On Sun, 22 May 2011 17:55:16 -0500, John KD5YI
wrote:

* Try moving your existing antenna. Even a small movement may cure the
problem as you may have cancelling reflections at times. There is almost
always a "sweet spot" somewhere in the vicinity.

I beg to differ. I have about 30 years experience in dealing with
propogation through a dense redwood forest (Ben Lomond CA). The trees
in my area are about 120ft high. While moving the antenna around may
temporarily improve the signal quality by reducing frequency selective
fading, multipath, reflections, and just plain bad luck, they do not
tend to remain improved. Trees grow and move around. What works well
now, will probably not work well tomorrow.

I gave up on fixed antenna mounts for my rooftop verticals. (Well, I
have one mounted on a tripod, but that was before I realized what was
happening). Most of my verticals are mounted on 2x12 planks, held
down to the roof with sand bags, concrete blocks, and buckets full of
water. Every few months, I move the antennas around to see if I can
improve the signals to specific repeaters.

* Try tilting your antenna to 45 degrees and see if that helps. It might
improve reception due to the random polarization of the incoming signal
caused by the trees.

I beg to differ again. Tree trunks are mostly water and do an
impressive job of simulating a slot type polarization filter at 2m and
440Mhz frequencies. Leaves and branches will pass RF fairly well, but
not tree trunks. I've played with both polarizations, circular
polarization:
http://802.11junk.com/jeffl/circular-polarization/
and some diversity reception. Empirically, signals are about 6dB
stronger going through the trees vertically polarized, than
horizontal. The effect continues up to at least 2.4GHz. Above that,
at 5.7GHz, the signals seem to be going through the holes between the
leaves.

I must admit that I haven't actually tried 45 degrees on 2m or 440Mhz,
but I don't think it will help much. Still, it's an easy thing to
try.

Note: do this on a day when the signal is either weak or non-existent.
You can always apologize for kerchunking. Or, use your S-meter if you
have one.

Do it on a windy day, when the trees are moving around, so you can see
how much it will change.

Cheers & Good Luck,
John
KD5YI

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 5/22/2011 8:26 PM, Jeff Liebermann wrote:
On Sun, 22 May 2011 17:55:16 -0500, John
wrote:

* Try moving your existing antenna. Even a small movement may cure the
problem as you may have cancelling reflections at times. There is almost
always a "sweet spot" somewhere in the vicinity.

I beg to differ. I have about 30 years experience in dealing with
propogation through a dense redwood forest (Ben Lomond CA). The trees
in my area are about 120ft high. While moving the antenna around may
temporarily improve the signal quality by reducing frequency selective
fading, multipath, reflections, and just plain bad luck, they do not
tend to remain improved. Trees grow and move around. What works well
now, will probably not work well tomorrow.

You may be right, Jeff. But he may not have 120ft redwoods around and,
after all, this is a temporary fix until his yagi comes in.

I gave up on fixed antenna mounts for my rooftop verticals. (Well, I
have one mounted on a tripod, but that was before I realized what was
happening). Most of my verticals are mounted on 2x12 planks, held
down to the roof with sand bags, concrete blocks, and buckets full of
water. Every few months, I move the antennas around to see if I can
improve the signals to specific repeaters.

Good for you! Pat yourself on the back.

* Try tilting your antenna to 45 degrees and see if that helps. It might
improve reception due to the random polarization of the incoming signal
caused by the trees.

I beg to differ again. Tree trunks are mostly water and do an
impressive job of simulating a slot type polarization filter at 2m and
440Mhz frequencies. Leaves and branches will pass RF fairly well, but
not tree trunks. I've played with both polarizations, circular
polarization:
http://802.11junk.com/jeffl/circular-polarization/
and some diversity reception. Empirically, signals are about 6dB
stronger going through the trees vertically polarized, than
horizontal. The effect continues up to at least 2.4GHz. Above that,
at 5.7GHz, the signals seem to be going through the holes between the
leaves.

I must admit that I haven't actually tried 45 degrees on 2m or 440Mhz,
but I don't think it will help much. Still, it's an easy thing to
try.

You spent more words debunking the suggestion than admitting that you
don't really know whether it could help or not. Good move. And, by the
way, I have experience to the contrary at both 144 and 444 MHz. It all
depends on the location of the source and the receiver. At 2 meters,
some rotation of the antenna can sometimes be helpful. Note that we are
not concerned with GHz.

