| Author |
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inkyblacks@yahoo.com
Guest
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 Posted:
Fri Apr 01, 2005 8:28 am Post subject:
Re: DTV reception is much more difficult than analog |
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Bob,
Nice pictures Bob!
Alan,
You need to call your mother and ask her to give you a lesson in
manners.
IB
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Bob Miller
Guest
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| Posted:
Fri Apr 01, 2005 8:28 am Post subject:
Re: DTV reception is much more difficult than analog |
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Alan wrote:
| Quote: | In article <GM33e.77$N13.66@newsread3.news.pas.earthlink.net> Bob Miller <robmx@earthlink.net> writes:
Alan wrote:
No, they wouldn't. If the signal is not present in a spot, it does't matter what receiver you use.
Dead spots in the room are rare with COFDM. Maybe because with COFDM in a room you would use an omni antenna where with 8-VSB to avoid the
multipath problem with to many signals bouncing around that room you would use a directional antenna.
No, this is nonsense. The symbol rate of 8vsb is not that high. Multipath within the room will not be an issue for intersymbol interference.
The fact is that with 8-VSB with indoor directional antennas it is easy |
to kill reception in a room by simply walking around or by a person
simply taking a particular position. If the signal interference creates
nulls that 8-VSB can't handle or if it is simply multipath that fact
remains that COFDM does not have this problem at the same power levels
or even much lower in our experience.
| Quote: |
The omni with COFDM welcomes the multipath signal no matter where it is bouncing from and is capable of adding these signals together for a
stronger signal whereas the directional with 8-VSB is trying to specifically avoid these other signals and just concentrate on the main
or strongest signal.
The problem, twit, is that the signals also CANCEL when they combine with the strong reflections indoors. When the signals CANCEL, it doesn't matter
if you are using 8VSB, COFDM, NTSC, or something else. No signal is no signal.
Is your only argument name calling? Signals cancel and no signal is no |
signal, understood. But COFDM working in a room with an omni antenna
where 8-VSB fails using a directional antenna while the 8-VSB signal is
coming from a near transmitter at 800,000 Watts and COFDM is coming from
a far antenna with 1000 Watts indicates that COFDM does not seem to
suffer from the number of nulls you suggest affect 8-VSB. Since there
should be the same number of nulls for both signals the facts that I
know suggest that it is NOT nulls but multipath that is killing 8-VSB
even with 5th gen prototype LG receiver this was true. It could not hold
a candle to a 1999 COFDM receiver for indoor reception.
| Quote: |
So don't blame to much on dead spots, it may be the directional antenna that is not aimed at all the signals at once.
As for indoor aerials (antennas) with the U.K. Freeview system:
http://www.freeview.co.uk/faqs/aerialsandreception.html
I quote from there:
A small number of households may be able to use a set top aerial. This only applies if you live in a coverage area close to a
transmitter, but reception would still be unreliable and so we strongly recommend that you use a roof or loft aerial for good
reception.
So, the folks who use COFDM say it doesn't have this magical ability to work with indoor antennas.
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The folks who are using the 2K version of COFDM in the UK at average
power levels of 3.7 kW are saying this. BTW some folks in the UK under
these remarkable conditions are reporting perfect reception with indoor
antennas at 25 miles of these obscenely low transmitter powers.
And then there is the reality that in the UK using these absurd low
power levels 500,000 receivers will be purchased in April. They probably
work pretty good with just about any kind of antenna as reported by
friends there.
Bob Miller
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Bob Miller
Guest
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| Posted:
Fri Apr 01, 2005 8:28 am Post subject:
Re: DTV reception is much more difficult than analog |
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inkyblacks@yahoo.com wrote:
| Quote: | Bob,
Nice pictures Bob!
Alan,
You need to call your mother and ask her to give you a lesson in
manners.
IB
The gentleman called Richard in the photos is Richard Bogner of Bogner |
antenna fame. He built about 50% of the antennas broadcasters used over
the years AFAIK. Built antennas for the Apollo manned missions to the
Moon and was involved in the antennas that were used in the early
warning DEW line across northern Canada. He is the one holding the
winning loop antenna. A COFDM convert who had been in the TV antenna
business since day one.
Meric Adriansen in the photos worked for ABC testing COFDM for a number
of years. ABC was a big fan of COFDM before the Congressional
intimidation games.
