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Cheap, Light-duty, Freestanding, Antenna Tower??
Where can I find an inexpensive, freestanding (or lightly guyed), antenna tower? It doesn't have to support a lot of weight - a couple of small 2m radio antennas and one or two scanner antennas. And it also doesn't have to be very tall - thirty to forty feet would be just fine. I'm sure others would be interested in this also. Dwight Stewart (W5NET) http://www.qsl.net/w5net/ |
"Dwight Stewart" wrote in message .. . Where can I find an inexpensive, freestanding (or lightly guyed), antenna tower? It doesn't have to support a lot of weight - a couple of small 2m radio antennas and one or two scanner antennas. And it also doesn't have to be very tall - thirty to forty feet would be just fine. I'm sure others would be interested in this also. Dwight Stewart (W5NET) http://www.qsl.net/w5net/ If they still make it, the Rohn HBX series would be the least expensive. (Notice, I didn't say cheap). It comes in 8 foot sections that bolt together. The top section is the skinniest, about 6 in on a side, and sections get progressivly larger towards the bottom. It is light enough that one person could lift a 32 foot tower. Good for 10 sq. ft. of antenna. Self supporting, if you mount it on a concrete base. Another low end tower is the USTower MA40. This is a tubular crank up tower with a hinged bottom. You either need their raising fixture (expensive) and a concrete base, or support it at about 8 feet against a building. It comes with the building support bracket; this method only requires a few bags of concrete. Also rated at 10 sq. ft. of antenna.. With this tower the rotor can not be mounted inside the tower, and you can not use a thrust bearing. If you live in a fringe TV area that recently got cable, you should be able to get a TV tower for free if you take it down. The ones I see in South Jersey seem to be 40 - 50 feet. Tam/WB2TT |
Radio Shack's telescoping masts work well and are cheap.
Do you need to climb it? jw wb9uai |
In message , Dwight Stewart
writes Where can I find an inexpensive, freestanding (or lightly guyed), antenna tower? It doesn't have to support a lot of weight - a couple of small 2m radio antennas and one or two scanner antennas. And it also doesn't have to be very tall - thirty to forty feet would be just fine. I'm sure others would be interested in this also. I have a 25 ft pole made of plasticised paper, in 4 sections, with brass inserts at each end. Ex-army. I paid 5 GBP (nearly a week's pay) for it in 1953! I used it guyed with light plastic line. It supported a 10 ele 2m beam for several years. Mike -- M.J.Powell |
"Dwight Stewart" wrote in message .. . Where can I find an inexpensive, freestanding (or lightly guyed), antenna tower? It doesn't have to support a lot of weight - a couple of small 2m radio antennas and one or two scanner antennas. And it also doesn't have to be very tall - thirty to forty feet would be just fine. I'm sure others would be interested in this also. Dwight Stewart (W5NET) http://www.qsl.net/w5net/ Go to your hardware store and buy a Aluminum ladder. Clamp it to the side of the building and guy as necessary. Just an idea. Dan/W4NTI |
"Dan/W4NTI" wrote:
Go to your hardware store and buy a Aluminum ladder. Clamp it to the side of the building and guy as necessary. As described in a previous message, there isn't a lot of room for guy wires. The area is about two and a half feet wide - just enough room for a cement slab to support a small freestanding tower. After that, there just isn't any room to run guy wires out very far. What there is (the building and a nearby fence) isn't going to provide a strong support for guy wires. Dwight Stewart (W5NET) http://www.qsl.net/w5net/ |
"Brian Kelly" wrote:
A shallow concrete slab will not support any tower unless the tower is well bracketed to the house. There are only two choices: A large block of concrete for the base or a slab with a house bracket. The word "slab" was probably a poor choice. I was mainly referring to the width, not depth, of the concrete. The concrete will pretty much fill the entire hole below the ground surface. Use a mast made from steel pipe. I've used 'em several times, works fine. Assume the bottom section of the mast is made from a full length of standard 2.5" Schedule 40 galvanized steel pipe x 21 feet long. Top the base section with a couple 10-12 foot lengths of smaller diameter pipe and assemble the mast & antennas. Drive a five foot length of 3" pipe into the ground, clean it out, raise the mast to a vertical position and drop it into the 3" pipe. (snip) To make it freestanding, one would have to use some fairly thick steel pipe (both wall thickness and pipe diameter), especially for longer lengths. And pipe that heavy would almost require a crane to move it around. Because of that, steel pipe might be fine for shorter masts (or guyed taller masts using thinner pipe), but wouldn't really be feasible for a taller freestanding structure (unless one owned a crane, but then the crane itself could just be used to support the antennas). Dwight Stewart (W5NET) http://www.qsl.net/w5net/ |
"Crazy George" wrote in message ...
