Re: Washington Post Knocks Digital Reception

G-squared wrote:
On May 23, 4:45 am, robmx <ro...@xxxxxxxxxxxxx> wrote:
Tantalust wrote:
"robmx" <ro...@xxxxxxxxxxxxx> wrote in message
news:T_2dnR5LfKj8KKnVnZ2dnUVZ_h3inZ2d@xxxxxxxxxxxxxxxx
phil-news-nos...@xxxxxxxx wrote:
On Wed, 21 May 2008 07:48:25 -0400 Tantalust <Tantal...@xxxxxxxxxxxx>
wrote:
| <phil-news-nos...@xxxxxxxx> wrote in message |
news:g0vgc001oi7@xxxxxxxxxxxxxxxxxxxx
|> On Tue, 20 May 2008 15:56:00 GMT Joe Moore <mun...@xxxxxxxxxxxxxxx>
wrote:
|>
|> | |>
http://www.washingtonpost.com/wp-dyn/content/article/2008/05/19/AR200...
|> |
|> | From the article:
|> | "Airplane traffic used to cause seconds-long bouts of fuzziness in
the
|> | analog picture. But digital signals are more sensitive to
disruption,
|> | so the sound mutes and the screen freezes, sometimes dissolving into
a
|> | cascade of pixels."
|>
|> Then what we need to do is find out who advertised that digital
reception |> would
|> be fine for everyone with rabbit ears. Oh wait, that was the
government.
| | Exactly when, or where, or how did the government advertise that?
Implied in their digital TV promotions.
Also the Government in the form of various Congressional persons and many
of the highest officials of the FCC saw this video and most agreed that it
represented a FAR BETTER modulation.
We were receiving from a 100 Watt transmitter at 1 Kw ERP. Compare to
typical DTV broadcast levels of up to 1000 Kws in the US.
And we were using single whip and dual whip $2 to $10 OMNI antennas in the
WORST RF environment in the world, New York City, while driving which
represents the WORST multi-path environment in the world.
When you are driving everything becomes a source of multi-path. The main
signal become just another multi-path signal.
We could have this modulation or its far superior successor, DVB-T2, in
the US instead of the garbage modulation 8-VSB.
www.viacel.com/bob.wmv
Bob Miller
Everyone should see this clown's video and hear how he admits to impulse
noise interference when the reception freezes.
Ohhh, quick bob, turn the camera away. . . . .ooops.
Not impulse noise, loss of signal. DO watch the video. This is mobile in
the worst RF environment in the world using 100 Watt transmitter at 400 ft.

Compare to 1600 ft and 1000 times the power used by 8-VSB in the same
place that has major problems being received in a fixed location with a
directional antenna.

Also this is from one transmitter. If you were to deploy a mobile
service in New York City you would build an SFN of small transmitters as
Qualcomm has done and Dish and AT&T may do.

You don't have to watch my video anymore. Mobile is a reality in NYC
today with Qualcomm and will be soon by ALL broadcasters using a KLUDGE
of 8-VSB.

As predicted the US will have the worst of all worlds as pertains to the
OTA spectrum saddled with 8-VSB. We will have mobile DTV that will kill
HDTV OTA while using the spectrum extremely inefficiently. We could have
had HDTV OTA that was receivable mobile that wasted NO spectrum for
mobile. Now a part of the spectrum will be segmented off to be used by
one of the KLUDGE fixes to 8-VSB, A-VSB or MPG or whatever they come up
with next.

The worst possible outcome. And in the meantime, over the last nine
years, 8-VSB has impeded the adoption of OTA DTV. Very few people even
know of OTA DTV.

Bob Miller

Well that's just a stupid test. 400kW less than 1/2 mile? What did
COFDM do in that case - or did you even try it? You're overloading the
bejeesus out of the front end.

I have no idea of what you are talking about. We were testing on high UHF channels that need a lot more power than lower UHF or VHF. We had an ERP of 1000 Watts from a 100 Watt transmitter located at 400 ft. of altitude on channels 54 and 59. In the same Manhattan 8-VSB channels were and are not receivable while broadcasting from 1600 ft. and 300 kW, 500 kW etc. with clear line of sight of the transmitters.

I could defeat a 5th generation LG receiver with a directional antenna that was facing the Empire State Building and only 1.5 miles away by just standing off to the side in one particular location or walking in front of the antenna. And I was ecstatic over that 8-VSB receiver.

At the same time I could take a COFDM based receiver and drive with it around the base of the Empire State Building with perfect reception in the clutter of traffic and building while mobile. The COFDM transmission was from the same location that I could easily defeat 8-VSB or 1.5 miles from the Empire State Building.

That is I could easily defeat 8-VSB 1.5 miles with clear line of sight and a directional antenna from the Empire State building in a fixed location 400 ft up on the AT&T building. Broadcasting from that same location with COFDM I could easily receive the COFDM broadcast using and omni antenna mobile and nothing I did could defeat the signal.

And I had the LG engineers who designed the 5th generation receivers standing right there watching. They admitted to me that 8-VSB would never be anywhere near as good as DVB-T COFDM.

Bob Miller
.

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