Attic Antenna Suggestions?

Started by John Galt, November 23, 2013, 02:10:57 PM

Previous topic - Next topic

John Galt

I'm looking for some ideas for an attic antenna.  I currently only have an HT and a mobile rig.  I'm considering adding an all mode, all band HF rig for the house and as such will need to also add an antenna.
I know this will be somewhat of a compromise antenna but here are some of my constraints:

I have HOA restrictions so will need either a portable rig or, preferably, an attic application.
I have a 20x25 garage which is the only part of the house that doesn't have radiant barrier or other large metal systems such as HVAC components.
I intend to stay 100 watts or less for now.
Would prefer a single antenna to start so that I can at least play on numerous bands.  Maybe later I would consider a specialized application.

A couple products I'm considering are maybe a trapped dipole like the Diamond W8010.  I gets me a bunch of bands but at 63' it's going to have to bend around in the garage attic considerably.
Maybe a rotatable dipole like the Comet CHV-5X.  Again, it gets me a bunch of bands but there won't be a lot of room for rotation.
Or maybe a vertical like the Comet HVU-8.  At 8' tall it may not work but maybe something similar but shorter would.

Any discussion on the advantages/disadvantages would be appreciated.  I'm just looking for a good direction to continue my research.  Thanks!

KK0G

If I were in your shoes my priority would be to get the antenna mounted outside. As a general rule, even a crappy antenna mounted outside and clear of obstructions will be better than a great antenna mounted in the attic. A wire antenna made from 18 gauge speaker wire is very difficult to spot from even a short distance away, 28 gauge magnet wire is practically invisible.
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin

KK0G

John Galt

Quote from: KK0G on November 23, 2013, 02:29:37 PM
If I were in your shoes my priority would be to get the antenna mounted outside. As a general rule, even a crappy antenna mounted outside and clear of obstructions will be better than a great antenna mounted in the attic. A wire antenna made from 18 gauge speaker wire is very difficult to spot from even a short distance away, 28 gauge magnet wire is practically invisible.

That's gonna be tough but I'm all ears.  What about a wire along the gutters?  But I'm thinking that the gutter metal would be worse than the roofing material.  Running one higher along the roof is probably going to be too obvious to the HOA types.

gil

Check out http://thewireman.com, they have a great wire, #534, which is a 26ga copper clad steel. It is very hard to see and pretty strong..

Gil.

KK0G

Quote from: John Galt on November 23, 2013, 02:57:06 PM
That's gonna be tough but I'm all ears.  What about a wire along the gutters?  But I'm thinking that the gutter metal would be worse than the roofing material.  Running one higher along the roof is probably going to be too obvious to the HOA types.
Without being there to see what you have available in your environment it's going to be tough to recommend anything very specific. A center fed antenna might be tougher to disguise than an end fed because obviously you have a feed line in the middle of a center fed. But as I said, without being there I have no idea, maybe you have a simple way to hide the feed line behind a wall, tree, etc. End fed antennas such as an inverted L, EFHW, Zep, etc. work great and may be easier to hide in your situation. Running wires along side a tree to make a vertical could be an option. Does the communist HOA allow flagpoles? If so you could engineer a hell of a sweet vertical from that. If they don't allow them then it's your patriotic duty to inform them of their commie bastard ways (can you tell I'm not a fan of authority figures? 8) ).
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin

KK0G

John Galt

I've got a wood fence that runs from the garage that has some potential if I add some insulators to hold it.  There would have to be at least one 90 in it though.  So are we just talking a random length of end fed wire and then use a tuner to bring it to resonance?


Gil, thanks for the reference.  I'll be sure to check it out.

