ATSC hand held TV

[wb4jfi at knology.net]

Or was it Ibiquity??
Terry, WB4JFI



-----Original Message----- 
From: wb4jfi at knology.net
Sent: Monday, April 28, 2014 9:57 PM
To: Chip Fetrow ; tacos at amrad.org
Subject: Re: ATSC hand held TV

Sorry Chip, but the COFDM/ATSC decision was not as black-and-white as you
make it out to be (implied TV joke).  Hindsight and forgetting a lot of
timing issues can make any decision look bad.  While I attended very few
(maybe one or two) ATSC meetings, I was involved at the time with MSTV (who
had some of those ATSC members) and the NAB, and was very involved in making
the DTV decisions for over 20 Gannett stations around the country.  From
W*USA in DC to WLBZ in Bangor, Maine.  It was a LOT more complicated than
your simplistic paragraph can describe.

The first issue was timing.  The decision had been made to support the Grand
Alliance before terrestrial COFDM became viable in the US.  Remember, most
of the places that had the option for COFDM for terrestrial had 8MHz TV
channels, not 6MHz, like the U.S.  That extra 2MHz made a huge difference at
the time.  Satellite TV of the time used even wider RF channels, even with
half-transponder usage.  If I remember correctly, at the time, true HDTV
(1080i) was difficult to put inside the COFDM stream at 6MHz.  Certainly,
most other uses of COFDM AT THE TIME THE DECISION WAS MADE were NOT
transmitting HDTV, but were only supporting SD material.  The COFDM
proponents seemed to favor multiple, SD channels instead of High-Def.

There was only one (non-US) company that provided COFDM
encoders/transmitters at that time, and it was at least partially owned by
the Sinclair Broadcast Group.  Sinclair stood to earn a LOT of royalties in
licensing if COFDM was chosen.  THAT's the reason THEY pushed COFDM.
Regardless, there were several COFDM/ATCS shoot-outs done around the
country.  Yes, COFDM could be received better by MOBILE receivers, but HD
QUALITY TO EVERYONE'S HOMES would have been sacrificed - at least "until
technology caught up with the market".  Whenever that would happen.....

COFDM also requires even more headroom in peek-to-average-power at the
transmitter (versus ATSC, which has a higher headroom requirement than
NTSC), I think it was quoted as an ADDITIONAL 5-6dB over ATSC.  At time of
the decision, few broadcasters could afford tube UHF transmitters at that
power level.  A one MegaWatt ATSC transmission facility became 4 MegaWatts
of COFDM for the same coverage!!  On UHF, Unheard of!

Remember also, the FCC was pressuring TV broadcasters to move forward with
the DTV transition, because they wanted (needed) the extra spectrum back to
auction off.  There was a lot of pressure from both the FCC and Congress to
move forward, and going back to the drawing board with COFDM would have been
frankly impossible timewise, and a politically suicidal decision.

Even the Consumer Electronics Assoc (CES) was applying heavy pressure.  They
wanted it done, done once, done right.  And BTW, right away.  There was
money to make in new TV sets.  They out and out said they would NOT do both
ATSC and COFDM, and at the time, ATSC was the only working game in town.

IDIOTS?  I think not.

Regarding high-VHF versus UHF:
We had to make decisions for 23(?) full-power Gannett TV stations as to what
channels we would end up on at the end of the transition.  We had the whole
gambit, low-VHF, high-VHF, UHF, for both NTSC and DTV transmitters.  We had
a LOT of decision points at each market.  Your comment regarding channels 7
& 9 coverage are based on outside antennas, and only in certain areas.
Remember that channels 7 & 9 made their decisions separately, as 9 is owned
by Gannett, while 7 was owned by Albritton.  Both stations SHARE the same
antenna, whether the high-VHF or the UHF panels.  In fact, most high-VHF
analog stations around the country chose to go back to their high-VHF
channel at the end of the transition.  There have been some coverage issues
with that decision, but usually it's at the fringe of the coverage area, and
sometimes related to out-of-market interference from close-by co-channels.

