need help understanding what is wrong with the reception of one
channel. i have an old metal antenna on the house that works great for
the strong local signals. years ago i added a small antenna that was
designed to pull in one particular local channel. it is installed on
the same pole, and plugs into a small box also on the pole that acts
as a splitter i guess. anyway, regardless of whether i am running the
signal into the vcr or the tv, all the powerful channels come in fine.
however, this other one, channel 13 (Hmmm...) doesn't come in well
unless i disconnect the coax from the tv, then very gently touch it to
the connection on the back of the tv. the improvement is dramatic,
but i'll be damned if i'm gonna watch tv this way. i don't understand
why the same connection works great for the other channels, but not
for this one. i have tried changing out the cable, using splitters,
not using splitter, directly from wall, from vcr, etc. it never seems
to come in unless i am holding the cable connection to the connector
on the tv in this very specific way. what's going on? i know this
station used to come in better, but now its crap. help. anyone?

On 19 Oct 2004 09:23:23 -0700, (mediancat) wrote:
i have tried changing out the cable, using splitters,
not using splitter, directly from wall, from vcr, etc. it never seems
to come in unless i am holding the cable connection to the connector
on the tv in this very specific way. what's going on?

Hi OM,

When you are holding the cable in its odd way (and it works just
fine), then you have happened upon an unique combination that proves
you should be able to do it right. However, the question remains,
what are you doing wrong?

Is the new antenna pointed in the right direction? Try turning it
through all 360° to see how that improves/degrades the situation.
This presumes you have all the right connections of course.

As you are using two antennas, how are you connecting them to the same
TV or VCR? As you have tried this antenna individually and still
found no happy conclusion, it would seem to be an elemental problem.

How far away is this station you are trying to get?

What kind of neighborhood are you in (city/suburb/rural)?

Are there path issues like hills?

Is this a matter of a snowy picture, or one that is broken up with
multiple images, or...?

What kind of line are you using? Twin lead (flat ribbon) or Coax
(round, thick cable)?

73's
Richard Clark, KB7QHC

mediancat wrote:
need help understanding what is wrong with the reception of one
channel. i have an old metal antenna on the house that works great for
the strong local signals. years ago i added a small antenna that was
designed to pull in one particular local channel. it is installed on
the same pole, and plugs into a small box also on the pole that acts
as a splitter i guess. anyway, regardless of whether i am running the
signal into the vcr or the tv, all the powerful channels come in fine.
however, this other one, channel 13 (Hmmm...) doesn't come in well
unless i disconnect the coax from the tv, then very gently touch it to
the connection on the back of the tv. the improvement is dramatic,
but i'll be damned if i'm gonna watch tv this way. i don't understand
why the same connection works great for the other channels, but not
for this one. i have tried changing out the cable, using splitters,
not using splitter, directly from wall, from vcr, etc. it never seems
to come in unless i am holding the cable connection to the connector
on the tv in this very specific way. what's going on? i know this
station used to come in better, but now its crap. help. anyone?

Although you've provided a good bit of detail, some questions still arise:
just 'how' do you "touch the coax to the connection?" Are you touching just
the inner conductor to the outside of the connector, or the inner conductor
to the inner connection on the connector (not allowing the ground to make
contact)? Are you touching the coax connector on the TV at all...perhaps
instead the 300 ohm (if any) connectors?

Without being a bit more specific, I doubt anyone's going to be able to help
you. For one thing, I don't understand how the two antennas are connected
on the pole in such a manner as to preclude interaction (perhaps a ch. 13
trap in series with the 'all channel' antenna before the
splitter/combiner?).

In any case, your problem is probably 'up the pole.' If it worked before, i
t should work now; unless conditions have changed. Have any tall buildings
been constructed between you and the transmitter?

My best advice would be to have the same people who installed the array (or
other competant service people) service it. It sounds like your technical
knowledge is limited, and I doubt you're going to want to climb that pole...

....or get cable.

jak

Is the new antenna pointed in the right direction? Try turning it
through all 360° to see how that improves/degrades the situation.
This presumes you have all the right connections of course.

yes, its pointed west as the guy at the station has suggested. i did
go up and rotate it through the compass points just to be sure there
wasn't a better direction for it.

As you are using two antennas, how are you connecting them to the same
TV or VCR? As you have tried this antenna individually and still
found no happy conclusion, it would seem to be an elemental problem.

in seattle, this antenna scheme is sold specifically to pull in a
station that is west of the city, when all the other local stations
are in town. so my main antenna points north toward downtown seattle,
and this smaller one, that i mounted as instructed (on the same pole)
points west. there is this small plastic box that is part of this
kit. it too is mounted to the pole. i guess it's a splitter. i plug
the little and big antennas into the box and a third cable runs down
to the house. the station is not terribly far away - it used to come
in fine, and they haven't degraded the signal. i live kind of on a
hill so i don't think a building or hill is interfering with my signal
path. when the coax connector is plugged into the tv, and all the
other stations come in, channel 13 is snowy. you can barely make out
what is going on.

