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micky micky is offline
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Default Part 2: alternative to antennaweb, Curious channel redirection.

On Wed, 01 Apr 2015 22:41:58 -0400, micky
wrote:

I'm still working on my antenna amp, but it gave rise to a couple more
questions.

I looked at antennaweb.org and it is still good, but the format has
changed. There is another webpage that also shows what tv stations are
within range and what direction they are. Does anyone remember the
name?


Fooltv.com is one of the other webpages that shows tv stations near a
user-chosen location (in the USA, iirc)

But it shows stations quite a bit farther away even when there is,
according to the webpage, no chance of getting the station where I am.
It even has a special color for stations the user can't get, red.

But I never believe what people tell me, and I figure the signal might
be carried on the wings of doves, farther than the webpage anticipates.

So I noted all the stations and tried them.

Also, antennaweb shows station WMDE, on VC 36, RF channel 5, only 45
miles from me at 128 degrees, ,on the Eastern Shore of Maryland, not far
from Delaware. But when I tune to channel 36,1 and I've done this 6
times, it displays a tv show for a moment, and then switches to virtual
channel 5.1 where it displays the same program although this time, it
keeps showing it. . Channel 5 is a DC station, WDCA with an RF of 36.


It turns out the effect is duplicated at other stations.

If I tune to channel 27, a picture blinks on the screen, with channel 27
still noted in the upper right corner of the screen, then t he screen
goes blank for part of a second and reappears with the same picture,
except that now channel 26.1 is displayed in the uppper right corner..

The same thing happens for 5 pairs of stations, starting with the one
above:

Thanks Rev. and Jeff for the information on what TV signals reach what
locations. It turns out TVfool.com shows a lot more channels for my
location in NW Baltimore than do antennaweb.org or the one you suggested
Rev. but at the same time, tvfool points out I probbably can't get
many of them. They even have a special color for all the stations I
can't get, red!

But it's my nature that I tried them all anyhow and I found an
interesting phenomenon.

Of the 40 or so virtual n.1 channels** I entered with my remote
control, 5 or 6 of them (depending on how one looks at it) seem to get
redirected to another virtual channel that seemed to be showing the same
program! **That is, only main channels, like 11.1. I didn't
try this with subchannels 11.2 or 11.3.

Here is a list. I entered the number in the left column (without ".1")
and after the screen blinked once or twice, it displayed the virtual
channel in the right column, including displaying the number, such as
67.1, in the upper right corner of the screen, as my DVDR does when I
tune to a new station.


Entered Destination
VC VC
27 === 27.1
29 ==== 67.1
34 ==== 66.1
41 === 24.1
48 === 4.1 plus
36 ==== 5.1 (the one from the previous post)

VC stands for virtual channel, RF for radio frequency (the actual
frequency, not the channel number now assigned to it.)

So WMDE is VC 36, RF 5, and
and WDCA is VC 5, RF36. the opposite.


Like this pair, 36 and 5,
VC27 is RF27.1
VC67 is RF29.1
VC66 is RF34.1
VC24 is RF41.1
VC47 is RF22 .1
VC4 is RF48.1

And the opposite is true too:
RF27 has VC 27.1
29 has VC 67.1
34 66.1
41 24.1
48 4.1
and 27 27.1

(When no virtual channel is listed, it's the same as the RF channel.)

Does this coincidence have anything to do with what happens.


Since there are 6 of them (or is it only 5?), it must not be a
coincidence not only does m point to n, but in each case, n points to m.

But what is the point of it all? Certainly not all VCs point to an
RF which, if the RF is found in a VC table, it points to the RF which
was the original VC, right?

Or said another way Where m and n are integers 67 or less:
Certainly not every VCm points to an RFn which, if the RFn number is
found in a the VC column and called, say, VCn, not always does it point
to RFm where VCm and RFm are the same absolute number. right?

Do I need to ask this more clearly?

Of if you understand me already, is there a name for what I've pointed
out? So I can go read about it.


But WMDE must have been working somewhat, in order to go to 36 and
learn the RF numberl 5, or is that the VC channel 5.

Have any of you come across something like this before.

Thanks.