Mysterious channels appear in the lineup

Post by Ray K
I have a Samsung connected to a rooftop antenna, pointed toward NYC,
which is about 40 miles north of my central New Jersey home. Normally,
if I press the Channel + button, the TV goes from one active channel to
the next higher one. For example, after channel 7.3 should become 9.1.
But now channel 8.102 appears between them, with the message Mode Not
Supported in a blue box on a black background. When I press the Info
button, it says 16:9.
Similarly, between channel 31.4 and 41.1 channel 36.5 mysteriously
appeared. No message, but a faint gray rectangle in the 4:3 ratio. When
I press the Info button, it says 480i, 4:3.
I have not done an automatic channel scan lately. Similar "phantom"
channels, with different numbers, have appeared before. I can use the
remote to remove them and they stay removed.
Where are they coming from?
Thanks
RK

Far away.

DX hobbyists are known to look between local channels for TV channels
that can be hundreds or thousands of miles away. Brief and unusual
atmospheric conditions can channel (sorry!) the waves from huge
distances.

There have even been reports of reflections of distant signals from
meteor trails. Those conditions are *very* brief :-) Enthusiast hunt
for them especially during meteor showers.

The above is just one set of ideas.

BTW, DX is radio amateur and short wave listener slang for "long
distance reception".

I don't know why your set finds them when you don't tell it to scan...

--
Gene E. Bloch (Stumbling Bloch)

LightByrd

2013-03-09 22:18:20 UTC

Far away.
DX hobbyists are known to look between local channels for TV channels
that can be hundreds or thousands of miles away. Brief and unusual
atmospheric conditions can channel (sorry!) the waves from huge
distances.
There have even been reports of reflections of distant signals from
meteor trails. Those conditions are *very* brief :-) Enthusiast hunt
for them especially during meteor showers.
The above is just one set of ideas.
BTW, DX is radio amateur and short wave listener slang for "long
distance reception".
I don't know why your set finds them when you don't tell it to scan...
--
Gene E. Bloch (Stumbling Bloch)

Gene...
That atmospheric phenomenon, caused by solar flares which alter the
ionization of the ionosphere, is called "skip".
From Toronto, I once talked to someone in Italy using a 12 watt SSB
transceiver.
The radio waves hit the ionosphere and bounce back to earth at random
locations.
Since most TV today is in the UHF band, I am surprised, since the higher the
frequency, the more directional the signal path.
Guess it still happens though...

--
Best Wishes,
Richard Harison

Gene E. Bloch

2013-03-10 00:19:48 UTC

Far away.
DX hobbyists are known to look between local channels for TV channels
that can be hundreds or thousands of miles away. Brief and unusual
atmospheric conditions can channel (sorry!) the waves from huge
distances.
There have even been reports of reflections of distant signals from
meteor trails. Those conditions are *very* brief :-) Enthusiast hunt
for them especially during meteor showers.
The above is just one set of ideas.
BTW, DX is radio amateur and short wave listener slang for "long
distance reception".
I don't know why your set finds them when you don't tell it to scan...
--
Gene E. Bloch (Stumbling Bloch)

As I understand it, skip only applies to the HF bands, not VHF & UHF.
The V/UHF phenomenon is more like odd-ball atmospheric conditions that
create what amounts to a (short-lived) wave guide.

But this article

http://en.wikipedia.org/wiki/TV_and_FM_DX

contradicts me. It also mentions another DX trick: moon bounce. Cool.

Meteor scatter, of course, is not the same thing.

--
Gene E. Bloch (Stumbling Bloch)

Gene E. Bloch

2013-03-10 00:55:26 UTC

Far away.
DX hobbyists are known to look between local channels for TV channels
that can be hundreds or thousands of miles away. Brief and unusual
atmospheric conditions can channel (sorry!) the waves from huge
distances.
There have even been reports of reflections of distant signals from
meteor trails. Those conditions are *very* brief :-) Enthusiast hunt
for them especially during meteor showers.
The above is just one set of ideas.
BTW, DX is radio amateur and short wave listener slang for "long
distance reception".
I don't know why your set finds them when you don't tell it to scan...
--
Gene E. Bloch (Stumbling Bloch)

As I understand it, skip only applies to the HF bands, not VHF & UHF.
The V/UHF phenomenon is more like odd-ball atmospheric conditions that
create what amounts to a (short-lived) wave guide.
But this article
http://en.wikipedia.org/wiki/TV_and_FM_DX
contradicts me. It also mentions another DX trick: moon bounce. Cool.
Meteor scatter, of course, is not the same thing.

OTOH, this site indeed justifies my initial remarks. I should have
looked longer before posting :-)

http://en.wikipedia.org/wiki/Tropospheric_propagation

There are others.

