Tall Vertical No Holes Roof Mount Idea

[AF6D]

I lost the house in the divorce. Actually, I gave it to her and let her sell it. I lease a wonderful home at 6,333 feet over So. California and cannot drill holes into someone else's roof. I have devized an idea of using two sheets of 1" MDF that has been weather treated, coinder blocks and a tripod to mount a 28 foot tall Zero-Five vertical. I'd love some feedback on this idea and potential designe changes / ideas. We get plenty of snow up here (and rain), so the added 511 pounds of weight needs to be centered over two supports. The idea is to guy the antenna on a base that doesn't want to slide around. During snow season it is not uncommon to have 2-3 feet of packed snow on the roof.

http://af6d.com/roofmount.php

Comments are encouraged.

My other plan is a 50 gallon drum filled with sand, a 20 foot mast, and a Zero-Five guyed. Sand weighs about 500 pounds. Concrete about 897 pounds but an SOB to move.

Don't call me crazy -- call me a ham!

[KB4MB]

Honestly, I would go for the drum and see it you can attach with bracket near the house.  I have had roof leaks before (not due to antennas), and once you get one, it is a pain in the rear.  Plus, you are now opening the door for problems somehow being blamed on you cause you modified someone elses property.

I imagine you can use the guys as radials in that situation as well.  Easy to take down - I think you will be happier in the long run.

[AJ3O]

While a roof mount tower and antenna is a decent load, it is still within the design spec's of most modern roofs for "Dead Load Rating". Would I put that much weight on a roof? No. Even with it spaced out over various roof joists/rafters, it would far exceed that dead load rating for the roof. and then the added weight of that snow and, well, it would be pretty cold in that house just long enough for you to tell the owner what happened and why. Then your only heat would be from your car's heating system.....

Please, and seriously, do NOT put that much weight on the roof unless the owner had it fortified and built with concrete with a design load far exceeding what you intend to do.


Just my .02 


Now, an old truck rim laying flat on its side on top of a sheet of that 1" MDF, with a piece of heavy gauge pipe welded vertically into the center of the rim might work. Just mount the antenna on the mast, get the guy wires attached at predetermined heights on the mast and the antenna. Anchor two of the three guys and use the third to pull the assembly up. Then anchor the last guys on that third side. That should get you close. Might not be a permanent solution, but there are many others that have some ideas and info all over the internet.

[M6GOM]

Why not just ground mount the antenna and lay out radials?

[AF6D]

The Zero Five is a 28 foot tall groundplane antenna with 6 100" radials attached. It wants to be a least 6 feet off the ground. http://www.zerofive-antennas.com/content/groundplane-10-40-meter-high-performance-multiband-vertical-antenna Otherwise your suggestion makes perfect sense. When ground mounted it is slightly less effective than my Alpha Delta DXCC wire dipole at 60-80 feet. My friend has a ZeroFive atop an 8,000 foot mountain at a repeater site and he kicks my butt. I have a FT-2000 with current PEP firmware and a 1KW amp. He has a a Kendwood TS-430 and 100 watts and works the world. I'm at 6,300 feet also at a repeater site and cannot compete. It really tixkws me off to have better equipment and hear less (although the FT-2000 is questionable.) The solution according to ZeroFive is to get the antenna as high as possible.

Thanks for the input. I'd love more feedback on the roof mount I have designed.

[K3ANG]

I vote for the 50 gallon drum filled with sand, a 20 foot mast, and whatever you decide to put up.
Makes life easier for you and your landlord.

[AF6D]

Well, I think I've decided on THREE 50 gallon drums filled with sand. That will be about 1300 lbs. of vertical weight and a horizontal footprint or base. The winds do kick up pretty good up here. I will have a steel plate welded connecting the three drums together top and bottom. A 3" hole at the top for a mast and a 3" flange mount at the bottom to attach the mast. Up 15 feet or so to a 3" to 2" reducer and then up anther 30 feet onto which the 28 foot vertical will be afixed. I'll have to have the top of the 2" mast lathed down to 1 7/8" to accomdate the mounting of the ZeroFive. I will then have to figure out how to guy it at the mid point since it won't be on the roof of the house.

Another option would be a 20 foot triangular tower section with a bottom plate onto which steel drums could be welded. I like this approach, too. This would allow me to push it up against the 12" beams of my upper balcony and afix it with minimal disturbance to the structure. There are already bolt holes and a cap could be made to go over the 12" x 4" beam and line up with the bolt holes at the 10 foot mark. I could still do the same with the 3" mast and saddle clamps.