Bob Miller |
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Jeff Rife
Guest
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| Posted:
Fri Apr 01, 2005 9:17 pm Post subject:
Re: DTV reception is much more difficult than analog |
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inkyblacks@yahoo.com (inkyblacks@yahoo.com) wrote in alt.tv.tech.hdtv:
| Quote: | It is often not a black and white issue of signal or no signal. The LG
5th chip receiver claims to be able to display signals at one fourth
the signal strength of previous designs.
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That claim is bogus. Raw signal strength has little effect on reception
of digital TV signals. The important number is carrier-to-noise
ratio (C/N). As long as it is above the 19dB threshold required for ATSC,
you get a picture. If it is less, you don't get a picture. Dropouts are
caused by the signal moving above and below the threshold.
I can remove my pre-amp (26dB) and add a 12dB attenuator and still receive
every station I get now. That's 38dB of raw signal strength attenuation,
but the C/N change is only about 3-6dB for me. Since all of my stations
are at least 22dB (and some as high as 30dB) C/N right now, I don't lose
the picture on any of them.
But, you want as much headroom as possible on C/N, so I use the pre-amp.
The problem with an indoor antenna is that there can easily be 50-70dB
of attenuation on the raw signal, and that will likely result in a drop
of C/N of 10-15dB. Theoretical maximum headroom on C/N for ATSC is
something like 20dB, and it is very difficult to achieve that (if you are
close enough to the antenna to get a lot of raw signal, you run into
problems with the design of the receiver and end up with overload, which
lowers C/N). My 11dB headroom on a couple of channels is in the "awesome"
category.
To put some of this in perspective, NTSC requires about 45dB C/N to achieve
a quality picture, and getting more than 10dB of headroom is virtually
impossible. Typicaly headroom on C/N for FM radio is less than 6dB.
--
Jeff Rife |
| http://www.nabs.net/Cartoons/RhymesWithOrange/MailerDaemon.gif |
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Mike Rush
Guest
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| Posted:
Thu Apr 14, 2005 6:02 pm Post subject:
Re: ATSC Mandate News |
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"The Consumer Electronics Association has proposed all sets 25 inches and
larger have the digital receivers by March 2006 instead and eliminate the
2005 interim step. The FCC has sought comment on the proposal."
Wait a minute . . . CEA members are the ones that manufacture the TV's. If
they want digital tuners in the sets sooner, all they have to do is put them
in. What does the FCC have to do with it?
"K. B." <hotmail.com@lis2lis2> wrote in message
news:h9nr51linm8u1a7d5lsaa9pc5rsahulbq7@4ax.com...
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Jeff Rife
Guest
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| Posted:
Thu Apr 14, 2005 9:20 pm Post subject:
Re: ATSC Mandate News |
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Mike Rush (miker@avenuenospamcable.com) wrote in alt.video.digital-tv:
| Quote: | "The Consumer Electronics Association has proposed all sets 25 inches and
larger have the digital receivers by March 2006 instead and eliminate the
2005 interim step. The FCC has sought comment on the proposal."
Wait a minute . . . CEA members are the ones that manufacture the TV's. If
they want digital tuners in the sets sooner, all they have to do is put them
in. What does the FCC have to do with it?
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They don't want it *sooner*...they want it later.
The current requirement is that at least 50% of television sets with
screens of 25 inches to 35 inches by July 2005 and 100% of the same
sets by July 2006.
The CEA wants 0% by July 2005 and 100% by July 2006. This allows them
another year to screw around and then try to get the deadline extended
*again*.
The advantage to the CEA in extending the deadline is that about 50% of
sets sold today without an ATSC tuner will either have to be replaced
or have an STB added. This means another sale for some CEA member
company.
--
Jeff Rife |
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GMAN
Guest
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| Posted:
Mon Apr 18, 2005 8:05 am Post subject:
Re: ATSC Mandate News |
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In article <cP-dnUPyV8XaLcPfRVn-jw@wavecable.com>, "Mike Rush" <miker@avenuenospamcable.com> wrote:
| Quote: | "The Consumer Electronics Association has proposed all sets 25 inches and
larger have the digital receivers by March 2006 instead and eliminate the
2005 interim step. The FCC has sought comment on the proposal."
Wait a minute . . . CEA members are the ones that manufacture the TV's. If
they want digital tuners in the sets sooner, all they have to do is put them
in. What does the FCC have to do with it?
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Because the FCC has to approve the move if it changes a set mandate. Even if
it is a benefit to the whole transition period, it still needs the rubber
stamp of approval.
