Wind freezing/interrupting Digital TV Signal

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tonybackache
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Wind freezing/interrupting Digital TV Signal

Post by tonybackache » Wed Apr 16, 2008 5:00 pm

Trees & wind combination is wrecking my DTV viewing.
What can I do to improve Digital TV Signal. Without strong winds rabbitt ears pull in a great signal. At night DTV signal from 60-70 mile away is great!
Station is less than 10 miles away there is some tall trees in my yard & across the street. If I have to go above trees could be expensive! Analog signal isn't a problem on the same rabbitt ears.
There is some DTV antennas on E-Bay but I have no idea what to purchase?
http://cgi.ebay.com/HDTV-REMOTE-CONTROL ... dZViewItem
I like the built in rotor feature that requires no extra cables.
I would like to mount in attic if possible. My house has tall vertical open space.

Would a DTV amplifier help?

Bigglez
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Re: Wind freezing/interrupting Digital TV Signal

Post by Bigglez » Wed Apr 16, 2008 6:09 pm

Greetings Tony,
tonybackache wrote: Trees & wind combination is wrecking my DTV viewing. What can I do to improve Digital TV Signal.
A better antenna is your only option. If you are using a set top
antenna today, any outdoor antenna would be an improvement,
even if you are unable to clear the obstructing trees. An antenna
tuned for that particular station, and pointed accurately will
always beat a set top antenna.

Most likely the DTV signal is at lower power than the previous
analog NTSC signal.

If the station installed a new transmitter they may have gone
for lower power, and may plan to repurpose the old analog
transmitter in the future. The old transmitter would not operate
for DTV without modification. The DTV signal is approximately
four times weaker (-6dB) due to the different modulation
scheme used for digital transmission. In fact, the transmitter
and your receiver operate exactly the same as before except
the "intelligence" is a digital code stream instead of an analog
power level.
tonybackache wrote:Would a DTV amplifier help?
Probably not. An amplifier would also increase the noise
along with the signal, and may contribute it's own noise.

I'd contact the CE (Chief Engineer) at the station(s) with
lowered DTV performance and ask what they plan to do.
If my guess is right they may have the option to step
up the DTV power when the analog transmitter is shut down.

Let us know what you are told.

Comments Welcome!

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Janitor Tzap
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Post by Janitor Tzap » Thu Apr 17, 2008 10:30 am

tonybackache,

I live some 50+ miles from the DTV transmitters.
{My Antenna is a Omni Directional Powered Antenna.}
I see the same problem of weak signals.
{On Screen Signal meter showing less than 30%.}
Thus, the picture breaks up, and drops out intermittently.
This happens the most when a storm comes through.
The problem of signal strength may change after the February 19th 2009 dead line.

But I agree with Bigglez.
An outside antenna will help.

Your TV or Converter Box may have the "SmartAntenna" jack.
Here is an Antenna that plugs into it.
Sylvania No#DTA5000, Cost ranges $80 -$100.
Here's a review of the Antenna.
http://www.epinions.com/Sylvania_Dx_Ant ... y_~reviews

I checked out this Antenna for myself.
But found that it was no better than my current Antenna. :???:


Signed: Janitor Tzap

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Bob Scott
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Post by Bob Scott » Thu Apr 17, 2008 10:41 am

Janitor Tzap wrote:I live some 50+ miles from the DTV transmitters.
{My Antenna is a Omni Directional Powered Antenna.}
I see the same problem of weak signals.
An outside antenna will help.
What frequencies do DTV transmitters use? VHF? UHF too? It's good to know this if you are shopping for antennas.

Bob

Bigglez
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Post by Bigglez » Thu Apr 17, 2008 11:06 am

Greetings Bob,
Bob Scott wrote:What frequencies do DTV transmitters use? VHF? UHF too? It's good to know this if you are shopping for antennas.
FCC wrote:Question: What are the channel assignments for digital television?

Answer: Under the FCC spectrum plan, we have provided most existing broadcasters with access to a 6 MHz channel for digital broadcasting within a core digital TV spectrum, i.e., TV channels 2 to 51. Because of the limited availability of spectrum and the need to accommodate all existing facilities with minimal interference among stations, however, during the transition some broadcasters would be provided DTV channels outside of this core spectrum (channels 52 to 69). These broadcasters would have to move their DTV operations to a channel in the core spectrum when one became available. Broadcasters whose existing NTSC channels were in the core spectrum could move their DTV operations to their NTSC channel at some time in the future. Broadcasters whose DTV transition channel and existing NTSC channel were both outside of the core area could obtain a new DTV channel when channels in the core spectrum are recovered.
After the transition period (2006), the VHF channels (2-13) will remain available for DTV and the analog TV service will end on all channels.
Quoted from here.(last reviewed/updated 2/27/08 ).
I think it's done on a case by case basis, so contacting the
station's CE is the only sure answer.

Comments Welcome!

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haklesup
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Post by haklesup » Thu Apr 17, 2008 12:13 pm

For the most part, DTV use frequencies that are compatible with traditional VHF antennas.

