On Jan 20, 12:28*pm, "bg" wrote:
mm wrote in message ...
Before the advent of mandatory digital over-the-air TV, it was said
that the picture would be near perfect, and that there woudl be no
ghosts. * Tonight I saw one, for a full half hour if the scene had the
right kind of lines, including vertical lines.

From the beginning I had doubts about the claim there would be no
ghosts. *I gleaned or understood that, aiui, if a ghost signal was
less than, say, 50% as strong as the direct signal, and the direct
signal were 0, the electronics would "round down" and output a zero.
If the direct signal were 1 and the ghost was less than 0.5 and more
than zero, or more than -0.5 and less than zero, the sum might be 1.5,
but the electronics would interpret that as a 1.

But that didn't account for every situation. *What if the ghost signal
was 0.6 the strength of the direct signal and the direct signal was a
zero? *Now, although I've never seen it discussed (and I do read a
bit) I presume there are 3 signals making up the OTA video signal, and
I'm ignoring that for now.

Anyhow, for the first time in 9 months, with no changes to the tv
wiring of my house, tonight I saw a ghost on an OTA tv show. * On
channel 7.3 in Wash. DC, and I live about 30 or 40 miles north of the
transmitter. *A black and white show, The Rifleman, with Chuck
Connors, from the 60's I think, but maybe the 50's.

I don't know from where the reflection could be coming. *There is a 7
story building about 100 yards behind me and to the left (wrt channel
7) but that's not far enough away, is it, to account for 1/8" or 3/16"
ghost displacement on a 19" tv? * *Woudln't any ghost from there be a
small fraction of a millimeter from the main image?

Could the ghost be in the coaxial connection between my TV tuner (a
DVDR) and the tv. *There is 15 feet of co=ax, an RF amp/splitter, 8
more feet of co-ax, a splitter, another RF amp, another splitter, 30
feet of co-ax, then another splitter, then 10 more feet of co-ax. * If
that were the source, it wouldn't be attributable to a digital signal,
but I don't think those lengths are sufficient to account for a ghost
1/8" from the main image, are they?

They also didnt' mention, said otherwise though I forget the words
they used, that there would be checkerboard interference. *I get that
a lot on several stations, especially the ones that are 30 or 40 miles
away.

How much tv did these people watch before they made their false
claims? * Were they only a mile from the transmitter in rural Kansas?

Does anyone know their names or email addresses so i could tell them
how foolish they look?

I get two new stations I like with digital, so I'm not angry. (I
wouldn't be anyhow.) I just think they make themselves look stupid
when they make false claims that they should have known better than to
make, and to an extent, the impression this leaves spills over on to
other "experts" and "scientists", in other fields.

I've not had ghosting, but in the beginning of the transition, I used to get
something that looked like the reds were shifted, like bad convergence. The
shift changed, so that the red picture would sort of float around it's
target. It might have been a combination of the broadcasters working out the
bugs, and me working out the antenna, because my picture has been flawless
for about 6 months. I did cut way back on my signal level by removing a
distribution amp and padding the antenna output.- Hide quoted text -

- Show quoted text -

If it was a black and white picture, it could be there were some
artifacts caused by the film to video conversion. Did you check any
other sets or neighbors' tvs to see if they saw the same thing.