John

On Sun, 22 May 2011 20:56:52 -0500, John KD5YI
wrote:

You may be right, Jeff. But he may not have 120ft redwoods around and,
after all, this is a temporary fix until his yagi comes in.

30 years of trying to maintain a stable signal to several distant
repeaters is sufficient to convince me. Trees move and grow, causing
signals to change.

Also, temporary is a rather useless term. In my experience, if it
works, it's permanent.

Good for you! Pat yourself on the back.

Thank you for the traditional contentious remark.

You spent more words debunking the suggestion than admitting that you
don't really know whether it could help or not.

True. I spent more words explaining why I suspect it will not work,
what I expect will happen, and a bit of substantiation. I consider
this a substantial improvement over the traditional one-line
pontification.

Good move. And, by the
way, I have experience to the contrary at both 144 and 444 MHz. It all
depends on the location of the source and the receiver. At 2 meters,
some rotation of the antenna can sometimes be helpful.

Perhaps it would be helpful if you read what I had written. I said
that rotating the antenna might help temporarily, but that movements
of the trees, tree growth, swaying branches in the wind, and possibly
sources of reflections, will soon negate any temporary benefits. If
the yagi is going to arrive shortly, then tilting the antenna is
probably a useful exercise.

Note that we are not concerned with GHz.

Topic drift follows:
Since you mentioned GHz, one of the other problems with living in the
deep dark forest is that DBS satellite dish reception is a problem. I
hacked an 8ft diameter hole in the tree canopy by lopping off some
branches at about the 80ft level, through which I point my DirecTV
dish. Every year, the trees grow a little, requiring that I move the
dish around my roof. During the twice annual solar satellite outage:
http://en.wikipedia.org/wiki/Sun_outage
Twice a year, I photograph the sunlight shining through the hole and
onto the dish and roof. If there are shadows of branches on the dish,
I move it to a better location.
http://www.11junk.com/jeffl/pics/DBS/
Note the shadow at 12 o'clock on the dish.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 5/22/2011 11:26 PM, Jeff Liebermann wrote:
On Sun, 22 May 2011 20:56:52 -0500, John
wrote:

You may be right, Jeff. But he may not have 120ft redwoods around and,
after all, this is a temporary fix until his yagi comes in.

30 years of trying to maintain a stable signal to several distant
repeaters is sufficient to convince me. Trees move and grow, causing
signals to change.

Also, temporary is a rather useless term. In my experience, if it
works, it's permanent.

The OP already said he will be putting up a yagi. Anthing he does
between now and then is temporary.

Good for you! Pat yourself on the back.

Thank you for the traditional contentious remark.

You earned it.

You spent more words debunking the suggestion than admitting that you
don't really know whether it could help or not.

True. I spent more words explaining why I suspect it will not work,
what I expect will happen, and a bit of substantiation. I consider
this a substantial improvement over the traditional one-line
pontification.

I find it more useful to encourage experimentation rather than the opposite.

Good move. And, by the
way, I have experience to the contrary at both 144 and 444 MHz. It all
depends on the location of the source and the receiver. At 2 meters,
some rotation of the antenna can sometimes be helpful.

Perhaps it would be helpful if you read what I had written. I said
that rotating the antenna might help temporarily, but that movements
of the trees, tree growth, swaying branches in the wind, and possibly
sources of reflections, will soon negate any temporary benefits. If
the yagi is going to arrive shortly, then tilting the antenna is
probably a useful exercise.

I did read what you had written. So?

Note that we are not concerned with GHz.

Topic drift follows:
Since you mentioned GHz,

*You* are the one who brought it up:

"The effect continues up to at least 2.4GHz. Above that,
at 5.7GHz, the signals seem to be going through the holes between the
leaves."

Perhaps you should read what you wrote.

John

On Sun, 22 May 2011 20:56:52 -0500, John KD5YI
wrote:

You may be right, Jeff. But he may not have 120ft redwoods around and,
after all, this is a temporary fix until his yagi comes in.