One of the factors in going back to high-VHF channels was the OVERALL better
RF coverage per-Watt of VHF versus UHF.  UHF also had more problems with
strong signal level but poor reception due to bad reflections.  When Gannett
was in Rosslyn, we could literally SEE the towers in upper-Northwest, but
had a devil of a time decoding DTV signals.  You could look at a spectrum
analyzer and SEE the reflections taking out large sections of a station's
signal.  Yes, COFDM may have helped with that, but maybe not.  And that
decision was long in the past.

Another comment is that most people pick up their TV signals via cable or
satellite these days, at least for their primary TV broadcast signals.
Plus, VHF antennas have ALWAYS been available, and the typical consumer has
always had more trouble with picking up over-the-air UHF stations than VHF.

As mentioned above, the cost of purchasing and then maintaining a
solid-state high-VHF transmitter is a small fraction of that of a tube-based
UHF DTV transmitter.  The monthly electric bills alone are an order of
magnitude or more different.  Then, there are the replacement tubes cost and
other high-voltage problems, the nasty issue of tube coolant (glycol/water
mix) which is environmentally bad, and a whole host of other problems.  The
cost of personnel is higher as well, a UHF tube DTV transmitter requires
more, specialized, baby-sitting than a solid-state VHF DTV transmitter.
Keep in mind, you will need at least two, and usually three tube cabinets in
a UHF DTV transmitter.  Plus, you may need more for redundancy.

W*USA had two old Harris VHF tube transmitters for their analog plant, while
WJLA has a new Harris Platinum solid state analog transmitter.  So, as far
as capital expenditures go, it would actually been cheaper for W*USA to stay
on the UHF channel, except for the above points.  In the end, it was cheaper
and more effective to buy a new DTV VHF transmitter and go back to RF
channel 9, than to keep running their UHF tube DTV transmitter.  It would
also provide better overall coverage.  Many (most) other analog high-VHF
stations around the country made a similar decision.

We had a station in Cleveland whose analog was on channel 3 (WKYC).  They
ended up on a UHF channel I think.  We had a station in Greensboro, NC, that
was an analog 2, and DTV channel was 51(?), the highest TV broadcast channel
left.  I believe they stayed on the UHF channel.  Then, there were stations
in Portland and Bangor that were 6 and 2, respectively.  I think they both
ended up staying on their low-VHF channels.  Final channel decisions were
often very complicated.

The biggest problem with low-VHF channels was interference from many, many
sources.  Both fellow broadcasters (especially when the "skip" is in), to
garage door openers to diathermy(sp) machines, welders, etc.  Small market
stations might end up going out of business if they have to pay the electric
and maintenance bills for a three-cabinet UHF DTV transmitter.  A top market
station should be able to afford the operating costs of a full-power UHF DTV
transmitter, but if the cable/satellite penetration in the market is high
enough, they STILL might not want to pay the huge operating bills.

Every station and every market is different.  The decisions had to be
weighed, based on each station's points.  I can't tell you how much of my
time over more than eleven years was spent on the DTV transition.

In conclusion, I was NOT one of the "IDIOTS" that you mentioned, but I DID
live through almost all of the DTV transition, and know many of those
"IDIOTS". Not to sound crass, but they were/are a LOT smarter than you or I
could hope to be.  They knew and understood many of the technical,
financial, and political decision points that you glossed over.  There is a
lot in this world that I will never understand, but I WAS THERE during much
of the DTV process.

Hey, how's that RADIO digital transition coming???  Anyone selling those
great digital radios for your car anymore????  (Yes, I came to Gannett while
we still owned a significant part of the technology behind "Ubiquity",  I
met some of the SRI and other folks involved in that, so I personally like
COFDM).  How soon are the power-wasting ANALOG radio transmitters going to
be shut down?  IBOC anyone?