Brian: You should mention to telescope the sections, rather than using threaded reducing fittings, which are not strong enough for this kind of application. Out of curiosity, how much overlap do you use? I've done it both ways depending on a lot of variables. I noramally do use threaded pipe reducers. As long as they're either steel or wrought iron that is. The cheap hardware store cast grey iron reducers are non-no's. I retap the reducers to get more thread engagement length. It's been demonstrated that Schedule 40 pipe will fail in bending before decent reducers fail. But in situations where the loads get dicey and/or parts of the mast are tubing vs. pipe I use at least six inch overlaps and have the joints welded. -- Crazy George w3rv |
"Dwight Stewart" wrote in message .. . "Tarmo Tammaru" wrote: If they still make it, the Rohn HBX series would be the least expensive. (Notice, I didn't say cheap). It comes in 8 foot... (snip) Yep, that's the best I've found so far. Dwight, My first tower consisted of 3 sections of Rohn HBX. This gave me 24 feet. To the top of this I added a 10 foot piece of 2 inch OD Al pipe. This was fastened to the tower with angle iron and U bolts at the top plate and the rotor shelf. Somebody gave it to me. It actually started life as a Hygain vertical. The middle of the second section was fastened to the end of the garage with TV house brackets. The ground mount consisted of three pieces of pipe driven into the ground, with 1 bag of concrete to add some strength. BTW, have you considered a roof tower? Even a garage roof would give you at least 12 free feet. Tam/WB2TT |
Dwight Stewart wrote in message ...
"Brian Kelly" wrote: A shallow concrete slab will not support any tower unless the tower is well bracketed to the house. There are only two choices: A large block of concrete for the base or a slab with a house bracket. The word "slab" was probably a poor choice. I was mainly referring to the width, not depth, of the concrete. The concrete will pretty much fill the entire hole below the ground surface. OK. Use a mast made from steel pipe. I've used 'em several times, works fine. Assume the bottom section of the mast is made from a full length of standard 2.5" Schedule 40 galvanized steel pipe x 21 feet long. Top the base section with a couple 10-12 foot lengths of smaller diameter pipe and assemble the mast & antennas. Drive a five foot length of 3" pipe into the ground, clean it out, raise the mast to a vertical position and drop it into the 3" pipe. (snip) To make it freestanding, one would have to use some fairly thick steel pipe (both wall thickness and pipe diameter), especially for longer lengths. That's nonsense. If you want a properly-designed pipe mast you do it by the numbers, not with amateur "eyeball structural engineering" and/or broad-brush statements like "have to use some fairly thick steel pipe . . ". You won't know a thing about any pipe sizes until and unless you run the numbers. A 40 foot pipe mast analysis is as simple as it gets in the field of applied mechanics, any sophomore student in any engineering discipline including the EEs who brought you your HT can handle the job. A pipe mast is just a classic cantilever beam. And pipe that heavy would almost require a crane to move it around. Because of that, steel pipe might be fine for shorter masts (or guyed taller masts using thinner pipe), but wouldn't really be feasible for a taller freestanding structure (unless one owned a crane, but then the crane itself could just be used to support the antennas). You gather up five buddies. You hang a pulley near the house bracket. Run a rope from the ground, thru the pulley then down to the midpoint of the mast. There's your "crane". Three guys walk the mast up and two pull on the rope and up she goes. Dwight Stewart (W5NET) http://www.qsl.net/w5net/ w3rv w3rv |
They don't work that well and they are not free standing! And they are
cheap because in 2 years they are so rusted you can no longer use it ;-( I've been there and done that, I wont do it again. Radio Shack's telescoping masts work well and are cheap. Do you need to climb it? jw wb9uai -- That Other George Please send your spam to: http://webpages.charter.net/moment/ http://webpages.charter.net/moment/winjunk.htm |
I bought a 30 foot tower from my local TV shop a few years back for $35.00
