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Attic Antennas with stucco house + concrete tile roof
Hi Everyone:
I am new to this forum, and haven't had a chance to search around much, so sorry if this has been discussed before, but I would like to know if anyone has experience putting up wire antennas in an attic where the house is stucco covered with concrete tile roof? I am wondering if the concrete roof tiles will have much of an adverse affect on HF frequencies? How about VHF & UHF?
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The concrete used for your roof likely has metal re-bar (or may have used metal mesh).
That will have an effect on RF.
w9gb
We keep moving forward, opening new doors, and doing new things, because we're curious and curiosity keeps leading us down new paths. -- Walt Disney
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I don't think concrete roofing tiles contain any metal at all. They are made of Portland cement, blended hydraulic cements, fly ash, sand, and other aggregates. Portland cement is transparent to RF but I don't know about the other ingredients. Stucco is applied over a wire mesh, so that should look like a good RF shield. An antenna close that that is likely to not work well.
Jerry, K4SAV
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I have a stucco walled house with concrete tile roof. The stucco walls are very effective at reducing and affecting RF signals due to the metal mesh within. The concrete tile roof should not pose a big problem methinks, other than the usual shortcomings of attic antennas.
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All of the houses in my neighborhood are stucco so If I can't put up a permanent antenna due to CCR's and have to use a portable / temporary mast setup, would I have to get the antenna above all the nearby houses so as not to affect it's performance? I guess doing an inverted V from the peak, sloping down to a fence in the yard might also have issues since it would have the stucco wall "shadow" as well?
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I used HF antennas in the attic of a stucco house that had concrete tiles on the roof. I had fun making CW & digimode contacts in spite of using fairly low power (because 100 watts caused RFI to every domestic electrical appliance). I made more contacts with a bit less RFI once I got an antenna installed about 1 inch above the concrete roof tiles. With that roof-hugging antenna, I could run 100 watts on most HF bands and I managed to complete WAS in a little less than one decade. Once I put an antenna high and in the clear at that same QTH, I was able to make many more contacts with greater ease (and distance) in spite of being at the bottom of the sunspot cycle.
Years earlier at another QTH, I had a 40 meter open loop around the ceiling of a ground floor apartment in a stucco building located in a canyon. QRP was necessary to avoid RFI to neighbors, but I was still able to make some 40-10 meter CW contacts and even a few SSB contacts. Sound card digimodes hadn't yet been invented, but I'm sure they would have worked from that location just as well (or better).
Bottom line, stucco and concrete roof tile won't completely kill your signal or your fun, unless your goal is to be competitive in contests or make DXCC. It is much better though, to go for the outside wire, get it as high as you dare, and you'll do better than with an attic or roof-hugging antenna.
Gary, K9ZMD
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Careful not to make old People mad.
We don't like being old in the first place, so it doesn't take much to piss us off.
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Don't forget the possibility of installing a very good mobile antenna system on your vehicle, park it outside, and run coax along the ground, behind bushes or whatever to hide it going into the house. Then, you just operate inside, with a decent antenna outside. The advantage of doing this is you can often park far enough away from obstructions that a good mobile antenna will easily outperform an indoor one, especially when dealing with stucco and other shields.
I have stucco siding here on my home, as do most people in southern California. Here's how VHF works through that: It DOESN'T. If I stand by a window, I can work a repeater 70 miles away. As soon as I step away from the window, so I'm shielded by the stucco, I can't even tell that repeater is there, let alone work it. If I step outside (same HT, same whip), it's full quieting, just standing in the driveway at ground level.
The "difference" is 30-40 dB, maybe worse.
I have no restrictions here, so of course I have towers and outside antennas. But I use the "HT" example because it's fun to walk around and chat on VHF sometimes, and indoors with stucco, unless I'm near a window, that doesn't work at all.
When I had a stucco tri-level town house 20 years ago (temporary), I tried attic dipoles and installed three of them for HF work. They could make some contacts and "sorta" work. But when I put a big mobile whip on the station wagon, parked it outside, and ran coax into the rig -- what a difference! It worked at least 10 dB better than full-sized attic dipoles did, and also eliminated all the interference I was causing to smoke detectors, telephones and other stuff inside. Perfect compromise: Less RFI and better performance, all in one. Just by using a good mobile system.
For that, I had a perfect setup because I could park outside about 60 feet from the garage door to the town house, and run RG8X coax behind bushes all the way to the garage door, where the coax simply ran under the door and into the town house. When I needed to use the car, I'd just disconnect a coax splice behind a bush, pull ten feet or so of coax into the car, toss it inside and drive away. Whole setup or breakdown took maybe 20 seconds.
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Now that is a very interesting idea. I recently bought a Icom 7000 and a Little Tarheal II for my car so I can do mobile HF and UHF/VHF while driving to and from work. I have a Kenwood TS-440 and a TS-570D that I want to set back up in the house and have been trying to figure out how to get my Cushcraft R5 up in a way that is portable so I don't run into CCA rule issues. Using the car antenna might work.
My house backs up to the edge of the housing development but I have overhead electrical lines on the street behind my home. Trying to figure out the best way to get back on the HF bands. Would dipoles "hugging the roof" have to be at the peak or could they be just above the gutters if I put up suspension poles a few feet above the eve but below the peak where no neighbors could see? Problem would be they would be parallel to the next streets electrical lines and about 20 ~ 30 feet away horizontally.
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 Originally Posted by KG6OJO
Now that is a very interesting idea. I recently bought a Icom 7000 and a Little Tarheal II for my car so I can do mobile HF and UHF/VHF while driving to and from work. I have a Kenwood TS-440 and a TS-570D that I want to set back up in the house and have been trying to figure out how to get my Cushcraft R5 up in a way that is portable so I don't run into CCA rule issues. Using the car antenna might work.
My house backs up to the edge of the housing development but I have overhead electrical lines on the street behind my home. Trying to figure out the best way to get back on the HF bands. Would dipoles "hugging the roof" have to be at the peak or could they be just above the gutters if I put up suspension poles a few feet above the eve but below the peak where no neighbors could see? Problem would be they would be parallel to the next streets electrical lines and about 20 ~ 30 feet away horizontally.
Have you tried using the mobile antenna, but from inside, with a coax extension? Could be the answer to all your issues.
And there are way better mobile antennas than the Little Tarheel II. I have a Hi-Q 5/80 which admittedly is a lot larger than the Tarheel and requires a more substantial support, but it can work about as well as a full-sized home station vertical if it's installed well, and nobody could say you're violating any covenants (if outside parking is allowed overnight there).
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Another idea for an outside antenna: run a loop of wire around the eaves of the house. Can be almost invisible to neighbors.
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