"Alan F" <afiggatt1@[EMAIL PROTECTED]
> wrote in message
news:yxOUj.8817$0L.7202@[EMAIL PROTECTED]
> Daniel W. Rouse Jr. wrote:
> > This concerns OTA DTV audio dropouts, will this problem eventually get
> > fixed?
> >
> > Currently, it seems that if the picture develops more than just a
small
> > amount of artifacts, even if the picture is still in motion and is
still
> > mostly discernable, the audio immediately drops out once the artifacts
start
> > to appear. (In that respect, analog broadcast seems much more robust
in
the
> > audio aspect of the picture, in that even a snowy analog picture that
was
> > still able to broadcast in color retained its audio, albeit with
audible
> > noise within the audio.)
> >
> > My own expectations are that the audio should only drop out when the
picture
> > actually freezes, before it recovers or when No Signal gets displayed.
> > Digital TV is supposed to be better picture (which it is, when a
situation
> > that causes the display artifacts doesn't occur) and better sound
(Dolby
> > Digital up to 5.1 channels) but I am also expecting better reliability
> > (i.e., less signal drift and less audio loss).
> >
> > Further discussion is welcome.
>
> You need more gain on the antenna setup. Glitches in the station
> transmission do occur, but for me, audio and/or picture dropouts are
> pretty infrequent. If you are getting frequent dropouts, you either have
> a marginal signal or multi-path problems. A newer generation ATSC tuner
> can improve the reception reliability for multi-path and marginal
> signals, but you have not stated anything about your setup.
>
My additional testing shows that it's probably a marginal signal issue and
also has to do with the room the TV is in. At best, checking the signal
indicators is showing about 75% signal strength and when the audio
dropouts
occur it looks like the signal strength is falling all the way in to the
30
to 40% range.
In that room, neither the TERK TV-5 nor an RCA ANT-401 nor an RCA ANT-200B
antenna can seem to hold a stable picture for more than 30 minutes maximum
before some sort of video corruption occurs, which results in the audio
dropouts. I have managed to find an RCA-200B antenna position which will
hold a stable picture for up to 2 hours. Althought antenna position loses
two channels (15-1 and 15-2), I'll continue to use that antenna position
for
now (I rarely ever watch programming on channel 15 in analog, and I'll
probably not watch programming on the digital equivalents 15-1 and 15-2.)
I
probably still need to find a better indoor amplified antenna for use in
that problem room
But, in another room with another TV, the TERK TV-5 performs almost
flawlessly. In that other room, though, that TV is closer to a window. I
don't need to change a thing for that other room, since the only way I get
errors is if I am standing almost right next to the antenna.
The amplification level of the TERK TV-5 is 40 dB maximum. The
amplification
level of the RCA ANT-401 is 15 dB maximum. The amplification level of the
RCA ANT-200B is not known as I no longer have the box or the manual for
that
antenna (though the antenna itself still works). These are all indoor
antennas, because outdoor antenna usage is not an option unless it is a
free-standing dish type antenna (apartment complex rules).
It should also be mentioned, however, that in both rooms neither TV with
any
antenna gets VHF reception over analog, even though all the antennas have
VHF and UHF signal receiving elements. As such, all of the stations
received
over analog are UHF only (15, 39, 51, 69), and with the digital reception,
all of the stations received so far are the digital equivalents of the
analog UHF stations (15-1, 15-2, 39-1, 39-2, 51-1, 69-1).
> A 3rd possible cause for dropouts is co- or adjacent channel
> interference. A number of analog <-> digital interference issues will be
> resolved next February 18, 2009 when the remaining subset of 1800 full
> service stations turn off their analog signals. But this would likely be
> a problem for a specific channels, not all of them, which your post
> implies. But there will be no magic improvement next year, except for
> the stations that will be providing a stronger digital signal.
>
Stations providing a stronger signal might help. I suppose what I need to
do
at this point, for the problem room, is to either place another amplifier
before the antenna or find another amplified antenna with a gain of more
than 40 dB.
Again, though, outdoor antenna usage is not an option, or I would have
already done that as the first thing for digital reception.
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