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can digital get picture if analog TV is weak?

This much is correct.

Total rubbish. In a marginal area a GOOD low noise amplifier at the Antenna will give better reception as with any other form of transmission system. It must have a very low noise figure and enough gain to make up for any feedline loss and splitter losses between the antenna and the receiver. Lots of gain is not better but an amplifier can make an otherwise unreceivable signal watchable. There is a requirement that there be a carrier to noise ratio of at least 19+ dB at the antenna to receive DVB COFDM transmissions with a 23Mb/s data rate.

bassett also wrote....

This is the most hysterically funny explanation of how digital works that I have ever seen. It just proves how clueless bassett is about things digital.

Firstly there are not 4 layers of anything transmitted. The transmitted signal used for terrestrial transmission in Australian standard digital consists of either 2K (some 1700 carriers) or 8K (some 6000 carriers) in quadrature each modulated with 64 QAM (Quadrature Amplitude Modulation) giving a stream data rate of 23.052768 Mbits/S with our normal FEC and guard interval. The use of FEC is a method of transmitting extra bits with the wanted stream MPEG data to make it more rugged. The FEC is not in the receiver it's transmitted as extra data bits in the stream that allow reconstruction of damaged packets in the receiver. What 3/4 FEC means is that for every 3 actual bits of data an extra bit is transmitted as FEC. In other words for every wanted 3 bits of information

4 are transmitted. NOT 4 signals only one with extra information.

Small corruptions of the stream data will not cause pixellation as the FEC allows the damage to the data to be corrected and no visible degradation is seen. If the data is corrupted more than the FEC being transmitted is capable of correcting then either pixellation will occur or the decoding will fail.

If high values of FEC are transmitted such as 1/2 where every bit in the stream is transmitted twice there is obviously more correction available but at the penalty of loss of wanted data rate.

In particular on satellite transmissions FEC values of 1/2, 2/3 or 3/4 are usually used especially 1/2 or 2/3 where small dishes are being used for reception.

The more robust forms of FEC are not generally used in terrestrial digital transmissions as there is a need for the highest possible data rate to be able to transmit HD and SD at once in the same stream.

Reply to
100246.2055
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Whatever,, But it strange that all the experts are having trouble and all the dickheads have perfect reception. bassett

Reply to
bassett

Maybe something has escaped me here, but I was under the distinct impression that the FEC operated on the data stream, implying the demodulated signal. That being so, how can it be "examine the signal long before it reaches the tuner"? So no I would not agree.

Reply to
keithr

Hi John, long time no see. Not since the old avtech days.

Reply to
keithr

May be on to something there :-) I have an old antenna that has been in use for 15 years, with a couple of TVs. (roof mounted, and I am approx 15 Kms from Mt Cootha TV towers) Bought a 101cm Samsung LCD two months ago, and set it to auto tune in the stations, the tuner "failed" to select any analogue stations, but then searched in digital mode and tuned in all the stations with excellent reception. I also have foxtel, so no problems here :-) btw, the Samsung is great.

Reply to
Sunny

At least you now realise you are a d*****ad. Anyone can get lucky, but there is no evidence that "all" the other dickheads have perfect reception.

MrT.

Reply to
Mr.T

bassett

I think it's more of a "Dont confuse me with the facts.. my minds made up" situation Bassett!

Reply to
100246.2055

"bassett"

** Peeeeeeuuuuuueeeeeeeee !!!

" bassett " just did a very smelly fart ........

Outside, doggy - outside right now .....

....... Phil

Reply to
Phil Allison

There is and lots of it but it is anecdotal

Reply to
a t e c 7 7

the

there

I fail to see how any unspecified anecdotes can prove ALL dickheads have perfect reception, but I will accept you have just provided one example at least.

MrT.

Reply to
Mr.T

trying to make a funny point again I see T , and failing

Reply to
a t e c 7 7

So, we could say that your 15 year old antenna, is a digital only antenna, seeing as it failed to tune any analogue signals.

Now all the experts will tell you that, the Tuner was digital, so why would it tune analogue. but the facts are the facts, and your watching your Samsung, and as you say there good shit. Well done,

And by the by, our know-all mate, with the digital antenna link, I suggest you check out the Strathfield catalogue, [back page] It shows the dead spit of your 32 element UHF / VHF antenna. $59.95. No talk about it being digital AT ALL

bassett

Reply to
bassett

Never mind, you see that's the difference between a dichhead and a f****it, But you will learn that when you reach the age of six.

bassett

Reply to
bassett

Trying would be the operative word "atec" He trying all right, Bloody trying. I think someone pissed in the puddle he was playing in. bassett

Reply to
bassett

This thread now degenerates down to Phil's level, Do not pass go, do not collect 200, go back to Aus Hi-Fi, and annoy no-one bassett

Reply to
bassett

Who told you then?

