HF antenna selection help needed

[sloop]

I Have recently moved into a HOA. I am use to wire antennas but there is not enough room (land) to put one up outside (plus restrictions). So I am limited to an attic antenna. The attic has the heat and hot water systems (and Gas lines) which makes it not practical to run a wire antenna. I do have one end that is free of pipes and wires. I have narrowed the search down to the HVU-8 and the Isotron antennas. Does anyone have any thoughts on which one is better?

 

[prcguy]

Both antennas mentioned are dummy loads. If the walls and roofing material are transparent to RF you might consider lining the ceiling joists in the attic with as much chicken wire as possible for a ground plane and sticking an efficient HF screwdriver antenna in the middle. You can also replace the whip on a screwdriver antenna with a short wire leading to a large capacity hat made of wire tacked to the rafters.

Avoid small inefficient screwdrivers like the Yaesu ATAS and go for something like a Tarheel 100A-HP or a big Hi-Q version, both which can be had for good prices used.

I Have recently moved into a HOA. I am use to wire antennas but there is not enough room (land) to put one up outside (plus restrictions). So I am limited to an attic antenna. The attic has the heat and hot water systems (and Gas lines) which makes it not practical to run a wire antenna. I do have one end that is free of pipes and wires. I have narrowed the search down to the HVU-8 and the Isotron antennas. Does anyone have any thoughts on which one is better?

 

[popnokick]

Is there a reason a loop antenna suitable for transmitting (such as the MFJ-1788, Icom AL-705, or others) will not work in an attic?

 

[sloop]

I realize that I am asking for a solution to 'better then nothing', I considered a mobile antenna but I found that it would be no better than the other two plus I had the grounding problem that I did not have with the others. A loop antenna would possibly be the best option, but I need access to 80 meters at 100 watts not QRP. I really don't want to spend $900 for a remote tuning (necessary because of location) for an antenna (wife would kill me).

 

[ka3jjz]

Do you have enough room in your attic for this?

Ever hear of the Broadband Butterfly Terminated Dipole?

Supposedly very wide band, and if you have a good sized attic like the individual in the video, this might be for you if you're stuck with condo nazis. Unfortunately BuxComm is gone (I think he closed his doors a year or two ago). Mike

forums.radioreference.com

Mike

 

[ka3jjz]

I kinda suspect this might be nothing more than a cloud warmer, but....

My Go2 Antenna — TN07

My Go2 Antenna is specifically designed for HOA owners and portable / Emergency communications operations. HF antenna - operates on 80-6 meters 3.5 - 55 MHz; SWR ≤2:1 no antenna tuner required. Supports ALE & frequency hopping - no re-tuning!

tn07.com

Mike

 

[prcguy]

I can guarantee a large screwdriver like a Tarheel 100A or 5" coil or larger Hi-Q will work better than your two examples and the TN07 mentioned above. If you can line the attic with chicken wire you don't need any other ground because that would be the ground plane for the antenna and there is no lightning requirements being inside the attic.

The big screwdriver antennas work very well on vehicles and you can have many times more ground plane in the attic making them work even better.

I realize that I am asking for a solution to 'better then nothing', I considered a mobile antenna but I found that it would be no better than the other two plus I had the grounding problem that I did not have with the others. A loop antenna would possibly be the best option, but I need access to 80 meters at 100 watts not QRP. I really don't want to spend $900 for a remote tuning (necessary because of location) for an antenna (wife would kill me).

 

[sloop]

PCguy, I had thought about that, but I do not have 'permission' to place an antenna outside (yet). As far as inside think of a rectangle with one corner having the heat system, the opposite corner the hot water system, and the third corner the gas piping and electrical connections. I have one 'free' corner and unfortunately it is only a little over 9 feet at the apex (the Tarheel 100A is 11' 4" at 80m). Other than 2 foot wide walk ways there is about 3 feet of insulation over the rest of the attic. I appreciate the thoughtful suggestions but I have about decided to forgo any HF until I get permission for outside antenna. If I do then comes the other problem of where to put it (think of a house with the same yard as one in Los Angeles, LOL).

 

[TomLine]

What kind of roofing material is used? ARRL magazine had an article about guys in florida with concrete tile roofs and concrete stucko walls having good luck with roof wires. A myantennas EFHW has a very skinny black wire one could hook from the roof to the trees way out back away from prying eyes. Perhaps a shared rig, accessed over the internet would be the way to go.