Two Antennas for HDTV OTA?

Starting with your zip code and entering a height of 150 feet (to get
a full list of the local digital stations w/o very local ground terrain
for the zip), I get the following digital stations from antennaweb.org:

* yellow - uhf KONG-DT 16.1 IND EVERETT WA 336° 16.3 31
* yellow - uhf KTBW-DT 14.1 TBN TACOMA WA 277° 24.7 14
* yellow - uhf KING-DT 5.1 NBC SEATTLE WA 336° 16.3 48
* yellow - uhf KIRO-DT 7.1 CBS SEATTLE WA 335° 16.5 39
* yellow - uhf KOMO-DT 4.1 ABC SEATTLE WA 335° 16.3 38
* yellow - uhf KBTC-DT 28.1 PBS TACOMA WA 211° 12.4 27
* yellow - uhf KCPQ-DT 13.1 FOX TACOMA WA 277° 25.3 18
* yellow - uhf KMYQ-DT 22.1 MNT SEATTLE WA 343° 15.2 25
* yellow - uhf KWOG-DT 51.1 IND BELLEVUE WA 47° 17.8 50
* yellow - uhf KWDK-DT 42 DAY TACOMA WA TBD 47° 17.8 42
* yellow - uhf KWPX-DT 33.1 i BELLEVUE WA 47° 17.8 32
* yellow - uhf KCTS-DT 9.1 PBS SEATTLE WA 343° 15.2 41
* blue - uhf KSTW-DT 11.1 CW TACOMA WA 343° 15.1 36
* violet - uhf KHCV-DT 44.1 SAH SEATTLE WA 47° 17.8 44

You have 3 main groups of stations in azimuth: ~ 47 degrees at 18
miles, 277 degs at 25 miles, and ~ 340 degrees at 16 miles. All are
currently digitally broadcasting on UHF (the last number in the row).
Challenging situation but the good news is that most of the stations are
close. Inside of 25 miles is not far for a rooftop mount. You would
probably get a lot of these stations with an indoor antenna such as the
Silver Sensor.

You may to go with 2 antennas, but I would go with a single good
multidirectional antenna first. As I posted earlier, I get stations
scattered in all directions with a Channel Master 4221 out to 45 miles.
My advice to order a CM 4221 and put just that antenna up to see what
you can get. Try aiming it at the more distant stations in Tacoma first.
Then be prepared to climb up there and tweak the aim a few times (or
have someone stay up on the roof) while you do a lot of channel scans.
If some stations are marginal, then buy a Channel Master or Winegard
pre-amp. The Channel Master 7777 pre-amp is a very good one, but it may
be more of a boost than you need.

I brought my CM 4221 from http://www.solidsignal.com/antennas/ and was
happy with their service. http://www.warrenelectronics.com/ are also
respected on-line dealers. Figure around $25 on-line for the CM 4221
plus shipping. For pre-amps, there is a CM and Winegard pre-amp
comparison table at
http://www.solidsignal.com/antennas/preamplifiers.asp. But hold off on a
pre-amp until you see what you can get with a CM 4221.

I can't guarantee that a single CM 4221 will get all your locals. But
putting up and adjusting the line delay from 2 antennas is enough of a
headache, that you should try the CM 4221 by itself first.

Now to muddy the waters, there is the issue of what will happen on
Feb. 17, 2009 when the analog shutdown is scheduled to occur. The
information on what broadcast channels stations have selected to switch
to is available at the DTV section at fcc.gov. Three of your upper VHF
locals: KCTS PBS 9, KSTW CW 11, KCPQ Fox 13 will be switching to their
current analog channels. The low VHF stations and KIRO CBS 7 have opted
to stay at UHF as few stations have selected to return to low VHF. The
CM 4221 has some pickup for upper VHF, but it may not get all 3 of
those stations. if you run into problems then, you can add a upper VHF
antenna which does not have to be all that big. I can expand on this if
you really want me to, but this does muddy the issue. I personally think
the CM 4221 will get the upper VHF stations then because they are not
all that far away.

Whew, that was a long post. Hope this helps!
Alan F


Richard Minami wrote:
Thanks for all the help! I'm in 98198. Oh, and I originally said ~60
degrees apart, but it should be ~120 degrees. (high school geometry was a
long time ago...)