In summary to my conclusion, your "IDIOTS" comment is simplistic, misguided,
and completely misplaced.  And who is Frank?
Sorry.
Terry, WB4JFI


-----Original Message----- 
From: Chip Fetrow
Sent: Monday, April 28, 2014 12:54 AM
To: tacos at amrad.org
Subject: Re: ATSC hand held TV

Item 1, though it wasn’t your item 1, 8VSB does not deal with a mobile
receiver well at all.  Right now, some broadcasters are looking at ways to
give up picture quality or additional video feeds to try to make mobile
reception better, with only a little success.  COFDM would have been a much
better idea, but he Grand Alliance didn’t think mobile reception was a big
deal.  Apparently they didn’t bother to speak with the installers of mobile
video systems that used NTSC and satellite TV.  Frankly, let me write —
IDIOTS!

Interestingly, 8VSP does play well with other things in the 6 MHz channel.
WPVI, Channel 6, and Channel 6 RF, in Phili did a hot cut to Channel 6, and
is still there today.  They ran an FM transmitter at 88.75 MHz, or there
abouts, after the cut.  They had encouraged people to listen to them on 88.7
MHz in their cars.  Close enough to 88.75 back in the days of NTSC.  Hell, I
used to listen to them, and also Channel 6 out of Richmond, VA while on the
road.  There were some inquiries to and from the FCC about the legality, and
the FCC basically said, “Um, we don’t know, but it doesn’t seem like a good
idea to us.”  I am sure that was some low level lackey, but they shut it
down.

However, there a all kinds of applications for LPTVs on Channel 6 all over
the country.  In the industry, they are called Frankinn FMs.  I don’t recall
the exact date but those low power TVs and translators are going to be
forced to go to ATSC so it won’t last forever.

OK, #1, mobile sucks.

#2, the current chip sets for ATSC are very much power hogs.  I also have a
Auvio potable.  It works GREAT, when you can see the transmit antennas, like
outside Hara, but I get nothing in Sterling.

#3, though you didn’t ask.  WUSA hot cut back to Channel 9, and WJLA hot cut
back to Channel 7.  Neither have worked well.  In DC you must have a
VHF-highband antenna in addition to UHF.

Of course CBS stayed on 2 in Chicago.  Just guess how well that is going!!!
Noise at Lowband just rips 8VSB a new….  Highband too, but to a lesser
extent.

I could go on a rant, but I won’t.

—chip

On Apr 27, 2014, at 1:00 PM, tacos-request at amrad.org wrote:

> Message: 2
> Date: Sat, 26 Apr 2014 15:49:20 -0400
> From: Richard O'Neill <richardoneill at earthlink.net>
> To: tacos at amrad.org
> Subject: Re: ATSC hand held TV
>
>  Alex, I have some experience using a little 3.5" Auvio battery
> operated digital TV, mostly sitting (not driving) in my car and while
> camping. Using the built-in antenna I don't receive much in the Waldorf,
> Maryland area either. The tiny whip antenna isn't very good at capturing
> low power digital transmissions unless very close to the station's
> antenna. Fortunately my TV has antenna, earphone and external power
> jacks. When connected to an old RCA 'flying saucer' amplified antennas I
> currently receive more than 40 channels from DC, Va and Baltimore area
> broadcasts.
>
>  I've also had very good reception when connected to an indoor VHF-UHF
> amplified antenna while in my camper van, stopped for the night near
> large cities such as Indy and St. Louis. One of the biggest drawbacks to
> these little sets is their hefty power consumption. My Auvio TV runs on
> AA cells but I power it from a 6V, 7AR gel cell. It eats AA cells much
> too fast. The antenna amp is powered from the car's 12 cigarette lighter
> socket while the antenna sits on the van's dash or roof. I haven't tried
> reception while moving but past experiments with analog TV suggest
> reception would most likely be poor to unwatchable.
>
> Richard
>
>
> On 4/26/2014 2:44 PM, Alex Fraser wrote:
>> I bought a used Digital Prism atsc-300 today.  It works, but I can't
>> pick up many channels in Woodbridge.  This little box only has a small
>> telescoping whip on it.  I'll play around clipping on external
>> antennas, but I think it will come to opening it up and soldering on a
>> jack of some sort.  How does digital TV handle motion, like driving?

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