can digital get picture if analog TV is weak?

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. :-)

One designed specifically for reception of digital transmission frequencies, in your area. One with a suitable feed co-ax and also suitable connections etc.

Sure they do, as defined.

So you can view Ch31/community access TV? :-(

MrT.

Reply to
Mr.T
Loading thread data ...

course,

using

end

handling

I live in a strong signal area, and I always find the reverse to be true.

MrT.

Reply to
Mr.T

...... drop-outs. :-)

MrT.

Reply to
Mr.T

This

Impossible while they are still transmitting analog signals on those frequencies. AFAIK, SEVEN transmits digital on ch6, NINE on ch8, TEN on ch11, and ABC on ch12 in most capital cities.

MrT.

Reply to
Mr.T

Thanks Stu, your a lone voice in the wilderness. People are gulable when it comes to this sort of thing, Just say "digital" and the price goes up, The intrest intensifies, and people cue up to be ripped off.

The link that Phil posted [Hi Phil] is a typicial example of the rip-off machine in action. About the only thing you might need is a better cableing system , In other words swap the cable for a length of RG 6, thats worth 30 cents a meter and people like Dick Smith sell for $3 a meter. Cos it's digital cable. and your away. bassett

Reply to
bassett

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.

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,

examples please

Not in country area's mate. bassett

Reply to
bassett

"bassett" "Stuart"

** The link I posted was for the EXACT SAME ANTENNA

- you bloody half- wit !!

formatting link

........ Phil

Reply to
Phil Allison

You really don't get it do you "Basset"?

I agree with MrT. How often you get drop-out's effectively determines how good or bad a digital TV reception you've got. Lots of drop-outs is certainly "worse" than no drop-outs. Yes it's still digital, but that's not the point.

*yawn*

You really don't get it do you "Basset"? A "digital" antenna designed just for the digital TV bands of interest is certainly a different "type" of antenna than say an analog Yagi or rabbit ears.

*yawn* Give up dude.

Dave.

Reply to
David L. Jones

"bassett"

** This next bit is hysterical .......
** Wow - not even with 200 metres of co-ax after the antenna ....
** Hmmmmm - just like the TV ad says :

Its the BITS that John West rejects that make the TUNA work best ....

** ROTFL !!!..

Everyone knows that 2 out of 3 ain't bad !!!

** The connection with " pixies " here is getting very strong.

" bassett " is chasing them all over the damn place !!!!!

....... Phil

Reply to
Phil Allison

Lone voice? I said that earlier in the thread:

formatting link

The link Phil posted (which was my original link in an old thread) is the exact "digital band" antenna being talked about! It is *not* an example of "the rip-off machine in action", it is a log-periodic digital band antenna, designed just for the digital channels.

Let me know your PayPal address so I can send you a dollar so you can buy yourself a clue.

Dave.

Reply to
David L. Jones

Although as Bassett has said, there are a lot of rip-offs out there and certainly a lot of misinformation about digital antennae systems, there is some info which is correct. For example - Anyone from the good old analogue days (circa 1980's) will recall the Hill's Telray series VHF antennae. When I went across to digital very early in the piece my antenna system consisted of a Telray TL4, a Hills Band 4 UHF antenna (20 or more elements - can't recall the model number) and a diplexer hooking the two together, fed by double shielded coax similar but not the same as the current RG6. The combination worked quite well for analogue not withstanding the unfixable ghosting problems in my reception area.

On purchasing a STB I noticed reception of ABC digital (VHF ch 12) was very flaky and the signal level almost down in the "red" compared to the other digital channels which were way up the other end of the scale. It turned out that after pulling up the specs on the TL4 that it performs very well to Ch11, where thereafter the gain of the antenna takes a steep dive. This along with the original diplexer really knocked the crap out of the signal level at those frequencies. Replacing the TL4 with a Hill's DY10 and upgrading the diplexer totally solved the problem.

There is however a bit more to the story. Replacing the diplexer also meant replacing the short lengths of cable between the antennae and the diplexer with F connectors (replacing saddle clamp connections) and of course fitting the downlead with an F connector too.

It is recognised within the industry that albeit the digital signal is relatively robust it isn't completely immune to interference. Whereas with analogue we put up with the odd bit of noise on the picture, digital can be affected to the point of significant pixilation and muting of the audio. This can be subjectively more annoying than watching a noisy analogue picture. Antenna downfeeds and distribution cables installed in close proximity to power cables, fluoro lighting and some other electrically "noisy" equipment can degrade the quality of the received digital signal leading to pixilation and in some cases muting of the audio. Using a good quality tri or quad shielded coax and sensible placement of the cable(s) in relationship to other electrical services can make all the difference to the quality of the signal the TV or STB receives.