I'm hoping the problem is my old antenna, with one of the longest conductors
drooping. I have a new one in the garage (a little bit larger than the one
I have now, boom length like 5" longer), but I haven't put it up yet. Snow
around Seattle, probably not a safe time to be on the roof! I'm hoping the
new antenna and a new coax cable will capture more HDTV OTA.

Our current coax cable isn't shielded very well (I think that's how you'd
say it). The copper core is good, then the white plastic cover is okay,
then the foil like material is intact, but the next layer has like 4 wires,
then the black rubbery outer cover. The cable I got from my Dad has more of
a braided layer (instead of the 4-5 wires on our current cable). Is that
shielding or more conductivity? I feel like it would be better
conductivity. The tip is a screw on, instead of a crimp, and when I wiggle
the connector, sometimes I can get NBC in HD, sometimes not. This is my
weekend project, to put up the new antenna and pull the new coax (about
40-50 feet).

NBC, ABC, CBS and a PBS station all broadcast from Seattle. But Fox, WB,
and another PBS station broadcast from Tacoma. I'm hoping to get them all,
since analog broadcasts are supposedly going away in a few years.

Richard

G-squared:

You said that 'ghosts' are not a problem but they are.
I didn't mean to imply it wasn't a problem.

I understand your point which is why I asked if an omni-directional
antenna would work. I guess a multi-directional would have been a better
suggestion.

--
Mac Cool

Richard Minami wrote:
Thanks for all the help! I'm in 98198. Oh, and I originally said ~60
degrees apart, but it should be ~120 degrees. (high school geometry was a
long time ago...)

I'm hoping the problem is my old antenna, with one of the longest conductors
drooping. I have a new one in the garage (a little bit larger than the one
I have now, boom length like 5" longer), but I haven't put it up yet. Snow
around Seattle, probably not a safe time to be on the roof! I'm hoping the
new antenna and a new coax cable will capture more HDTV OTA.

Our current coax cable isn't shielded very well (I think that's how you'd
say it). The copper core is good, then the white plastic cover is okay,
then the foil like material is intact, but the next layer has like 4 wires,
then the black rubbery outer cover. The cable I got from my Dad has more of
a braided layer (instead of the 4-5 wires on our current cable). Is that
shielding or more conductivity? I feel like it would be better
conductivity. The tip is a screw on, instead of a crimp, and when I wiggle
the connector, sometimes I can get NBC in HD, sometimes not. This is my
weekend project, to put up the new antenna and pull the new coax (about
40-50 feet).

NBC, ABC, CBS and a PBS station all broadcast from Seattle. But Fox, WB,
and another PBS station broadcast from Tacoma. I'm hoping to get them all,
since analog broadcasts are supposedly going away in a few years.


Actually the WB station is now MyNetwork and it broadcasts from Seattle
(Capitol Hill, same location as the PBS and CW stations). The Fox
station is licensed to Tacoma but the transmitter is near Bremerton
(Gold Mountain).

It is best to use compression connectors rather than crimp (or *ugh*
twist-on). I got a Datashark compression tool at Home Depot for $15.
The foil supplies the needed conductivity for the outer conductor of the
cable. Use RG-6, rather than RG-59. It has less loss.

Mac Cool wrote:
G-squared:

You said that 'ghosts' are not a problem but they are.
I didn't mean to imply it wasn't a problem.

I understand your point which is why I asked if an omni-directional
antenna would work. I guess a multi-directional would have been a
better
suggestion.

--
Mac Cool

OK, the issues with an omni antenna are

1: not much in the way of ghost rejection and
2: not much 'gain' like you would get with a directional antenna.

However, certainly try one because it may be adequate in which case
you're done and enjoy. One of the things I've noticed now that I'm
CERTAIN the signals are all good is the receiver 'lock-up' time is
quite fast. The Samsung STB acquires the signal in less than a second.
Same is true for the ATI HDTV Wonders in the computers. Before I got it
sorted some channels took a couple of seconds to lock in and the signal
indicators would bounce around.