KK0G

Quote from: John Galt on November 23, 2013, 03:53:23 PM
I've got a wood fence that runs from the garage that has some potential if I add some insulators to hold it.
I assume you're talking about running it along the top of the fence? Unless the fence is at least 20 feet tall it probably wouldn't be high on my list of potential antennas.
Quote from: John Galt on November 23, 2013, 03:53:23 PM
There would have to be at least one 90 in it though. 
A 90 degree bend is not a problem, in fact in some antennas such as the previously mention inverted L a 90 degree bend is part of the design.
Quote from: John Galt on November 23, 2013, 03:53:23 PM
So are we just talking a random length of end fed wire and then use a tuner to bring it to resonance?
That's a definite possibility, random length end feds can work awesome. The other advantage is they're dirt simple and can be very simple to erect......... and hide. 8)




Keep in mind that almost every antenna is a compromise in one way or another, no single antenna will be perfect. Over the years I've learned from experience that for all intents and purposes on HF a wire antenna is a wire antenna is a wire antenna, seldom is there a drastic difference in performance until you start getting into directional gain antennas. As you're doing research to find what best fits your situation just remember these general rules that are usually true: higher is better than lower, in the clear is better than obstructed and longer is better than shorter.
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin

KK0G

John Galt

Quote from: gil on November 23, 2013, 03:00:28 PM
Check out http://thewireman.com, they have a great wire, #534, which is a 26ga copper clad steel. It is very hard to see and pretty strong..

Gil.

Oh yeah, Gil, that site's a keeper.  Bookmarked.

Thanks for the info, KK0G.  I'm gonna keep looking at my possibilities.  I've got a little time since saving for a new radio is a little slow going into the Holidays. 

BTW, I'm a born, bred and corn fed Iowa boy myself.  Born in Mason City, lived around the state and didn't leave until I graduated UI.  Don't miss the snow tho.

KK0G

Some links that may be of interest:


http://www.arrl.org/files/file/Technology/tis/info/pdf/0683033.pdf
http://www.hamuniverse.com/randomwireantennalengths.html
http://www.iw5edi.com/technical-articles/hidden-and-stealth-antennas
http://www.qsl.net/n5iw/ant.html


The 26 gauge Silky wire that Gil mentioned is great stuff, I use it for my portable end fed antenna. A source for very inexpensive antenna wire that's available locally almost anywhere in the country is speaker wire. Lowe's, Home Depot, Walmart, every corner hardware store and probably a thousand other places sell it dirt cheap. it's available in different sizes depending on how strong you need the antenna to be and you can either leave it as twin conductor or split it and get double the length. It's disadvantage is it can have more stretch than other wires but I've seldom found that to be a big problem.
"Those who would give up essential liberty to purchase temporary safety, deserve neither liberty nor safety" - Benjamin Franklin

KK0G

K8hid

What about your gutters as the antenna? I did that in the past in a restricted dorm setting. Used the the buildings water pipes as ground. You could lay 130 ft of wire on the ground around the house as a counterpoise.
Gary
K8HID

John Galt

Quote from: K8hid on November 26, 2013, 09:26:30 AM
What about your gutters as the antenna? I did that in the past in a restricted dorm setting. Used the the buildings water pipes as ground. You could lay 130 ft of wire on the ground around the house as a counterpoise.
Gary
K8HID

That's crossed my mind but I'm not sure how to go about it.  Would you feed the center conductor of the coax to the gutter?  And then where does the shield attach?  And how/where would you attach the counterpoise?   Sorry, I'm still new to this but I'm reading as fast as I can!

Lamewolf

Quote from: John Galt on November 23, 2013, 02:57:06 PM
Quote from: KK0G on November 23, 2013, 02:29:37 PM
If I were in your shoes my priority would be to get the antenna mounted outside. As a general rule, even a crappy antenna mounted outside and clear of obstructions will be better than a great antenna mounted in the attic. A wire antenna made from 18 gauge speaker wire is very difficult to spot from even a short distance away, 28 gauge magnet wire is practically invisible.

That's gonna be tough but I'm all ears.  What about a wire along the gutters?  But I'm thinking that the gutter metal would be worse than the roofing material.  Running one higher along the roof is probably going to be too obvious to the HOA types.

Just connect a wire from the metal gutters to a tuner and use them for the antenna ?  I've did that from motels before and worked all HF bands including 160 meters !

K8hid

I just hook it to the gutter anywhere and tune it up. You might want to make sure your gutters are electrically connected and not using the slip connectors. If they are a sheet metal screw in each joint will take care of that. If you want to message me i can talk you through it on the phone. 

Gary