I am using an Aerial antenna that is probably 20 years old (came with the house) and pointed in for all I know is a random direction (rusty rotor) and I get good reception on all the stations I should be getting for my area. I have not compared this reception to a set top antenna. I did need to replace the original 300 ohm cable with RG-6 coax for compatibility though, this required putting a matching transformer on the antenna, no big deal except for climbing the roof and standing on my toes at the peak while looking straight up with my arms over my head (a good trigger for fear of heights)

I checked for a friend a while back and these antennas are not very expensive but installation is a pain. Attic location should be Okay.

An antenna amplifier is not necessary unless you are splitting the signal to more than 2 TV sets. I always recommend an amplified splitter for more than 2 loads particularly with cable. If you use one anyway, it shouldn't hurt.

tonybackache
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Received Answer From Local TV Station Chief Engineer

Post by tonybackache » Thu Apr 17, 2008 3:08 pm

Your problem is not likely to be a signal strength issue as much as it is a signal quality one. Indoor rabbit ears are highly susceptible to picking up reflected signals and other signal variations which easily “confuseâ€

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haklesup
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Post by haklesup » Thu Apr 17, 2008 3:35 pm

Each cable outlet is a dedicated run but looks as if TVs 1 & 2 will need another coax line dropped to each set from outside antenna ;(
I don't get that comment, Are you running a seperate coax from each TV all the way back to a central antenna with the splitter located close to or on the antenna. I would just run one coax to a convenient location and use an amplified splitter to go to each of your 3 (is it) sets from there. Splitting a signal in two then doing it again and again down stream (daisy chain style) is not recommended but commonly practiced.

"Optimized for HDTV" means the rabbit ears have no UHF antenna like analog ones did. "Best within 20 miles" doesn't sound very impressive, but okay if you live in a metropolitan suburb.

Multipath can be a problem but generally is much less so than with an analog signal. A good ATSC tuner will lock onto only one data stream. This only works with a stationary antenna. I read somewhere that multipath reception is difficult to correct for with a moving antenna thus making mobile HDTV reception unlikely. So what, analog TVs never made it in cars either. Full HDTV is overkill for a cell phone screen. It may be that the old analog frequencies in part offer a solution to mobile DTV in the form of another broadcast standard.

tonybackache
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Coax runs

Post by tonybackache » Thu Apr 17, 2008 4:05 pm

My TVs 1 & 2 use present coax drop for Satellite reception.

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Janitor Tzap
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Post by Janitor Tzap » Sat Apr 19, 2008 11:35 am

This is the Antenna setup I currently have......
Image

I've connected the Converter Tuner Box between the Diplexer Antenna Out,
and the DSS Reciever Antenna Input.
Thus, I can still use the VCR for Playback or Recording.
The only problem is I can't have the Coverter Box,
and the Satellite Reciever both on at the same time.
Also this One Converter Box I have: RCA DTA800B.
It doesn't not let analog signals pass though it when it is turned off.


Signed:Janitor Tzap

tonybackache
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Converter box blocks out analog signal

Post by tonybackache » Mon Apr 21, 2008 6:44 am

I also have the RCA DTA 800B converter box. Frustrating it won't let analog signal to pass through when it is in off position.

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philba
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Post by philba » Thu Apr 24, 2008 8:43 am

Here's a new york times article on the digital TV switchover problem. worth a read. note - hit the "skip ad" button on the upper right to avoid an incredibly stupid ad.
http://www.nytimes.com/2008/04/24/techn ... atD5F51eLQ

Bigglez
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Post by Bigglez » Thu Apr 24, 2008 9:42 am

Greetings Phil,
philba wrote:Here's a new york times article on the digital TV switchover problem. worth a read. note - hit the "skip ad" button on the upper right to avoid an incredibly stupid ad.
Good article, but it didn't indicate that DTV transmitters
may increase power once the analog channels and
analog transmitters are turned off.

Also, it's a bit misleading to say: "If your antenna
gets the local PBS channel, for example, it will get
all the digital subchannels".
Which may be true for
HD Radio technology, but is not the case for DTV.

Comments Welcome!

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Janitor Tzap
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Post by Janitor Tzap » Wed May 21, 2008 1:29 pm

Just and update on the RCA DTA 800B Convert boxes.

If you are still using DirecTv's Older RCA Satellite Receiver Boxes.
You'll find that the remote control signals to operate the Receiver Box.
Will also operate the Converter Box, and vise-versa.

Thus, you press the ON/OFF button from either remote, and you turn on both units.

The only thing I've done to work around the problem.
Is too go to one box and press the ON/OFF button.
Putting them out of sync with each other.
So now when you press the ON/OFF button.
The one box turns off, and the other turns on.

Only problem is that the stupid Converter Box gets confused from time to time.
So, I have to re-do the work around.:mad:
Also, it has been dropping the audio from time to time as well.
Have to shut off the box, or do a channel rescan to get it back.:mad:

{This is an improvement over analog TV?} :?


Signed: Janitor Tzap

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CeaSaR
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Post by CeaSaR » Wed May 21, 2008 2:03 pm

{This is an improvement over analog TV?}
I don't understand this either. At least with Analog you could recieve the
signal and still see/hear the programming, albeit noisy on both accounts.
With Digital, if the signal is corrupted in any way, all you see is a nasty
pixelated bunch of garbage on the screen. AND no sound! This even
happens on our wonderful Cable System around here.

I guess that's the price of progress in today's digital world - or maybe the
content providers (Hollywood etc.) want their DRM. Wouldn't surprise me.

CeaSaR
Hey, what do I know?

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