MrT.

Reply to
Mr.T

Who told me what, "Petal"

Reply to
bassett

So, you obviously never worked in the industry!

With digital signals, if the signal is on the edge, it will start to give pixellations. This is because parts of the data packets can be missing due to the noise level being too high in relation to the weak signal. As for antennas, they can be very sophisticated with distribution amplifiers and etc. I am not talking about a simple pice of wire, which is not realy a very high performance type antenna!

Below is an example of many instances where TV pixelation has occurred due to poor reception.

________________________________________________________

From:

formatting link

Now to the problems: TV Pixelation: I had a tech tell me that the TV signal strength was borderline and that would potentially cause some pixelation. There was a ticket open to look into this since June 3rd and I have been told to call weekly as long as the problem persists. The real problem is that this will affect all 24 people who share a fiber termination point with me ..but because I am the first they are not getting enough complaints to come out and fix it yet. Its a minor annoyance and we encounter maybe 15 seconds of it a night and I have yet to see it once on a recorded program.

Outage: 3 days after they installed the service ..it stopped working ..not everything mind you just the Phone and internet. So I call tech support ..and I am routed into an IVR system that does the diagnostic for you then opens a ticket ..no option for a human being. I was told I should have a fix by 6 hours later (8pm on a thursday).

Well 4 hours later I call back to check ..still stuck in the IVR system I am told the ticket won't be fixed for 24 hours. So the following day from work I connect to Verizons web support chat, where I am told that the box on my house( a module in the NID) is not communicating correctly. Long story short ..no tech on Friday either but I got angry enough to get through to a human being on the phone (via cell of course as the home phone is dead) and got promised a tech first thing Saturday morning. So first thing Sat ..tech shows up, he replaces a module inside the NID ..calls in to activate it ..and POOF problem fixed.

___________________________________________________________

--

JANA
_____


"bassett"  wrote in message 
news:46b7dd0c@dnews.tpgi.com.au...

"Mr.T"  wrote in message
news:46b6cd74$0$7087$afc38c87@news.optusnet.com.au...
>
> "bassett"  wrote in message
> news:46b523a8$1@dnews.tpgi.com.au...
>>   With  digital there  is  no  such  thing as good or  bad,  You  ether
>> have a  signal or  you  don't.
>
> Crappo. I consider no drop-outs/pixelation to be "good" and *lots* of
> drop-outs/pixelation to be "bad".
> No signal/picture at all would be "really bad" of course. :-)

  I  don't think  you have idea,  just  how  digital  works.  With  digital
you  get a picture or  you  don't. it's that  simple.  No  snow,  no noise,
etc.  also  there is  no  need  for   a mast head  amp,  EVER.  regardless
of  what  your  installer  might tell you.
  Digital   works  with a  multi-layer of  signals,  once the  signal is
transmitted , it's  picked  up  by the   forward error  correction, [FEC]
in the receiver  and the  best  signals are  selected  and  sent to the
tuner   Most  common   configuration  is  3/4.  From the  four  signals
sent  it  selects  three,  If it  can't  find  three  it  simply  shuts
down .  You  might  get  some  pixallation  in heavy  rain,  this  happens
simply  because  for a  few  millie-seconds  it  can't   access  the  signal
requirements,  If  it  continues  it  simply  shuts  down, until  it  can
work as  it  should.
>
>>  *** Define  "Digital"  antenna.
>
> One designed specifically for reception of digital transmission
> frequencies,  in your area. One with a suitable feed co-ax and also
> suitable connections etc.

  There is  no  differance between  antenna  types,  they  work or  they
don't. it;'s as  simple as that.   In  some  situations plan old  "rabbit"
ears will  work, or a  coat hanger,  and there's  nothing  digital about
them,

>>They  don't  exist..
>
> Sure they do, as defined.

 examples  please

>> > Once you get digital you won't go back.
>>
>>    ***   why  would  you want  too  ??????
>
> So you can view Ch31/community access TV? :-(
>
> MrT.
  Not  in   country  area's  mate.
                                                          bassett
Reply to
JANA

What in heavens name does a cable problem with Verizon have to do with AUSTRALIAN digital TV? This is an Australian newsgroup and we use DVB not ATSC which is totally different in transmission methods.

Reply to
100246.2055

*** cough **** *** cough ****

ABSOLUTE BULLSHIT. You have a signal that gives a picture but it breaks up and pixellates. I would regard that as BAD!

Reply to
Wayne Carr

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