Ummm... I don't think the yagi is on order.
http://www.k7jep.org/node/107

#Begin speculation();

His area has a variety of repeaters available:
http://www.k7jep.org/node/107
I would guess(tm) N7JCT 145.230 on Schweitzer Mtn. Idaho.
http://www.repeaterbook.com/beta/repeaters/details.php?ID=64&state_id=16
Plugging the coordinates 48.367500 -116.628326 into Google Earth gives
me a view of the area. It seems to be in the middle of a ski resort,
that has been cleared of most trees and is full of trails. Plenty of
trees both up and down the slope, but not around the probable location
of the repeater. I can't identify the trees from the photo, but my
guess(tm) is Lodgepole Pine at about 60ft. The location is not at the
top of the hill and also has hills shading the view for about 270
degrees. I don't think this is going to be a foliage penetration
issue.

KML file for Google Earth:
http://802.11junk.com/jeffl/kml/N7JCT possible location.kml
JPG for those without Google Earth:
http://802.11junk.com/jeffl/kml/N7JCT possible location.jpg

Blundering forward, N6SXR is shown as getting his snail mail in
Sandpoint ID a distance of about 7 miles. However, there's quite a
bit of dirt in the way, which will be a problem.
http://802.11junk.com/jeffl/kml/N6SXR to N6JCT.jpg

At 7 miles, it should be possible on VHF, even with 450ft of dirt in
the way. My guess(tm) is that there's something wrong with the home
made J-pole, coax, radio, or all the aformentioned.

Again, this is a guess(tm) of both the repeater and it's location and
just might be totally wrong.

#End speculation();


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 5/23/2011 10:46 AM, Jeff Liebermann wrote:
On Sun, 22 May 2011 20:56:52 -0500, John
wrote:

You may be right, Jeff. But he may not have 120ft redwoods around and,
after all, this is a temporary fix until his yagi comes in.

Ummm... I don't think the yagi is on order.


Now you are just being argumentative. I never said it was on order. The
OP said he was planning to put one up. Therefore, it will most likely
come in some day.

I'll bet you are still waiting for your boat to come in.

On Mon, 23 May 2011 11:46:58 -0500, John KD5YI
wrote:

On 5/23/2011 10:46 AM, Jeff Liebermann wrote:
On Sun, 22 May 2011 20:56:52 -0500, John
wrote:

You may be right, Jeff. But he may not have 120ft redwoods around and,
after all, this is a temporary fix until his yagi comes in.

Ummm... I don't think the yagi is on order.

Now you are just being argumentative.

Not really. Methinks that you're being overly defensive. My litmus
test is "duz it answer the OP's question"? If not, you're wasting
your bytes. By asking for help with the design and contruction of a
yagi, it appears that the author is planning to build his own yagi. I
haven't seen any mention of a structure, pole, or tower, so that will
also need to be constructed. Perhaps also a rotator. Methinks
temporary might be a long time.

I never said it was on order. The
OP said he was planning to put one up. Therefore, it will most likely
come in some day.

At this point, I think were suppose to debate the definition of
temporary. I think I'll pass.

I'll bet you are still waiting for your boat to come in.

Nope, no waiting. I let the computah do that for me.
http://www.marinetraffic.com/ais/
The station I'm slightly involved with is at:
http://www.marinetraffic.com/ais/stationdetails.aspx?station_id=112
Watching the VHF propagation effects are fascinating.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann said the following on 5/23/2011 8:46 AM:
On Sun, 22 May 2011 20:56:52 -0500, John
wrote:

You may be right, Jeff. But he may not have 120ft redwoods around and,
after all, this is a temporary fix until his yagi comes in.

Ummm... I don't think the yagi is on order.
http://www.k7jep.org/node/107

This is the repeater I am trying to access, 146.780, K7JEP. I have been
playing with Google Earth and getting coordinates so I can go over to my
neighbors property and stand on the ridge between our properties and see
if I can see the repeater and my house. Hopefully that will help me
locate the suspect trees.


#Begin speculation();

His area has a variety of repeaters available:
http://www.k7jep.org/node/107
I would guess(tm) N7JCT 145.230 on Schweitzer Mtn. Idaho.

This repeater is 59 on signal. I have direct line of site with no
obstructions.

http://www.repeaterbook.com/beta/repeaters/details.php?ID=64&state_id=16
Plugging the coordinates 48.367500 -116.628326 into Google Earth gives
me a view of the area. It seems to be in the middle of a ski resort,
that has been cleared of most trees and is full of trails. Plenty of
trees both up and down the slope, but not around the probable location
of the repeater. I can't identify the trees from the photo, but my
guess(tm) is Lodgepole Pine at about 60ft. The location is not at the
top of the hill and also has hills shading the view for about 270
degrees. I don't think this is going to be a foliage penetration
issue.

