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#1
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I would like some opinions from you experiencd folks as to an idea I have
for putting up an antenna mast. My fathers own an electrical supply warehouse so I have access to steel conduit at cost. Many years ago we used 4" conduit and elbows to build a basketball backboard pole in my folks' back yard, and the thing has stood the test of time, weather, and a generation of kids hanging from it. I have a similar idea for an antenna mount. I would like to dig a hole on the side of my house, approximetely 24" deep and 12" square. I'd like to take 12 2" conduit couples and weld them into a sheath, and then put this sheath in the hole, filling it (the hole) with cement. So I'd have a big cement block in the ground with a hollow tube in the middle. I would then take three 10' lengths of 2" conduit and weld them together using couples, and place the resulting pole into the hollow sheath in the cement. I would then use a pipe fastener strap to fasten the pole to the awning of the house, approximately 9' up from the ground. I'd pound a couple of copper lightning rods into the ground several meters away, and ground the pole to these rods with large-guage copper wire. So I'd have a grounded 28' pole above ground, anchored in a 24" deep steel sheath in the ground, and anchored at 9' to the side of the house with steel and bolts. So I'd have 21' of 2" steel conduit sitting in the air unsupported. I would then build some antenna mounts out of 1" conduit (something that would look like those little plastic tables that the use to keep the cardboard off of pizzas in their delivery boxes). I would of course then affix antennas to these mounts. Does this idea have any merit? Is 2" steel conduit rigid enough to support weight at 28' above ground? Should I go to 3" pipe instead? The more I sit here and think about it, the more I think 2" just won't be thick enough to stay rigid in high wind. I live in southeastern Arizona, and the winds here to get a little high. But my major concern would be lightning. Also, at some point we will be moving, and I'd like to just be able to take the pole, remove it from its sheath, and simply have to dig and pour at the new house. Thanks for any comments or suggestions. |
#2
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Ummm, The best thing I used was a 21' top rail for chainlink fencing.
No welding the sections together and you get 2. They fit together like standard antenna mast. this way with 2 feet in ground, you will have 40' over mast. Get some good guy wire and guy down 8' from the tip of the mast and then mount your pizza box above the guy wire coupling. this way one of the antennas can still go at the tip of the mast. It just seems easier and simpler than messing around with 3" conduit and welding with couplings and all that, especially if you are getting a new house soon. but I still like and understand the idea of the pizza box thing. On Sat, 9 Aug 2003 14:26:05 -0700, "Jason Wagner" wrote: I would like some opinions from you experiencd folks as to an idea I have for putting up an antenna mast. My fathers own an electrical supply warehouse so I have access to steel conduit at cost. Many years ago we used 4" conduit and elbows to build a basketball backboard pole in my folks' back yard, and the thing has stood the test of time, weather, and a generation of kids hanging from it. I have a similar idea for an antenna mount. I would like to dig a hole on the side of my house, approximetely 24" deep and 12" square. I'd like to take 12 2" conduit couples and weld them into a sheath, and then put this sheath in the hole, filling it (the hole) with cement. So I'd have a big cement block in the ground with a hollow tube in the middle. I would then take three 10' lengths of 2" conduit and weld them together using couples, and place the resulting pole into the hollow sheath in the cement. I would then use a pipe fastener strap to fasten the pole to the awning of the house, approximately 9' up from the ground. I'd pound a couple of copper lightning rods into the ground several meters away, and ground the pole to these rods with large-guage copper wire. So I'd have a grounded 28' pole above ground, anchored in a 24" deep steel sheath in the ground, and anchored at 9' to the side of the house with steel and bolts. So I'd have 21' of 2" steel conduit sitting in the air unsupported. I would then build some antenna mounts out of 1" conduit (something that would look like those little plastic tables that the use to keep the cardboard off of pizzas in their delivery boxes). I would of course then affix antennas to these mounts. Does this idea have any merit? Is 2" steel conduit rigid enough to support weight at 28' above ground? Should I go to 3" pipe instead? The more I sit here and think about it, the more I think 2" just won't be thick enough to stay rigid in high wind. I live in southeastern Arizona, and the winds here to get a little high. But my major concern would be lightning. Also, at some point we will be moving, and I'd like to just be able to take the pole, remove it from its sheath, and simply have to dig and pour at the new house. Thanks for any comments or suggestions. |
#3
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Ummm, The best thing I used was a 21' top rail for chainlink fencing.
