DTV reception is much more difficult than analog

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Blue Cat wrote:

>
> I bought a Samsung SIR-T451 ATSC set top box last October, and, for the most
> part, I get excellent results on most of the local channels. However, with
> some channels I have problems with Multipath, which causes dropouts. Because
> of this I can't sell the idea of digital TV to my wife. The minute she fails
> to receive her favorite program, she will tell me that the system is no
> good. It is a shame that "5th generation chips", "Casper chips", or any new
> technology may not show up in future set top boxes.
>
>
We dropped cable because of reception problems that they couldn't or
wouldn't address. Went to Dish and my wife could not stand the lost
reception during rainstorms. Next was RCN microwave which is the worst
of them all since it cuts out because of wind or rain.

OTA analog is not to bad, digital got killed when I first set it up
because the only place we could receive it was in our back bedroom with
a directional antenna (though the entire apartment has a full view of
the Empire State Building about two miles away) and when I got my wife
to come see my setup and what HD looked like the reception dropped out
as we entered the room. She who wanted to cancel dish because of rain
fade that happened a couple times a month obviously did not want
something that didn't work if someone moved.

5th gen LG prototype solved that at least as long as the person was
behind the antenna and not in front of it. With COFDM I could walk all
over the apartment with a receiver and a piece of coax with my finger
touching it with perfect reception. My wife suggested that we get that.

I contend that COFDM modulation would cancel the wife factor completely,
no rooftop antenna needed in most cases especially as SFNs are built out
and not ugly indoor antennas either.

Bob Miller

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

Blue Cat wrote:

>
> I bought a Samsung SIR-T451 ATSC set top box last October, and, for the most part, I get excellent results on most of the local channels. However, with
> some channels I have problems with Multipath, which causes dropouts. Because of this I can't sell the idea of digital TV to my wife. The minute she fails
> to receive her favorite program, she will tell me that the system is no good. It is a shame that "5th generation chips", "Casper chips", or any new
> technology may not show up in future set top boxes.
>
>
It is not a "shame" that 5th gen technology will not show up in STB's.
It is a political scandal. First we had lies about 8-VSB's receive
characteristics back in 1999. Then we had Congress and the FCC go along
with thoughs lies giving the benefit of the doubt to those who were
lieing and "staying the course" with an acknowledged poorly performing
8-VSB (MSTV report 2001) when they said that they would put all their
engergies to work fixing 8-VSB which was going to take six months.

It is a "shame" that our FCC and Congress are being led around with a
ring in their noses by 8-VSB special interest.

They knew then how to fix it at least to make it work minimally well in
multipath and they knew then that it would cost to much to be comparable
with COFDM receiver cost. They know how to fix it now to and it still
cost to much. They will not market an 8-VSB 5th gen receiver until the
cost come down. They can hide that cost in top of the line integrated
sets so that is where you will find 5th gen LG tech.

You will not find it in RCA $300 HDTV sets or STBs for awhile. I am
talking to six different companies who are or have looked at LG 5th gen
chips. All of these companies have the same problem, they see no market
for the receivers they could make with this technology in the US at the
price. What other market is there for 8-VSB? Korea for one. I think you
might see expensive 5th gen STBs in S. Korea first.

Bob Miller

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

>If you can read and navigate using cursor buttons on a remote, you can
>click through the easy-setup and tuning wizard on new tuners. Some
>external tuners also walk you through the Aspect Ratio settings by
>asking if you have a conventional or widescreen TV.

Aspect ratios are still an issue. My receiver (US Digital, aka the
"Walmart box") has a setting so it knows I've got a 4:3 monitor.
It also knows it has to downconvert to 480i with S/Video. Some day
I'll get a better (and 16:9) monitor.

There are 4 settings for aspect ratio on my tuner, and I constantly
have to dink with them: Auto, Zoom, Letterbox, and Full Screen.
I hate "Full Screen"; it makes things out of proportion and it looks
strange. For many shows in actual 720p, I want "Letterbox". For
others, probably SD material that's been converted, I want "Zoom",
or I get the effect of "triple letterboxing" - a double-wide stripe
at the top and bottom, and one on the side. "Auto" seems to give
me the same as "Letterbox" every time I can remember.

Oh, yes, if I change the channel, the aspect ratio goes back to
"Auto". Now, how do I program a DVR (here, one using the external
digital tuner rather than having an integrated one) to change
channels with an IR blaster and set the aspect ratio depending on
what program it's recording? (Actually, right now, I leave it set
MANUALLY to the channel and aspect ratio I want, as no DVR seems
to know how to control the box.)