It is true that my "wave-guide" analogy is possibly a bit off, but only
a bit. E.g., see this:

http://en.wikipedia.org/wiki/Atmospheric_duct

--
Gene E. Bloch (Stumbling Bloch)

Gene E. Bloch

2013-03-10 01:01:25 UTC

Far away.
DX hobbyists are known to look between local channels for TV channels
that can be hundreds or thousands of miles away. Brief and unusual
atmospheric conditions can channel (sorry!) the waves from huge
distances.
There have even been reports of reflections of distant signals from
meteor trails. Those conditions are *very* brief :-) Enthusiast hunt
for them especially during meteor showers.
The above is just one set of ideas.
BTW, DX is radio amateur and short wave listener slang for "long
distance reception".
I don't know why your set finds them when you don't tell it to scan...
--
Gene E. Bloch (Stumbling Bloch)

As I understand it, skip only applies to the HF bands, not VHF & UHF.
The V/UHF phenomenon is more like odd-ball atmospheric conditions that
create what amounts to a (short-lived) wave guide.
But this article
http://en.wikipedia.org/wiki/TV_and_FM_DX
contradicts me. It also mentions another DX trick: moon bounce. Cool.
Meteor scatter, of course, is not the same thing.

OTOH, this site indeed justifies my initial remarks. I should have
looked longer before posting :-)
http://en.wikipedia.org/wiki/Tropospheric_propagation
There are others.
It is true that my "wave-guide" analogy is possibly a bit off, but only
http://en.wikipedia.org/wiki/Atmospheric_duct

OK, last post :-)

This site is to my mind fairly informative, and mentions a few different
phenomena that cause DX - yours and mine, inter alia (so we're both
right).

http://www.dxinfocentre.com/propagation/tr-modes.htm

You do have an advantage over me, in that you can ignore my posts in
this subthread, if you like ;-)

Anyway, I always like to learn a bit more, and that happened here.

--
Gene E. Bloch (Stumbling Bloch)

LightByrd

2013-03-15 18:41:25 UTC

Far away.
DX hobbyists are known to look between local channels for TV channels
that can be hundreds or thousands of miles away. Brief and unusual
atmospheric conditions can channel (sorry!) the waves from huge
distances.
There have even been reports of reflections of distant signals from
meteor trails. Those conditions are *very* brief :-) Enthusiast hunt
for them especially during meteor showers.
The above is just one set of ideas.
BTW, DX is radio amateur and short wave listener slang for "long
distance reception".
I don't know why your set finds them when you don't tell it to scan...
--
Gene E. Bloch (Stumbling Bloch)

As I understand it, skip only applies to the HF bands, not VHF & UHF.
The V/UHF phenomenon is more like odd-ball atmospheric conditions that
create what amounts to a (short-lived) wave guide.
But this article
http://en.wikipedia.org/wiki/TV_and_FM_DX
contradicts me. It also mentions another DX trick: moon bounce. Cool.
Meteor scatter, of course, is not the same thing.

OTOH, this site indeed justifies my initial remarks. I should have
looked longer before posting :-)
http://en.wikipedia.org/wiki/Tropospheric_propagation
There are others.
It is true that my "wave-guide" analogy is possibly a bit off, but only
http://en.wikipedia.org/wiki/Atmospheric_duct

OK, last post :-)
This site is to my mind fairly informative, and mentions a few different
phenomena that cause DX - yours and mine, inter alia (so we're both
right).
http://www.dxinfocentre.com/propagation/tr-modes.htm
You do have an advantage over me, in that you can ignore my posts in
this subthread, if you like ;-)
Anyway, I always like to learn a bit more, and that happened here.
--
Gene E. Bloch (Stumbling Bloch)

It's nice to be right -- even better to be in agreement!

--
Best Wishes,
Richard Harison

Rick

2013-03-16 22:29:00 UTC

Far away.
DX hobbyists are known to look between local channels for TV channels
that can be hundreds or thousands of miles away. Brief and unusual
atmospheric conditions can channel (sorry!) the waves from huge
distances.
There have even been reports of reflections of distant signals from
meteor trails. Those conditions are *very* brief :-) Enthusiast hunt
for them especially during meteor showers.
The above is just one set of ideas.
BTW, DX is radio amateur and short wave listener slang for "long
distance reception".
I don't know why your set finds them when you don't tell it to scan...

An amazing surviving record of a piece of prewar transatlantic TV.

'BBC Television received in New York 1937'.

meagain

2013-03-08 15:16:03 UTC

I have a Samsung connected to a rooftop antenna, pointed toward NYC, which is about
40 miles north of my central New Jersey home. Normally, if I press the Channel +
button, the TV goes from one active channel to the next higher one. For example,
after channel 7.3 should become 9.1. But now channel 8.102 appears between them, with
the message Mode Not Supported in a blue box on a black background. When I press the
Info button, it says 16:9.
Similarly, between channel 31.4 and 41.1 channel 36.5 mysteriously appeared. No
message, but a faint gray rectangle in the 4:3 ratio. When I press the Info button,
it says 480i, 4:3.
I have not done an automatic channel scan lately. Similar "phantom" channels, with
different numbers, have appeared before. I can use the remote to remove them and they
stay removed.
Where are they coming from?
Thanks
RK

Possibly Last time you scanned you picked up some "low power" stations
that just had a place keeping (blank screen) going. Do any of these
appear to be from educational institutions?

--
www.BoltonAccess.TV

Jim Wilkins

2013-03-08 18:09:53 UTC