Although you've provided a good bit of detail, some questions still arise:
just 'how' do you "touch the coax to the connection?" Are you touching just
the inner conductor to the outside of the connector, or the inner conductor
to the inner connection on the connector (not allowing the ground to make
contact)? Are you touching the coax connector on the TV at all...perhaps
instead the 300 ohm (if any) connectors?

i believe i am touching both pieces, ever so slightly. i tried one of
the other cables in the scheme that has a longer inner conductor - to
allow the connection of that alone, but it didn't improve the picture.
perhaps i really am only touching the gound part of the coax to the
ground part of the tv connector. that would explain why when i fully
engage the connector, the signal gets crappy. i will try some other
combinations to see if i can clarify what i am doing.


Without being a bit more specific, I doubt anyone's going to be able to help
you. For one thing, I don't understand how the two antennas are connected
on the pole in such a manner as to preclude interaction (perhaps a ch. 13
trap in series with the 'all channel' antenna before the
splitter/combiner?).

i mounted and pointed west a smaller antenna, onto the same pole as my
main antenna. there is a box on the pole as well where the two
antennas are connected and a third cable runs to the house.


In any case, your problem is probably 'up the pole.' If it worked before, i
t should work now; unless conditions have changed. Have any tall buildings
been constructed between you and the transmitter?

no new tall buildings. my hunch is that the connector for the smaller
antenna, or the part of the splitter/combination box up there that is
for the smaller antenna, is failing. all the other stations still
work beautifully.

My best advice would be to have the same people who installed the array (or
other competant service people) service it. It sounds like your technical
knowledge is limited, and I doubt you're going to want to climb that pole...

my technical knowledge is for sure limited, but i installed all this
stuff once and it worked. i guess i will be up on the roof this
weekend, taking a closer look at the small antenna connections.
thanks for the advice

On 20 Oct 2004 07:09:45 -0700, (mediancat) wrote:


Is the new antenna pointed in the right direction? Try turning it
through all 360° to see how that improves/degrades the situation.
This presumes you have all the right connections of course.

yes, its pointed west as the guy at the station has suggested. i did
go up and rotate it through the compass points just to be sure there
wasn't a better direction for it.

As you are using two antennas, how are you connecting them to the same
TV or VCR? As you have tried this antenna individually and still
found no happy conclusion, it would seem to be an elemental problem.

in seattle, this antenna scheme is sold specifically to pull in a
station that is west of the city, when all the other local stations
are in town. so my main antenna points north toward downtown seattle,
and this smaller one, that i mounted as instructed (on the same pole)
points west. there is this small plastic box that is part of this
kit. it too is mounted to the pole. i guess it's a splitter. i plug
the little and big antennas into the box and a third cable runs down
to the house. the station is not terribly far away - it used to come
in fine, and they haven't degraded the signal. i live kind of on a
hill so i don't think a building or hill is interfering with my signal
path. when the coax connector is plugged into the tv, and all the
other stations come in, channel 13 is snowy. you can barely make out
what is going on.

Hi OM,

By this I presume you live south of Kent in Auburn or Puyallup (I live
in Seattle too).

TV in this area is so ubiquitous that you should get channel 13 by
waving your....

It sounds like you are trying to put Channel 13 into the UHF connector
instead of the VHF connector of your TV. The box you speak of sounds
like a VHF/UHF combiner, and I don't hear its twin at the other end of
the line being used (a VHF/UHF separator). If you are not using or do
not watch UHF (don't watch Channel 22?) then you need a simple
combiner. However, I think that is distinctly unlikely that you would
not be watching FOX - or maybe it's WB, I've gotten so use to the
cable channel mix I've lost track of the over-the-air slots.

Anyway, this sounds like an UHF/VHF splitting/combining problem now.

73's
Richard Clark, KB7QHC

mediancat wrote in message
om...

Although you've provided a good bit of detail, some questions still
arise:
just 'how' do you "touch the coax to the connection?" Are you touching
just
the inner conductor to the outside of the connector, or the inner
conductor
to the inner connection on the connector (not allowing the ground to
make
contact)? Are you touching the coax connector on the TV at
all...perhaps
instead the 300 ohm (if any) connectors?

i believe i am touching both pieces, ever so slightly. i tried one of
the other cables in the scheme that has a longer inner conductor - to
allow the connection of that alone, but it didn't improve the picture.
perhaps i really am only touching the gound part of the coax to the
ground part of the tv connector. that would explain why when i fully
engage the connector, the signal gets crappy. i will try some other
combinations to see if i can clarify what i am doing.


It sounds like you no longer have a good circuit up to your antenna, and by
just touching one conductor to the TV antenna connector your downlead is
acting like a "longwire antenna", which gives some signal. When it is fully
connected, the shield is grounded and now little if any signal reaches the
TV.

