Some options for putting a dipole on community roof (pics included for ideas)

[KJ4WMQ]

No idea on the tree. here are the pics of the tree, and the window to tree pics...

[WB2WIK]

Without a close-up shot of a single leaf, I really don't know what kind of tree that is, either, but I can't believe it's 125 feet tall.

Based on an estimated height of 25' to the peak of the roof of the 2-story buiilding, the tree appears to be about 60 or 70 feet. That's still plenty high for what you want to do.

Most tree species don't grow to 125 feet.

Here in California, we have Redwoods and Sequoias that do. They're also 2000 years old or more. They live to be that old and that tall because they're nearly immune to everything Nature has to throw at them, including horrendous winds, and fires.

[K9DPJ]

If I were in your situation I'd consider a loop antenna close to the roof (as high as possible above it, without being too noticeable) with short supports in the roof corners to make a loop about 275' in perimeter (if it were square, this would be 68'9" on a side, but it doesn't have to be square, it can have an odd shape) and feed that at a break point in the loop.

Is this the same as a rhombic?

[WA8FOZ]

That tree is BEGGING to support some sort of wire! It coould be either the apex of a loop or the center feedpoint of an inverted-V. I think I would do the V, but the loop might be a bit more stealthy. Choice may largely depend on the way you want to feed it. Either way, you have a setting for a quite decent multiband antenna. Good luck!

[KJ4WMQ]

I'll get a pic of the leaf for ya...

I just used an app on my phone ot figure out height. it uses the accelerometer to figure out the height from the bottom of the tree and angle you gotta tilt the phone to get the next point

[KJ4WMQ]

That tree is BEGGING to support some sort of wire! It coould be either the apex of a loop or the center feedpoint of an inverted-V. I think I would do the V, but the loop might be a bit more stealthy. Choice may largely depend on the way you want to feed it. Either way, you have a setting for a quite decent multiband antenna. Good luck!

loop, like make a big loop inside the tree?

I was thinking shoot up one end of an end fed wire as high as I can get it, and then bring it down to the roof (so about 70 feet to 30 feet) it would be high end to low end that's W-E running. so i'd have little gain towards E (europe) or I can run it from the tree to my window (you can see the wire from the 2M antenna going into my window) that window faces north

it could be a good tree to have a sloped antenna.

and how about swaying of the tree? if I have the 'end' attached to my roof, and the other end to the tree, and the tree sways, I assume it's going to win the battle against my wire antenna... one thing i can do I guess is run a pvc pipe through the end fed antenna, and have it setup so that the wire is loose in the hole of the pvc. so when the tree sways around, it won't pull on a cable that's tied down. I'm gonna need something so that the cable is always tight though, otherwise it's gonna sag in the middle... not sure if some sag would affect anything

[WB2WIK]

I'll get a pic of the leaf for ya...

I just used an app on my phone ot figure out height. it uses the accelerometer to figure out the height from the bottom of the tree and angle you gotta tilt the phone to get the next point

How can an accelerometer do that?

An inclinometer might, but only if you know the exact distance from your device to the base of the target and can aim a very sharply focused beam to the top of the target. Golf trainers sometimes use these to determine how to aim a putt on a hilly green, and those use an electronic inclinometer along with a LASER as the targeting device.

[WB2WIK]

and how about swaying of the tree? if I have the 'end' attached to my roof, and the other end to the tree, and the tree sways, I assume it's going to win the battle against my wire antenna...

Usually you just leave enough slack in the rope and antenna to prevent damage from the tree swaying. For very long and heavy wire antennas, it's common to use a big spring (like a garage door type) at the lower end where it's fixed, or to use a bucket of sand or a cinder block or something as a weight on the end of that rope instead of tying it down. These are simple problems that have been long solved.

[KJ4WMQ]

I like the spring idea...

[KJ4WMQ]

How can an accelerometer do that?An inclinometer might, but only if you know the exact distance from your device to the base of the target and can aim a very sharply focused beam to the top of the target. Golf trainers sometimes use these to determine how to aim a putt on a hilly green, and those use an electronic inclinometer along with a LASER as the targeting device.

Here's the app https://market.android.com/details?i...measure&hl=enI. Gonna draw some pictures of what kind of wire positions I have in mind... I'm thinking slope from the tree to the roof.Also, my slim Jim antenna... Amy other ideas on how I could improve that antenna, or what I can replace itnwith to better my VHF/UHF? I don't want that antenna taller than 6 feet