Unfortunately there are a lot of legacy analogue antenna systems out there. Some suitable for digital, some not. Blocks of flats with amplified distribution systems designed purely for analogue are typically a nightmare for digital as only the designated analogue channels are amplified and equalised, leaving the intervening digital channels with level and equalisation problems. Likewise there are some houses out there with a good old ch2, 7, 9 antenna with a 300 ohm balance ribbon feed. With the exception of SBS they are probably getting by with adequate analogue reception but lets face it, the antenna has probably seen 30+ years of life and is well and truly overdue for replacement. The sad part is the owner will be quite prepared to fork out $4k on a new plasma or LCD TV but won't spend a couple of hundred bucks getting the antenna system replaced.

Cheers, Alan

Reply to
Alan Rutlidge

On Aug 7, 1:33 pm, "Alan Rutlidge" analogue we put up with the odd bit of noise on the picture, digital can be

Unfortunately I'm still having issues with interference after trying all the usual recommendations:

- replaced all my cabling to quad shield RG6 and F connectors, even from the wall outlet to the TV.

- switched to a new higher gain antenna to get better signal strength

- checked my mains earthing

- connected the antenna to its own earth stake.

- made sure the cabling was not near any other cables

- and finally switched antenna's yet again to a log-periodic type (that reduced the number of drop-out's very significantly)

But alas I still get the occasional drop-out due to some external influence (not local appliance switching in my house, although that does it too), and of course due to MrMurphy it's always right at a key point in a show. Losing the picture for a second is ok, but the audio pop is really annoying.

But at least it's down to a very manageable level now.

Dave.

Reply to
David L. Jones

"David L. Jones"

** Some STBs produce occasional huge audio pops ( like the TEAC DVB-300) while others are near silent when a burst interference causes the pic to freeze.

However, an audio pop could be nothing to do with the STB but rather a result of the same RF burst getting into the audio earth wiring due to the existence of ground loops.

Try installing an antenna isolator before the STB.

....... Phil

Reply to
Phil Allison

Albeit I think I've just about solved all my digital TV reception issues, it is still far from perfect. :-( AFAIK in Perth the digital transmitters are not running at full power (apparently to reduce interference) to older analogue sets and analogue VCRs with less than perfect tuners. When and if the analogue services are shut down the digital transmitters will be allowed to run at full power. This should improve the signal to noise ratio and hopefully resolve some reception problems. Having said that, too much signal level can be a problem as well. Attenuating the signal at the wall outlet will not only reduce the signal level to an acceptable one, but reduce the interfering noise by the same amount.

The problem with RF is it isn't a totally predictable science. Take mobile phone coverage as an example. There are too many variables which influence the propagation of the signal to be totally sure of the outcome. Add external interferences (natural and man made) and you have a cocktail of situations which can lead to problems. And of course there are the variations in tuners from very good to bloody woeful. No wonder Joe Average is confused. If you haven't already visited the DTV forum it might be worth your while for advice (both good and bad).

formatting link
It isn't the definitive answer to all your questions, but at least it's a start and there are some knowledgeable bods there who are willing to share there expertise.

Cheers, Alan

Reply to
Alan Rutlidge

digital

Funny then that I have a digital STB and a digital PVR that both give picture drop-outs on occasion. And I am in a good signal area. My friend who also has a STB and PVR suffers

*far* worse problems.

I suggest it is YOU who has no idea!

Or you are! :-)

Pity you can't read the definition given, or simply can't understand it. But I am indeed envious if you live in a rural area and *never* get any signal problems, especially with an "old coat hanger"! :-)

Others have already posted examples. Have you looked at those yet?

MrT.

Reply to
Mr.T

Save your dollar, he wouldn't know where to buy one.

MrT.

Reply to
Mr.T

Try raising or lowering the antenna by 300mm or so. Multipath reflections might be causing some of your problems.

Reply to
dmm

Tried that, no joy.

Thanks Dave.

Reply to
David L. Jones

I've tried 3 different STB's and all are pretty much the same with the interference and the popping. Guess I didn't get lucky.

Will do, thanks Phil. A quick search doesn't turn up much though, know where I can get one?

Thanks Dave.

Reply to
David L. Jones

"David L. Jones" Phil Allison

** K-Mart used to sell 'em.

Not impossible to wind your own iso-balun.

....... Phil

Reply to
Phil Allison

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.