No welding the sections together and you get 2. They fit together like standard antenna mast. this way with 2 feet in ground, you will have 40' over mast. Get some good guy wire and guy down 8' from the tip of the mast and then mount your pizza box above the guy wire coupling. this way one of the antennas can still go at the tip of the mast. Hmmm... Good idea for the mast material, but the guy wires are out (not a lot of land back here at the corner of the lot where the house is). I may look into the fencing thing. Thanks. What's going to happen when my tower is struck by lightning? If its proprely grounded, do I have to worry about the bolt lighting my house on fire, blowing up my scanners and radios with me in front of them, etc? |
#5
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![]() "Jason Wagner" wrote My fathers own an electrical supply warehouse so I have access to steel conduit at cost. As far as I know, conduit isn't rated as a structural member... Does this idea have any merit? Is 2" steel conduit rigid enough to support weight at 28' above ground? I have three sections of 10' mast up, supporting a discone; it's scary to watch it sway around in a high wind, but it's held up. It's not conduit, though. My brain is trying to tell me that conduit won't take the necessary flexing....you might want to look into that. --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.507 / Virus Database: 304 - Release Date: 8/4/2003 |
#6
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I have three sections of 10' mast up, supporting a discone; it's
scary to watch it sway around in a high wind, but it's held up. It's not conduit, though. My brain is trying to tell me that conduit won't take the necessary flexing....you might want to look into that. Robert, What is your mast made of and how is it supported? Thanks. |
#7
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Wall clamps ... it all depends on how high your house is at the peak ...
"Jason Wagner" wrote in message ... I would like some opinions from you experiencd folks as to an idea I have for putting up an antenna mast. My fathers own an electrical supply warehouse so I have access to steel conduit at cost. Many years ago we used 4" conduit and elbows to build a basketball backboard pole in my folks' back yard, and the thing has stood the test of time, weather, and a generation of kids hanging from it. I have a similar idea for an antenna mount. I would like to dig a hole on the side of my house, approximetely 24" deep and 12" square. I'd like to take 12 2" conduit couples and weld them into a sheath, and then put this sheath in the hole, filling it (the hole) with cement. So I'd have a big cement block in the ground with a hollow tube in the middle. I would then take three 10' lengths of 2" conduit and weld them together using couples, and place the resulting pole into the hollow sheath in the cement. I would then use a pipe fastener strap to fasten the pole to the awning of the house, approximately 9' up from the ground. I'd pound a couple of copper lightning rods into the ground several meters away, and ground the pole to these rods with large-guage copper wire. So I'd have a grounded 28' pole above ground, anchored in a 24" deep steel sheath in the ground, and anchored at 9' to the side of the house with steel and bolts. So I'd have 21' of 2" steel conduit sitting in the air unsupported. I would then build some antenna mounts out of 1" conduit (something that would look like those little plastic tables that the use to keep the cardboard off of pizzas in their delivery boxes). I would of course then affix antennas to these mounts. Does this idea have any merit? Is 2" steel conduit rigid enough to support weight at 28' above ground? Should I go to 3" pipe instead? The more I sit here and think about it, the more I think 2" just won't be thick enough to stay rigid in high wind. I live in southeastern Arizona, and the winds here to get a little high. But my major concern would be lightning. Also, at some point we will be moving, and I'd like to just be able to take the pole, remove it from its sheath, and simply have to dig and pour at the new house. Thanks for any comments or suggestions. |
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