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"Vey" wrote in message
nk.net...
Arfa Daily wrote:
"Vey" wrote in message
ink.net...
wrote:
There are indoor ones, I'm having a hard time seeing how these could
work. I have an albiet old, functioning outdoor up in the attic. It
splits in two, then into four off the amp downstairs. The amp is quite
old.

Now I have seen ATSC at work, where the reception is worse. I asked the
boss and he told me there are two amps. They were installed decades
ago, and are of course not "HDTV ready", so I am assuming such a thing
will actually work.

Now I want to feed into a PCI ATSC tuner in a computer, and I know
these things need a helluva lot of signal. Even on NTSC it is snowy,
and can't aquire any ATSC channels. I know they are here, about thirty
of them.

Is it even worth a try to throw in a really good amp with a high MOL
and let everything else be taps instead of split ?

And, if this doesn't get us ATSC, or acceptably ATSC, should I even try
an indoor ? On NTSC I expect notoriously crappy reception, but then
multipath etc affect this differently. Do the indoor ATSC antennas work
even decently ?

The added problem is that it is a PCI card. There is simply not enough
room for a high gain front end. I understand this and figured I might
have to deal with it, but I thought our regular antenna would at least
get something. I even fed the whole output of the amp to it, still no
ATSC. NTSC was still snowy also.

This card was not very expensive, I have no problem feeding it with
whatever it needs, but I do not want to go buy the wrong thing and have
it not work. I want the first thing I buy to work.

If it matters, I live in Cleveland Ohio, near Harvard and Denison.
There is a cliff almost directly to the south of me, towards Parma,
where the towers are. My current antenna recieves all local channels
acceptably. If it is purely a matter of signal strength, perhaps all I
need is a kickass amp.

Thanks for any help on this. I would like to see it work before the
warranty runs out of course.

JURB

Here is the big "secret" of all time. There is no difference between an
old analog antenna and a new "digital" one other than one is old and one
is new. Make sure that you clean up the contacts, and run new wire (I
like the quad shielded cable from Radio Shack) to the antenna. That's a
good idea no matter what you do.

I have several PC Tuner cards. Some are analog, one is HDTV. All have
the same problem, they need a good, clean, strong signal because they
have been desensitized. PC's make a lot of RF noise, so the cards are
desensitized to avoid picking up that noise. Mast mounted pre-amps can
help amplify things for both, but sometimes they can make the digital
signal worse.

Having a mountain between you and the transmitter could be a problem.
Where the analog signals would "bend" around it (and maybe you would see
a shadow, or double image) digital doesn't bend.

Keep fiddling.

Unfortunately, your contention that there is no difference between
analogue and digital antennas, does not hold up this side of the pond.
Many digital multiplexes caried by UK transmitters, are split from one
end of the UHF band to the other, at the same site. Thus, if you point an
existing group A antenna at an existing group A analogue site, and then
try to receive the digital multiplexes from that site, you may well find
that there's nothing like as many channels there as you expect, as you
are missing a whole multiplex up in group C. So the big secret of all
time over here, is no matter what the fancy TV adverts tell you about how
wonderful digital is, and all you've got to do is plug in your STB or
digital-ready TV to get it, in many parts of the country, it simply isn't
true, and you're going to be up for a new 150 quid ($240) wideband
digital antenna. Just to cap it off, most of these are the ugliest
crossed element antighost ( why though ? I thought this digital TV was
supposed to be immune to multipath ) or multi arm log periodics that
you've ever seen. Twice the size of a nice little 10 ele analogue.

There is no reason that digitally modulated signals should be any less
susceptible to bending around objects, than analogue ones, as far as I am
aware. This assumes of course that they are in the same band. In actual
fact, I think that the bending around mountains usually takes place
across the top of them when they have a sharp ridge, and is known as
'knife-edge refraction' but I may be wrong there. As I recall, this
effect is better established at VHF than UHF.

Arfa

Good thing the poster mentioned ATSC rather than DVB, so we wouldn't get
confused, eh? First sentence, second paragraph.

Yes, but you made the blanket statement that there is no difference between
digital and analogue antennas. I made the statement that there is, and
qualified that with " this side of the pond " followed by a reference to UK
transmitters, lest anyone over here reading your statement, should be misled
by it ...

Arfa