Gordon L. Burditt

 

[Guest]

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Drewdawg (nope@not.here) wrote in alt.tv.tech.hdtv:
> Bob's chance is coming this summer when Crown Castle starts its "nationwide"
> DVB-H service offering mobile TV & Radio in the L-Band.
>
> Bob has been on about COFDM SFN for years now and it appears it's finally
> coming to America.
>
> As far as the proof being in the pudding it appears to be dinner time. 🙂
>
> And I predict it's Bob who will be eating it. ;-) lol

Actually, an SFN probably will work OK. But, it can only deliver the same
programming across the SFN, not thousands of different signals, and that's
what makes it unsuitable for OTA TV in the US.

--
Jeff Rife | "Ho! Ha, ha! Guard! Turn! Parry!
| Dodge! Spin! Ha! Thrust!"
|
| -- Daffy Duck, "Robin Hood Daffy"

 

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inkyblacks@yahoo.com (inkyblacks@yahoo.com) wrote in alt.tv.tech.hdtv:
> I am willing to concede that Bob is probably right that we made a
> mistake to pick 8-VSB over COFDM

See, here's one more reason for people to keep refuting Bob's lies.

What technical proof do you have that show that COFDM would cover the
required areas using the single transmitter ("big stick") model that
is required by the US? And, what power would be required on the
transmitters to do this? Please provide proof, not speculation.

--
Jeff Rife |
| http/www.nabs.net/Cartoons/Dilbert/InstallVirus.gif

 

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L David Matheny (ldmnews1@netassoc.net) wrote in alt.tv.tech.hdtv:
> "Mark Crispin" <MRC@CAC.Washington.EDU> wrote in message news😛ine.WNT.4.63.0503291040200.6060@Tomobiki-Cho.CAC.Washington.EDU...
> <snip>
> > 2) The rotor is not integrated with the tuner. I would kill
> > for a TV with integrated ATSC tuner and rotor control.
> >
> That would be OK, but slow and cumbersome. I would kill for
> an ATSC/NTSC tuner with a built-in antenna switcher to select
> each channel from one of three or four general-purpose inputs
> (ATSC and/or NTSC). I don't mind running separate coaxial
> feeds down from each outdoor antenna or preamp.

Most good ATSC STBs have two separate antenna inputs. The MyHD cards
even integrate them together in such a way that it does exactly what you
want: enter a channel number and it remembers which input should be used
to get that channel.

--
Jeff Rife | "This? This is ice. This is what happens to
| water when it gets too cold. This? This is
| Kent. This is what happens to people when
| they get too sexually frustrated."
| -- Chris Knight, "Real Genius"

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

Charles Tomaras (tomaras@tomaras.com) wrote in alt.tv.tech.hdtv:
> Well now in my market the ABC affiliate uses their -2 sub channel for a
> duplicate of -1 which I can't figure out why?

Without examining the transport stream, it's hard to tell.

Locally, the WB station had four subchannels for a while: 50-1, 50-2, 75-1,
and 75-2, but there was only one video stream and two audio streams. All
four sub-channels used the single video stream and the audio stream went
with the subchannel number, so they could provide alternate audio services
easily.

So, there is no telling what your ABC station is really doing for sure.

> The NBC affiliate has a
> weather channel on their -2 sub. Auto scan also picks up the NTSC versions
> of these stations as well. It's just really confusing for the average person
> to deal with all of this plus the aspect ratio issues. I don't have an
> answer save for...I have a hard time recommending it to someone who isn't
> pretty much up to date with their technology abilities.

Blaming the STB and ATSC for the brain dead behavior of some broadcasters
hardly seems fair.

--
Jeff Rife |
| http/www.nabs.net/Cartoons/FoxTrot/GutterBall.gif

 

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Blue Cat (bluecat22@go.com) wrote in alt.tv.tech.hdtv:
> > Are you certain that the problem is multipath? As in, have you had your
> > signal tested with a spectrum analyzer?
> >
> No, but I am not too far from their tramsmitters. The stations that I have
> problems with in digital, show up with ghosts in analog.

This tells you nothing unless their channel numbers are very close
together. Ghosting on a VHF-Low channel (2-6) doesn't mean that you
would have ghosting on a UHF channel (14-69) from the same transmitter
location.

For me, I have the ultimate proof that multipath isn't the problem people
think it is. My local WB transmits analog on channel 50 at 5000kW and
digital on channel 51 at 150kW from the same antenna. The analog broadcast
is a ghost-filled snowy mess, while digital is perfect.