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loz
Guest
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| Posted:
Mon Aug 22, 2005 10:49 pm Post subject:
Re: Sky reveals HDTV launch lineup |
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"John Russell" <john_e_russell@hotmail.com> wrote in message
news:430a54f1$1_2@mk-nntp-2.news.uk.tiscali.com...
| Quote: | Most of my relatives/freinds have no interest in the internet, or digital
TV. They don't have large TV's either. I'm part of the "grey market" you
see, that vast majority who get ignored.
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I noticed you ignored my earlier post about my 75 year old mom going out and
buying, and mastering, a freeview box, and now looking for a LCD TV.
Just because you and your relatives/freinds have no interest in digital TV,
doesn't mean the whole grey market does.
Since she bought her box, many of her friends have gone out and bought one
too.
They are cheap (she paid £39) and easy to use (if my mom can use it, they
must be easy)
Stop judging everyone by your own standards
Loz |
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Buno
Guest
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| Posted:
Tue Aug 30, 2005 4:43 am Post subject:
Re: AD: Dreambox, Season/Logger, Funcard, microchips, progra |
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| Nick Burns could not be reached for comment. |
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cikrum
Guest
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| Posted:
Mon Sep 05, 2005 9:11 pm Post subject:
Re: HOw do i transfer recorded things from my bell pvr to co |
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| thank you i will try that |
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Not Read
Guest
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| Posted:
Thu Oct 27, 2005 10:30 pm Post subject:
Re: a simple request... an OTA HD PVR |
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On Sat, 22 Oct 2005 19:19:42 -0500, mango masher <mangomasher@puny.net> wrote:
| Quote: | All I want for Xmas is a HD PVR that can record one hd channel while I
watch another. One that would pull the tv guide ratings from the PBS
channel or whatever. One that would be free of charges to use, since I
just want to record ota. One that would be easy to use, like tivo.
I have the moxi by charter, but my stupid cable provider does not get
all ota hd channels., notably ABC in St louis.
I have hear of the sony hd dvr but you can't watch one channel while
recording another...(how dumb is that?, vcr's have done that for years).
I guess it would need two OTA HD tuners to accomplish that. a 250 gig
hd would be nice.
PC/Internet networkable would be a big plus.
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Set up a Windows Media Center Box with 2 ATSC tuners.
--nutz |
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Not Read
Guest
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| Posted:
Mon Oct 31, 2005 1:42 am Post subject:
Re: does anyone have a rock solid media center HDTV recordin |
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2 dvico fusion 5 lite tuners, nvidia 6600 pci-e board, intel d925x series MB.
Very solid. You will have to have an analog tuner, just to setup the atsc
tuners. (I turn all the analog channels off after setup) I use the wintv
pvr-2 usb model, so I can disconnect it after setup.
--nutz
On Sat, 29 Oct 2005 13:07:38 -0500, mango masher <mangomasher@puny.net> wrote:
| Quote: | Continuing in my frustration to record all the dang local HD channels,
which my charter cable MOXI unit does not have (notably ABC as it is a
sinclair affiliate). Not to mention the silly way moxi goes about its
menu processes to record a show. (I've given up trying to record JUST
one NEW episode of the Daily Show on Comedy central, as MOXI records
each and everyone of them every day, (about 5 episodes here in the
midwes on a daily basis)
Does anyone have a rock solid pc running media center with two HD tuners?
I have search for some hd turner cards, but I want to hear from some
people actually using them.
As always,
thanks.
Mango |
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Anonymous
Guest
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| Posted:
Sun Nov 13, 2005 3:59 am Post subject:
Re: www.dvd100.net Sin Canon ** cds y dvds Verbatim Traxdata |
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Trial
<maria@otonksrd.edu> wrote in message
news:Su8df.24152$yg1.10300@twister.auna.com...
| Quote: |
---
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AZ
Guest
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| Posted:
Sun Nov 13, 2005 4:01 am Post subject:
Re: www.dvd100.net Sin Canon ** cds y dvds Verbatim Traxdata |
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Trial
"Anonymous" <anonymous@verizon.net> wrote in message
news:sBtdf.707$9T4.642@trnddc04...
| Quote: | Trial
maria@otonksrd.edu> wrote in message
news:Su8df.24152$yg1.10300@twister.auna.com...
---
Sen hogekasi refopabe tixa tamamesil nigaf licekaparer medekodoxer lot
bifi semosonal seled gi .
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