KML file for Google Earth:
http://802.11junk.com/jeffl/kml/N7JCT possible location.kml
JPG for those without Google Earth:
http://802.11junk.com/jeffl/kml/N7JCT possible location.jpg

Blundering forward, N6SXR is shown as getting his snail mail in
Sandpoint ID a distance of about 7 miles. However, there's quite a
bit of dirt in the way, which will be a problem.
http://802.11junk.com/jeffl/kml/N6SXR to N6JCT.jpg

Addresses here are not all they seem. My physical address is 14 miles
north even though the postal idiots label it in Sandpoint. Approx
location... lat 48.494070 lon -116.447788. You'll see my crazy driveway
and the house. The J-pole sits about 30' above the house. Plenty of
trees in sight.

At 7 miles, it should be possible on VHF, even with 450ft of dirt in
the way. My guess(tm) is that there's something wrong with the home
made J-pole, coax, radio, or all the aformentioned.

Again, this is a guess(tm) of both the repeater and it's location and
just might be totally wrong.

#End speculation();




--
'Captain' Kirk DeHaan
N6SXR

"Beam me up Scotty, there's no intelligent life here"

On Mon, 23 May 2011 15:53:28 -0700, 'Captain' Kirk DeHaan
wrote:

You'll see my crazy driveway
and the house. The J-pole sits about 30' above the house. Plenty of
trees in sight.

That's quite a drive. Thanks for the numbers. I've ignored the
antenna heights as they don't seem to make much difference. 31 km (19
mile) path length. The K7JEP repeater seems to be on a wide flat part
of a hilltop. Pointing downward, it may not clear the edge of the
flat part if the antenna isn't high enough. Difficult to tell without
photos or numbers. Not much you can do at your end to fix that. Any
chance you have a photo of the K7JEP repeater antenna location?

Otherwise, the path is line-o-sight, and should be quite usable with
your American Legion J-Pole. Of course, a yagi would be better, but I
think tinkering with your J-pole, coax, connectors, and radio may be a
better solution (assuming the repeater is working properly).

KML file:
http://802.11junk.com/jeffl/kml/N6SXR-to-K7JEP.kml

JPG image:
http://802.11junk.com/jeffl/kml/N6SXR-to-K7JEP.jpg

Hint: In Google Earth, enable 3D. When you have the KML file
displayed, stomp on the MIDDLE mouse button to tilt the image.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann said the following on 5/24/2011 8:47 AM:
On Mon, 23 May 2011 15:53:28 -0700, 'Captain' Kirk DeHaan
wrote:

You'll see my crazy driveway
and the house. The J-pole sits about 30' above the house. Plenty of
trees in sight.

That's quite a drive. Thanks for the numbers. I've ignored the
antenna heights as they don't seem to make much difference. 31 km (19
mile) path length. The K7JEP repeater seems to be on a wide flat part
of a hilltop. Pointing downward, it may not clear the edge of the
flat part if the antenna isn't high enough. Difficult to tell without
photos or numbers. Not much you can do at your end to fix that. Any
chance you have a photo of the K7JEP repeater antenna location?

Otherwise, the path is line-o-sight, and should be quite usable with
your American Legion J-Pole. Of course, a yagi would be better, but I
think tinkering with your J-pole, coax, connectors, and radio may be a
better solution (assuming the repeater is working properly).

I have heard from a club member that the repeater is weak and it has
been overrun by one on the coast! He is much farther away than me and
in a much less desirable location, signal wise.

I have been out of HAM radio for about 15 years so am having to relearn
quite a lot. Had a brain injury, doh!, so lot's of what I knew went bye
bye. Lot's of holes in the memory. I will find out about the repeater
during the next club meeting. Specs and all.


KML file:
http://802.11junk.com/jeffl/kml/N6SXR-to-K7JEP.kml

JPG image:
http://802.11junk.com/jeffl/kml/N6SXR-to-K7JEP.jpg

Hint: In Google Earth, enable 3D. When you have the KML file
displayed, stomp on the MIDDLE mouse button to tilt the image.


--
'Captain' Kirk DeHaan
N6SXR

"Beam me up Scotty, there's no intelligent life here"