a 10 section. The company that makes it is American Tower I think they are in FL but a call to my local TV shop and he still sells the stuff only the price is now $41.00 a 10 foot section :-) It's free standing to 30 feet with a 3 foot X 3 foot X 3 foot base, or you can do what I did and stick 3 feet of the 30 foot tower in a 3' X 3' X 3' hole and fill it with quickcrete and run the garden hose on it for a few min :-) I used 2 U clamps to clamp it to the house in the middel of the 2nd section so my tower is good to 50 feet I'm told with a 6sq ft load Where can I find an inexpensive, freestanding (or lightly guyed), antenna tower? It doesn't have to support a lot of weight - a couple of small 2m radio antennas and one or two scanner antennas. And it also doesn't have to be very tall - thirty to forty feet would be just fine. I'm sure others would be interested in this also. Dwight Stewart (W5NET) http://www.qsl.net/w5net/ -- That Other George Please send your spam to: http://webpages.charter.net/moment/ http://webpages.charter.net/moment/winjunk.htm |
THIS PLACE MIGHT BE A START if you got the surfin time for searching
http://www.fairradio.com/0mk-12.htm 12 foot Military Mast Kit. Comes with: three 47" long x 1 3/8" fiberglass mast sections, one 8" top mast section which holds two horizontal arial antennas and also has 16 feet of RG-58 coax with a male BNC connection at the end, two 28" antenna elements that thread to the top section, one guy ring with guy rope, three 9" stainless steel stakes, one 27" long mast base which mounts directly into the ground, and O.D. green carrying bag with handle. There is no indication of a model number on the assembly. Excellent for field day or other portable antenna use. 12 lbs sh. #MK-12, $59.50 each; 2 for $99.50 yodar "Dwight Stewart" wrote in message .. . Where can I find an inexpensive, freestanding (or lightly guyed), antenna tower? It doesn't have to support a lot of weight - a couple of small 2m radio antennas and one or two scanner antennas. And it also doesn't have to be very tall - thirty to forty feet would be just fine. I'm sure others would be interested in this also. Dwight Stewart (W5NET) http://www.qsl.net/w5net/ |
"Tarmo Tammaru" wrote:
My first tower consisted of 3 sections of Rohn HBX. This gave me 24 feet. To the top of this I added a 10 foot piece of 2 inch OD Al pipe. This was fastened to the tower with angle iron and U bolts at the top plate and the rotor shelf. Somebody gave it to me. It actually started life as a Hygain vertical. The middle of the second section was fastened to the end of the garage with TV house brackets. The ground mount consisted of three pieces of pipe driven into the ground, with 1 bag of concrete to add some strength. Now that is a good idea. We could just add eight or nine feet of pipe to the top of maybe two tower sections. That would give enough height, without breaking the bank. However, the base would have to be stronger. We live in an area where tropical storms are routine and hurricanes are not rare. I don't really expect it to stay up through a hurricane, but would like it to survive most tropical storm winds. A solid concrete base, as described elsewhere, would be better suited for the task. BTW, have you considered a roof tower? Even a garage roof would give you at least 12 free feet. Yep, the roof is out. We're leasing the commercial building and they're very touchy about their relatively new roofing. Dwight Stewart (W5NET) http://www.qsl.net/w5net/ |
"Brian Kelly" wrote:
(snip) That's nonsense. (snip) Not in an area with relatively routine tropical storms and the occasional hurricane. Dwight Stewart (W5NET) http://www.qsl.net/w5net/ |
"That Other George" wrote:
I bought a 30 foot tower from my local TV shop a few years back for $35.00 a 10 section. The company that makes it is American Tower I think they are in FL but a call to my local TV shop and he still sells the stuff only the price is now $41.00 a 10 foot section :-) (snip) Not bad at all. I'll check around with some of the local TV shops. Dwight Stewart (W5NET) http://www.qsl.net/w5net/ |
They don't work that well and they are not free standing! And they are cheap because in 2 years they are so rusted you can no longer use it ;-( I've been there and done that, I wont do it again. Radio Shack's telescoping masts work well and are cheap. Do you need to climb it? jw wb9uai That's curious, I've had on problem with rust what so ever on any of the RS masts I've used (three total). I've got one on the roof now for 5 years, no problems. Bottom section is run through the access hatch, then bolted to attic floor. Holding a 5 el 6m beam and 11e l 2m beam. Rock solid through many big winds. jw wb9uai milwaukee |
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