Richard Clark wrote:
On 20 Oct 2004 07:09:45 -0700, (mediancat) wrote:


Is the new antenna pointed in the right direction? Try turning it
through all 360° to see how that improves/degrades the situation.
This presumes you have all the right connections of course.

yes, its pointed west as the guy at the station has suggested. i did
go up and rotate it through the compass points just to be sure there
wasn't a better direction for it.

As you are using two antennas, how are you connecting them to the
same TV or VCR? As you have tried this antenna individually and
still found no happy conclusion, it would seem to be an elemental
problem.

in seattle, this antenna scheme is sold specifically to pull in a
station that is west of the city, when all the other local stations
are in town. so my main antenna points north toward downtown
seattle, and this smaller one, that i mounted as instructed (on the
same pole) points west. there is this small plastic box that is
part of this kit. it too is mounted to the pole. i guess it's a
splitter. i plug the little and big antennas into the box and a
third cable runs down to the house. the station is not terribly far
away - it used to come in fine, and they haven't degraded the
signal. i live kind of on a hill so i don't think a building or
hill is interfering with my signal path. when the coax connector is
plugged into the tv, and all the other stations come in, channel 13
is snowy. you can barely make out what is going on.

Hi OM,

By this I presume you live south of Kent in Auburn or Puyallup (I live
in Seattle too).

TV in this area is so ubiquitous that you should get channel 13 by
waving your....

It sounds like you are trying to put Channel 13 into the UHF connector
instead of the VHF connector of your TV. The box you speak of sounds
like a VHF/UHF combiner, and I don't hear its twin at the other end of
the line being used (a VHF/UHF separator). If you are not using or do
not watch UHF (don't watch Channel 22?) then you need a simple
combiner. However, I think that is distinctly unlikely that you would
not be watching FOX - or maybe it's WB, I've gotten so use to the
cable channel mix I've lost track of the over-the-air slots.

Anyway, this sounds like an UHF/VHF splitting/combining problem now.

Since most set nowadays have the U/V splitter built in, I doubt that is what
he has. Up the pole is probably a simply 2 to 1 wideband splitter. I'm
assuming his 'main' antenna is an 'all channel' type, and the secondary is
cut specifically to channel 13.

I'd go out and buy a new splitter, some coax, connectors (with rubber boots
and weatherproofing grease). Somewhere there's a dodgy connection; and if
he has all those on hand, he'll be able to fix it. Perhaps he can reuse the
old coax, if he doesn't have to cut off too much in order to 'make' the new
connections. If water has migrated down the coax, he's better off to
replace it anyhow.

I'd also pay particular attention to the connections on the antennas
themselves, as well as verify their general condition.

I'd bet anything he'll find some corrosion up there somewhere....

With a system set up as described, I'm surprised he doesn't get some
ghosting on channel 13 from the reflected signal coming off his main
antenna. If so, trapping that channel before the splitter (combiner) would
reduce the effect.

jak

jak

73's
Richard Clark, KB7QHC

"mediancat" wrote in message
om...

| in seattle, this antenna scheme is sold specifically to pull in a
| station that is west of the city, when all the other local stations
| are in town. so my main antenna points north toward downtown seattle,
| and this smaller one, that i mounted as instructed (on the same pole)
| points west. there is this small plastic box that is part of this
| kit. it too is mounted to the pole. i guess it's a splitter.

Try a dollar store splitter. It'll work in reverse as a combiner near enough
to test - and it's only a buck!

| i plug
| the little and big antennas into the box and a third cable runs down
| to the house. the station is not terribly far away - it used to come
| in fine, and they haven't degraded the signal. i live kind of on a
| hill so i don't think a building or hill is interfering with my signal
| path. when the coax connector is plugged into the tv, and all the
| other stations come in, channel 13 is snowy. you can barely make out
| what is going on.

On Wed, 20 Oct 2004 12:31:41 -0500, "jakdedert"
wrote:

With a system set up as described, I'm surprised he doesn't get some
ghosting on channel 13 from the reflected signal coming off his main
antenna. If so, trapping that channel before the splitter (combiner) would
reduce the effect.

Hi jak,

Reflected signals on a nearby antenna (like one on the same mast) is
going to be totally invisible. The scan line crosses the screen in
62µS and an RF signal will travel 10 Miles in that time. For a ghost
to be observed the original and the reflection must exhibit some
significant portion (or multiple plus offset) of that value. Let's
arbitrarily call your TV 10 inches wide and set the reflection with a
1 mile path difference. Thus the two images (original and ghost)
would be offset by one inch.

Now let's ramp that 1 mile difference down to a couple of feet (those
two adjacent antennas). You should then appreciate that 1 inch ghost
offset will shrink to sub mm (to mix units). Conventional TV
bandwidths could not resolve the difference.

73's
Richard Clark, KB7QHC