--
Jeff Rife | "My God, what if the secret ingredient is people?"
| "No, there's already a soda like that: Soylent Cola."
| "Oh. How is it?"
| "It varies from person to person."
| -- Fry and Leela, "Futurama"

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

Jeff Rife wrote:
> Drewdawg (nope@not.here) wrote in alt.tv.tech.hdtv:
>> Bob's chance is coming this summer when Crown Castle starts its
>> "nationwide" DVB-H service offering mobile TV & Radio in the L-Band.
>>
>> Bob has been on about COFDM SFN for years now and it appears it's
>> finally coming to America.
>>
>> As far as the proof being in the pudding it appears to be dinner
>> time. 🙂
>>
>> And I predict it's Bob who will be eating it. ;-) lol
>
> Actually, an SFN probably will work OK. But, it can only deliver the
> same programming across the SFN, not thousands of different signals,
> and that's what makes it unsuitable for OTA TV in the US.

Agreed, but I'm thinking there will be areas of the US without SFN
reception. Crown Castle has a tall order to fill if they expect to offer
*everyone* this service. I'd like to see their "Coverage" map when it comes
out.

When it comes to the boonies (like Dover, DE), big sticks work! ;-)

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

Drewdawg (nope@not.here) wrote in alt.tv.tech.hdtv:
> Agreed, but I'm thinking there will be areas of the US without SFN
> reception. Crown Castle has a tall order to fill if they expect to offer
> *everyone* this service. I'd like to see their "Coverage" map when it comes
> out.

Oh, yeah, agreed. I'm sure it will look a *lot* like cell phone coverage
maps. The only advantage it will have over cell phone is that the number
of users shouldn't affect it, since it is transmit-only at the towers.

--
Jeff Rife |
| http/www.nabs.net/Cartoons/OverTheHedge/Macarena.gif

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

"Jeff Rife" <wevsr@nabs.net> wrote in message
news:MPG.1cb540eed6fd8074989c47@news.nabs.net...
> Charles Tomaras (tomaras@tomaras.com) wrote in alt.tv.tech.hdtv:
>> Well now in my market the ABC affiliate uses their -2 sub channel for a
>> duplicate of -1 which I can't figure out why?
>
> Without examining the transport stream, it's hard to tell.
>
> Locally, the WB station had four subchannels for a while: 50-1, 50-2,
> 75-1,
> and 75-2, but there was only one video stream and two audio streams. All
> four sub-channels used the single video stream and the audio stream went
> with the subchannel number, so they could provide alternate audio services
> easily.
>
> So, there is no telling what your ABC station is really doing for sure.
>
>> The NBC affiliate has a
>> weather channel on their -2 sub. Auto scan also picks up the NTSC
>> versions
>> of these stations as well. It's just really confusing for the average
>> person
>> to deal with all of this plus the aspect ratio issues. I don't have an
>> answer save for...I have a hard time recommending it to someone who isn't
>> pretty much up to date with their technology abilities.
>
> Blaming the STB and ATSC for the brain dead behavior of some broadcasters
> hardly seems fair.

No blame here..I'm just giving the realities of HDTV in Seattle. I can deal
with it and I'm very pleased with my setup. I cannot however recommend it to
techologically average friends because I don't want to be thier tech support
person.

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

Yesterday I tried one more position for my indoor antenna and found
that by raising it by just one more foot, I was for the first time able
to get all local digital channels in the middle of the day without
moving the position of the antenna. Who could imagine that one lousy
foot would make such a big difference! So it has taken me 10 months to
find the sweet spot in my apartment for my antenna, and I have to use a
specific indoor antenna (Silver Sensor) with an antenna amp (Zenith
indoor amp) to get the system to work.

How are old ladies going to deal with over-the-air digital TV? The
other thing I don't like is the labeling of channels like 9.1 and 9.2.
This scheme is too complex for most people. Unless you are technically
inclined and have patience, or are lucky enough to be able to have a
good outdoor antenna, I think OTA digital is too much work and
complexity for the elderly and for women.

Better receiver chips would help.

IB

 

[None]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

Mark Crispin <mrc@CAC.Washington.EDU> wrote:

<snip>
>I don't have much of a problem with the tuners. They output 1080i
>so the TV's aspect ratio is locked. The tuners also lock their
>aspect ratio on HD or widescreen SD programming.


AR is not locked on *all* TVs and STBs.
It depends on the brand/model of equipment.

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

On Thu, 31 Mar 2005, inkyblacks@yahoo.com wrote:
> How are old ladies going to deal with over-the-air digital TV?

The same way they dealt with over-the-air analog TV. Either they have a
professional set up the antenna, they "assume FOX viewing positions", or
they decide for simplicity and go with cable or satellite.

-- Mark --

http/staff.washington.edu/mrc
Science does not emerge from voting, party politics, or public debate.
Si vis pacem, para bellum.

