Posted: 10/18/2010 6:55:04 AM EDT
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I know I've seen posts on Stealth setups, but a search is coming up empty. I've got a coworker that just got his tech and general, but lives in an apartment. He likes to talk radio, but has yet to get an HF antenna up. I told him I'd try to give him some ideas, as I've seen plenty of good ones on here before.
So... post info on your stealth setup. Greatly appreciated! |
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I suppose there are varying degrees of "stealth". I think of a "stealth" antenna as something which is permanently installed that doesn't look like an antenna (a flagpole, small gauge wires hidden among trees, etc.).
I am temporarily in an apartment and I have a small(ish - about 18'tall) vertical mounted on a video camera tripod on the back deck, with some radial wires suspended around the fence. I invested some time (but not a lot of money) in modifying a cheap commercial vertical and putting together the tripod system. But where I am there are no rules really being enforced and I can leave it out and up all the time - my limitations are mainly safety and the space available. I have the HF vertical on one side of the deck and a 2M Ringo about 10' up on the other side. I could hide them in about ten minutes but I don't bother - lest I not bother putting them back up! A person with a lot of money to spend could probably do better in a small space with one of the high-Q screwdriver type mobile antennas working against a counterpoise system, or perhaps a high-Q loop. The more run of the mill quick takedown portable antennas aren't much to write home about, but everything works to some extent. Finally, TVI isn't the problem it used to be but received noise on a close to the ground antenna is more so. |
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My stealth setup uses an SGC SC-237 auto tuner mounted outside and powered through the SGC Coaxial Line Isolator. One side is wired to an 8-foot ground rod. The other side is connected to military field phone wire that runs up my house for 8 feet, then runs horizontally for about 50 feet over to my daughter's swing set. From outside the yard, you can't see the wire. This setup will work for NVIS propagation only, so you're limted to a 300-400 miles depending on a variety of factors. |
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Back in my college days, I had good results with a "stealth" random wire antenna outside my dorm room window. It was made of very thin stainless steel fishing leader wire (not the best for conductivity, but very strong and unobtrusive), and ran to a streetlight approx. 80 feet away from the dorm window. It was tuned with a home-brew version of MFJ Enterprises' MFJ-16010 random wire tuner The antenna ground/counterpoise consisted of another thin wire that was dropped out the window to the ground, 3 stories below.
Random wire tuners are very versatile in "stealth" applications. With a little ingenuity, they can be used to tune all kinds of outdoor metallic structures (if they're properly insulated) - rain gutters, flag poles, fences, metal patio umbrellas, etc. |
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Bigdaddy's set up is stealthy as heck. Raingutters have been loaded up. I even heard of a guy who was using a table lamp as a dummy load playing with his tuner and had a QSO.
A thin wire 23 feet long or longer as a vertical would be hard to see. Are there trees at you apt complex and are they close enough to string a random wire up? ETA I lived in an apartment once that had a metal handrail going from my second floor apt to the ground. I'd bet you could load it up with a tuner. Run it QRP so no one could get an RF burn. |
Yeah, I was going to chime in, but the apartment location probably wouldn't work with a Carolina Windom. The random wire, on the other hand, is a good bet to work. I have a 50' long 26AWG black insulated wire sloping to a 20' crappie pole that has reached from Indy to San Diego with 5w QRP phone. Something like that should work fine if there's a support nearby. That one needs a counterpoise, though. That small a wire virtually disappears. Big-Time stealthy. 
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Quoted:
There was a thread a little while back about someone using a loop antenna hidden inside a patio table or umbrella. That would be a good apartment antenna if a balcony was available. Doh! Table antenna It was my thread and I forgot it. 
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Quoted:
There was a thread a little while back about someone using a loop antenna hidden inside a patio table or umbrella. That would be a good apartment antenna if a balcony was available. 3rd floor with balcony. I showed him the link, and I tihnk he wet himself. |
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Most radiators less than a 1/4 wavelength for the lowest operating frequencies are basicly dummy-loads. (Hamsticks, etc). One viable avenue would be some configuration usin a Hi-Q brand antenna and the counterpoise and whip on a tripod or c-clamped to your balcony railing if you have one. http://www.hiqantennas.com/ The other would be an SG-230 antenna match with a loop. SGC maintains that one can operate on most bands using an 80' loop of wire in a loop or multiple turn loops. They have a very good 'Stealth Antenna' publication on their website. I have 2 of the SG-230's and they are pretty amazing critters. I am running one of them feeding an 80' random wire against a chainlink fence as a counterpoise. Works great. http://www.sgcworld.com/Publications/Books/stealthbook.pdf The SG-230 can also be used to feed a long whip antenna provided you have something sufficent to use as a counterpoise or groundplane. Keep us apprised.... |