GG

Okay, so the new antenna is up, the new cable has been pulled and I just
fired up our set. We still don't get ABC, CBS and PBS (Seattle) in digital.
We do get KSTW in digital now, that's an improvement. But we also still
don't get PAX, ION and QUBO (my son is excited for that, I think it goes
live some time in 2007). These last few I've been able to receive in
digital in the past with the old equipment, but it was very intermittent.
The whole reason for this exercise was to get NBC stable in digital, which
has yet to be proven. It seems like it would always flake out during Jay
Leno's monologue. So we'll see in the next few days.
Thanks for everyone's help! I've learned a lot. I think the
omnidirectional antenna would not provide enough gain to recieve some of the
more distant stations. Maybe some day I'll need to climb up into the big
maple tree that blocks signal from Seattle and mount the antenna up there.
Richard


"Richard Minami" wrote in message
...
Hi! Does anyone know if I can run two roof top antennas concurrently? I
live between two metropolitan areas that are about 60 degrees apart. Can
I point one antenna to the north, and then use a splitter to add another
antenna pointing south west? Then I'd run the one cable into my HD
receiver. I've heard that analog signals may ghost because the two
antennas are receiving the signal at different angles. But would a
digital broadcast do the same thing? Thanks!
--
Richard

Richard, what antenna did you put up and where it is aimed? The Seattle
stations are only 16 miles away from your zip code, so you must have
severe local obstructions (takes more than a tree) if those stations
don't come in or not have the right antenna for the situation.

Alan F


Richard Minami wrote:

Okay, so the new antenna is up, the new cable has been pulled and I just
fired up our set. We still don't get ABC, CBS and PBS (Seattle) in digital.
We do get KSTW in digital now, that's an improvement. But we also still
don't get PAX, ION and QUBO (my son is excited for that, I think it goes
live some time in 2007). These last few I've been able to receive in
digital in the past with the old equipment, but it was very intermittent.
The whole reason for this exercise was to get NBC stable in digital, which
has yet to be proven. It seems like it would always flake out during Jay
Leno's monologue. So we'll see in the next few days.
Thanks for everyone's help! I've learned a lot. I think the
omnidirectional antenna would not provide enough gain to recieve some of the
more distant stations. Maybe some day I'll need to climb up into the big
maple tree that blocks signal from Seattle and mount the antenna up there.
Richard


"Richard Minami" wrote in message
...

Hi! Does anyone know if I can run two roof top antennas concurrently? I
live between two metropolitan areas that are about 60 degrees apart. Can
I point one antenna to the north, and then use a splitter to add another
antenna pointing south west? Then I'd run the one cable into my HD
receiver. I've heard that analog signals may ghost because the two
antennas are receiving the signal at different angles. But would a
digital broadcast do the same thing? Thanks!
--
Richard

Alan F wrote:
Richard, what antenna did you put up and where it is aimed? The Seattle
stations are only 16 miles away from your zip code, so you must have
severe local obstructions (takes more than a tree) if those stations
don't come in or not have the right antenna for the situation.


Or he has too much antenna or amplification which could be overloading
the input on his receiver.

Matthew

--
Thermodynamics and/or Golf for dummies: There is a game
You can't win
You can't break even
You can't get out of the game

We're actually at the southern border of 98198, so it's more than 16 miles.
The antenna is from Radio Shack, 80".
http://www.radioshack.com/product/in...entPage=search
I don't have an exact direction. My son's toy compass probably isn't good
enough! There's actually a whole block of trees to our north. I'm starting
to think I need more height.
Richard


"Alan F" wrote in message
news:[email protected]
Richard, what antenna did you put up and where it is aimed? The Seattle
stations are only 16 miles away from your zip code, so you must have
severe local obstructions (takes more than a tree) if those stations don't
come in or not have the right antenna for the situation.

Alan F


Richard Minami wrote:

Okay, so the new antenna is up, the new cable has been pulled and I just
fired up our set. We still don't get ABC, CBS and PBS (Seattle) in
digital. We do get KSTW in digital now, that's an improvement. But we
also still don't get PAX, ION and QUBO (my son is excited for that, I
think it goes live some time in 2007). These last few I've been able to
receive in digital in the past with the old equipment, but it was very
intermittent.
The whole reason for this exercise was to get NBC stable in digital,
which has yet to be proven. It seems like it would always flake out
during Jay Leno's monologue. So we'll see in the next few days.
Thanks for everyone's help! I've learned a lot. I think the
omnidirectional antenna would not provide enough gain to recieve some of
the more distant stations. Maybe some day I'll need to climb up into the
big maple tree that blocks signal from Seattle and mount the antenna up
there.
Richard


"Richard Minami" wrote in message
...