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

Jeff Rife wrote:
> Drewdawg (nope@not.here) wrote in alt.tv.tech.hdtv:
>
>>Agreed, but I'm thinking there will be areas of the US without SFN
>>reception. Crown Castle has a tall order to fill if they expect to offer
>>*everyone* this service. I'd like to see their "Coverage" map when it comes
>>out.
>
>
> Oh, yeah, agreed. I'm sure it will look a *lot* like cell phone coverage
> maps. The only advantage it will have over cell phone is that the number
> of users shouldn't affect it, since it is transmit-only at the towers.
>
Today's pocket cell phones are in the 100 milliwatt area. One milliwatt
is one-thousandth of a watt. So cell phones operate at 1/10th of a Watt.

This determines the size of the cell they can operate in. The cell
towers themselves operate at around 10 Watts.

I don't know what the limit is for Crown Castle whose spectrum is in the
1.5 GHz area but Qualcomm in the 700 MHz spectrum they will use is
limited to 50,000 Watts. The Qualcomm power level is therefore as much
as 500,000 times greater than a cell towers power level.

I believe that would suggest a slightly bigger coverage map per transmit
site and over all better coverage.

For example at 1000 Watts of ERP we were able to receive mobile with
COFDM at 20 miles. With only 1/10th of a watt of power a cell phone must
have a cell tower within a mile or so. Makes for radically different
coverage maps. The Crown Castle and Qualcomm networks target cell phone
users so initially they will have similar coverage maps but far fewer
cells. However when they are fully deployed they will cover virtually
the entire country. Your cell phone will receive DTV in a far greater
coverage area than you can make a call in.

Bob Miller

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

inkyblacks@yahoo.com (inkyblacks@yahoo.com) wrote in alt.tv.tech.hdtv:
> How are old ladies going to deal with over-the-air digital TV?

Easily, *if* they are dealing with OTA analog TV right now.

Many people are re-discovering the lost art of OTA TV reception because
digital TV has features that make it worthwhile to try. People that
don't care about those features today and who don't use OTA for their
local analog stations will keep doing what they have been doing: get the
digital locals from their cable or satellite provider.

--
Jeff Rife | Coach: What's the story, Norm?
|
| Norm: Thirsty guy walks into a bar. You
| finish it.

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

Alan,

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. In the apartment where it was
tested, they picked up stations that they could not pick up before and
picked up all signals detected with a scope. There may be situations
where even the best receiver will not help, but certainly if reports
from Bob Miller and Sinclair are true about the LG design, it is a big
boost to indoor reception in America.

IB

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

<inkyblacks@yahoo.com> wrote in message
news:1112295350.890069.113640@l41g2000cwc.googlegroups.com...
> Yesterday I tried one more position for my indoor antenna and found
> that by raising it by just one more foot, I was for the first time able
> to get all local digital channels in the middle of the day without
> moving the position of the antenna. Who could imagine that one lousy
> foot would make such a big difference!

Makes perfect sense... you have to remember how short UHF waves are...
namely between 1-2 feet long.

so moving your antenna 1 foot was enough to completely change the Rayleigh
multipath interference pattern and take you from a null to peak

the fact that UHF signals are the same size as human sized stuff accentuates
the multipath effects... this is a particular issue for RFID where gain
margins are ridiculously low and multipath is killer.

 

[Guest]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

Bob,

Nice pictures Bob!

Alan,

You need to call your mother and ask her to give you a lesson in
manners.

IB

 

[Alan]

Archived from groups: alt.tv.tech.hdtv,alt.video.digital-tv (More info?)

In article <1112295350.890069.113640@l41g2000cwc.googlegroups.com> "inkyblacks@yahoo.com" <inkyblacks@yahoo.com> writes:
>Yesterday I tried one more position for my indoor antenna and found
>that by raising it by just one more foot, I was for the first time able
>to get all local digital channels in the middle of the day without
>moving the position of the antenna. Who could imagine that one lousy
>foot would make such a big difference!

Anyone who has ever looked at the issues of indoor TV antennas.


> So it has taken me 10 months to
>find the sweet spot in my apartment for my antenna, and I have to use a
>specific indoor antenna (Silver Sensor) with an antenna amp (Zenith
>indoor amp) to get the system to work.

Or, an outdoor antenna. As many of us have explained, there are reflections
of the signals indoors, blockages by metal in the walls, diffraction around the
edges (such as through windows).

There will be dead spots.

The dead spots will vary as people move around in the room


>How are old ladies going to deal with over-the-air digital TV?

By putting the antenna outside, where it belongs.

> The
>other thing I don't like is the labeling of channels like 9.1 and 9.2.
>This scheme is too complex for most people. Unless you are technically
>inclined and have patience, or are lucky enough to be able to have a
>good outdoor antenna, I think OTA digital is too much work and
>complexity for the elderly and for women.

Oh, you think the elderly and women are incapable? What a snot you
are!


>Better receiver chips would help.

No, they wouldn't. If the signal is not present in a spot, it does't
matter what receiver you use.


Alan