and I had to build my own antenna to reestablish it.

Jim
 
#34
It's my antennas fault? My antenna worked better before the switch than after. So, it isn't my antenna.

No, I'd rather have a fuzzy signal (not that they ever were) than no picture or one that breaks up into blocks.

I am perfectly happy with SD. Really, the only reason I would buy an HDTV is for Blu Ray.

You really have to think about people who live in apartment buildings. I don't live in an apartment, but some people do. They can't put an external antenna on their building.
 

Fringe Reception

Super Moderator, Chief Content Editor
Staff member
#35
Chris,

'My antenna worked better ..." BS ... since you received distorted signals in the analog days admit it - it was crap.

Wake up! FREE OTA is digital now and analog is long gone. Stop it: no more whining here.

We need your antenna survey to try to help you.

Jim
 

nbound-au

The Graveyard Shift
#37
It's my antennas fault? My antenna worked better before the switch than after. So, it isn't my antenna.
Even if you got a crystal clear analog image (which not many people did!), your system could have easily deteriorated since.

The amount of times Ive heard similar stories from people, then I go around, fix it up, and they are just WOW, and their opinion completely changes.

If your reception drops out in bad weather, wind, at certain times of day/year, then it probably is either faulty, or wasnt installed to the correct standards to begin with. If the latter, that not necessarily your fault, it can be hard to install reliable digital systems without a meter to let you know the signal is in spec, and their is enough of a buffer to allow for signal strength/quality fluctuations.

And TBH a meter is invaluable for tricky installations, when I walk into a home, and plug in my meter I can usually just say something like: "Your not getting X, Y only works occasionally, the others look fine, though Z could be an issue in future" and be dead on or not far off, before Ive asked them to explain to me the problem they are having.



No, I'd rather have a fuzzy signal (not that they ever were) than no picture or one that breaks up into blocks.
Shall we lose all our subchannels and HD programming? I think I'll stay with digital!

You really have to think about people who live in apartment buildings. I don't live in an apartment, but some people do. They can't put an external antenna on their building.
Only the landlord or body corporate is stopping them. Get them to change their minds and you are set!

All apartment complexes here (with very few exceptions) have MATV systems, or individual antennas [for smaller complexes].
 

nbound-au

The Graveyard Shift
#38
Actually it did. There was no snow and minimal ghosting.
Ghosting is the same as multipathing (its how multipathing appears on an analog system), and to a certain level with ATSC you can have that, and see no effect on the picture, once it hits a point it then becomes too much and the signal intregity is affected. The level of ghosting required to disrupt an ATSC system, all else being equal, is more than "minimal" ghosting, otherwise digital TV would have went the way of the Dodo, as ghosting was not uncommon in the analog era.

Snow thats visible by most, is one of the last things to appear (because at that time its becoming harder to discern the signal from background noise)
 
#39
Shall we lose all our subchannels and HD programming? I think I'll stay with digital!
HD started out in analog. I got more channels with analog than with digital.

Only the landlord or body corporate is stopping them. Get them to change their minds and you are set!
The problem is a structural one not a political one.

All apartment complexes here (with very few exceptions) have MATV systems, or individual antennas [for smaller complexes].
With many runs to each apartment. Each split weakens the signal.

When I say I got minimal ghosting, I meant it sometimes didn't happen.
 
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nbound-au

The Graveyard Shift
#40
With many runs to each apartment. Each split weakens the signal.
These arent passive systems, unless you are in a good area. There is appropriate amplification. These are extremely reliable systems.

When I say I got minimal ghosting, I meant it sometimes didn't happen.
And that may be, but it means little for whats currently wrong for your digital system.

When youve got several regular posters telling you something, some of them even involved in doing it professionally, chances are, they are on to something.
 
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