Hi! Does anyone know if I can run two roof top antennas concurrently? I
live between two metropolitan areas that are about 60 degrees apart. Can
I point one antenna to the north, and then use a splitter to add another
antenna pointing south west? Then I'd run the one cable into my HD
receiver. I've heard that analog signals may ghost because the two
antennas are receiving the signal at different angles. But would a
digital broadcast do the same thing? Thanks!
--
Richard

On Sat, 02 Dec 2006 17:10:22 -0800, Richard Minami wrote:

Okay, so the new antenna is up, the new cable has been pulled and I just
fired up our set. We still don't get ABC, CBS and PBS (Seattle) in digital.
We do get KSTW in digital now, that's an improvement. But we also still
don't get PAX, ION and QUBO (my son is excited for that, I think it goes
live some time in 2007). These last few I've been able to receive in
digital in the past with the old equipment, but it was very intermittent.
The whole reason for this exercise was to get NBC stable in digital, which
has yet to be proven. It seems like it would always flake out during Jay
Leno's monologue. So we'll see in the next few days.
Thanks for everyone's help! I've learned a lot. I think the
omnidirectional antenna would not provide enough gain to recieve some of the
more distant stations. Maybe some day I'll need to climb up into the big
maple tree that blocks signal from Seattle and mount the antenna up there.

You said sometihng about the new antenna having a longer boom. Boom length
generally refers to VHF or uhf/vhf combo antennas. All the digital
stations in your area are UHF so if you put up a long vhf antenna you
still aren't likely to get anything. As close as you are to the towers you
shouldn't have any problems unless the signals are blocked by something.

--
Want the ultimate in free OTA SD/HDTV Recorder? http://mythtv.org
http://mysettopbox.tv/knoppmyth.html Usenet alt.video.ptv.mythtv
My server http://wesnewell.no-ip.com/cpu.php
HD Tivo S3 compared http://wesnewell.no-ip.com/mythtivo.htm

Now that it's been a few hours, my DVR/HD receiver gets all the channels!
Plus, there are a bunch of weird ones (The Asian Channel, and some gothic
channel). I get ABC, but if I use features on the DVR (like changing
settings), the signal flakes out a little (cutting audio and making the
video all blocky). But so far, I'm getting a steady picture when viewing
all our local channels! Woo hoo! Free HDTV! (well not including the time
and few new pieces of hardware).
Richard

"Richard Minami" wrote in message
...
We're actually at the southern border of 98198, so it's more than 16
miles. The antenna is from Radio Shack, 80".
http://www.radioshack.com/product/in...entPage=search
I don't have an exact direction. My son's toy compass probably isn't good
enough! There's actually a whole block of trees to our north. I'm
starting to think I need more height.
Richard


"Alan F" wrote in message
news:[email protected]
Richard, what antenna did you put up and where it is aimed? The Seattle
stations are only 16 miles away from your zip code, so you must have
severe local obstructions (takes more than a tree) if those stations
don't come in or not have the right antenna for the situation.

Alan F


Richard Minami wrote:

Okay, so the new antenna is up, the new cable has been pulled and I just
fired up our set. We still don't get ABC, CBS and PBS (Seattle) in
digital. We do get KSTW in digital now, that's an improvement. But we
also still don't get PAX, ION and QUBO (my son is excited for that, I
think it goes live some time in 2007). These last few I've been able to
receive in digital in the past with the old equipment, but it was very
intermittent.
The whole reason for this exercise was to get NBC stable in digital,
which has yet to be proven. It seems like it would always flake out
during Jay Leno's monologue. So we'll see in the next few days.
Thanks for everyone's help! I've learned a lot. I think the
omnidirectional antenna would not provide enough gain to recieve some of
the more distant stations. Maybe some day I'll need to climb up into
the big maple tree that blocks signal from Seattle and mount the antenna
up there.
Richard


"Richard Minami" wrote in message
...

Hi! Does anyone know if I can run two roof top antennas concurrently?
I live between two metropolitan areas that are about 60 degrees apart.
Can I point one antenna to the north, and then use a splitter to add
another antenna pointing south west? Then I'd run the one cable into my
HD receiver. I've heard that analog signals may ghost because the two
antennas are receiving the signal at different angles. But would a
digital broadcast do the same thing? Thanks!
--
Richard