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simple homebrew HF antenna for an apartment

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by KD5HQN, Nov 7, 2009.

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  1. KD5HQN

    KD5HQN Ham Member QRZ Page

    hey all, I have been searching through the forums as well as the web and have come across alot of ideas, but I would like some direct input as well... I live in a small 1 bedroom apartment on the second floor of a two story apartment building. I am looking for a simple HF antenna that I can build to get me on the air. It will need to be something that I can use without a tuner, and will be used with an Icom IC-725. I don't mind building and using separate antennas for each band. I do not have a balcony, and as of yet, no roof access. these will probably have to be something I can string up in a few minutes from my windows and take down when I am not using them.

    Any ideas are greatly appreciated. criticism, if constructive is also appreciated. However!!! If you are simply going to tell me to put my favorite hobby on a back burner until I can get into a "proper" housing situation for a ham, do not bother to post.

    Thank you!!

    Jeremy
    KD5HQN
     
  2. KJ6CEA

    KJ6CEA Guest

    you can try draping out a sort or whip out of the window and use it at lower power.

    you could try a clamp to and use firm wire and make a vertical farther away from your house.

    the farther you can get it away from anything the better it would do, expect better signals from the facing angles.
     
  3. KD5HQN

    KD5HQN Ham Member QRZ Page

    getting it away from the building is not an option... no trees or anything to hang it from...
     
  4. N3UJM

    N3UJM XML Subscriber QRZ Page

    Some sort of whip or hamstick out the window. Tie a sinker to some 22G wire and lower it out the window for a counterpoise.

    I have thumb-tacked a dipole to the inside of the walls. Don't expect much but it's better than nothing.

    I once lived in an apartment with "no roof access". I went up at night and ran a wire along the peak and ran it into my window. Could not see it from outside. Required a tuner.

    If you have a PVC vent pipe from your drain to the roof...I'm thinking of some creative options.

    Tom
     
  5. KD5HQN

    KD5HQN Ham Member QRZ Page

    I think that if I could get onto the roof, that would be a good option, it is a flat roof... but I don't know of a way to get up there... I was thinking of making a couple dipoles for the bands I plan to work and using some of those plastic spring clamps to hang it from the metal roof trim... one as far as I would reach out my bedroom window and on as far the other way as I can reach out the living room window (the are both on the same side of the building) and letting the ends of the dipole hang down, sort of inverted L's. then running coax from the center in the window to my radio. I don't have a tuner, and can't afford one unless I can find it really cheap... there is a hamfest close to me tomorrow morning, so I might go and see what I can find... don't have very much of a budget, but I might be able to snag something on the cheap...
     
  6. KJ6CEA

    KJ6CEA Guest

    I know that feeling. ask you tenant if you can get on the roof, you might get lucky and find a pole up there to make a inverted v or sloped. Keep in mind that tuners might not work as much (i have heard bad things about yaesu tunners) or as well as you would like, so make it as resonant as you can (the longer the better to for higher frequency's.
     
  7. KB1ORM

    KB1ORM Ham Member QRZ Page

    KD5HQN:
    My experience is somewhat limited but what kind of tuners have you been looking at? MFJ makes a "Travel Tuner" that sells for about $100 new and a larger unit that goes for about $150. Neither is in the same league with some of the automatic tuners on the market but they seem to do the job. You can likely find one at a hamfest (or maybe on the "buy and sell" side of this forum). for quite a bit less.

    73 and good luck!
     
  8. N4OGW

    N4OGW Ham Member QRZ Page

    Once in a similar situation in an apartment, I just ran a horizontal loop of wire around the top of the wall in the bedroom. Held up with thumbtacks. I'd guess it was a full wavelength somewhere around 20m. I did use a tuner to feed it.

    It wasn't super, but I was able to make some contacts. I had to keep the power pretty low to avoid causing RFI.

    Tor
    N4OGW
     
  9. WE6C

    WE6C Ham Member QRZ Page

    I also used a loop tacked to the walls inside a bedroom. Just like OGW it worked ok and I could make contacts. I fed it with ladder line then a balun, then coax to a rig. If you play with the lengths of the loop and feed lines you can probably get close to a decent SWR somewhere but a tuner will really do the trick. If you're good with the smith chart you can figure out feed line lengths and/or use matching stubs.
     
  10. KD5HQN

    KD5HQN Ham Member QRZ Page

    thanks for the Ideas, I have been looking mostly at the MFJ tuners. autotuners are out of my price range, but I have several of MFJ's tuners on watch on ebay (yes, ebay) that have a few days left on them and are currently under or right around $100. depending on what my necessities for the next two weeks run me when I go shopping today, I may be able to swing one of them.
     
  11. N3UJM

    N3UJM XML Subscriber QRZ Page

    I got one of my MFJ tuners off ebay a couple years ago. Since then I bought a new one for another station. Nothing wrong with them at all. They'll tune in a wider mismatch than most autotuners. Takes time to experiment with the settings, but once you write them down for each band segment, it takes only seconds to return to them.

    Tom
     
  12. KI6J

    KI6J Ham Member QRZ Page

    N2LK tuner

    In the homebrewing section N2LK posted his L-tuner project. Such a unit shouldn't set you back more than a few dollars and an afternoon. It would enable you to get a wire or whip out the window tuned up.
     
  13. KD5HQN

    KD5HQN Ham Member QRZ Page

    thanks for the vote of confidence in the MFJ tuners. Also thanks for the info on the tuner project, I will look into that and see if I have or can get the necessary parts to build one.
     
  14. KD0ANV

    KD0ANV Ham Member QRZ Page

    I'm overcoming a similar problem in a townhouse. I have a tacked-up 10m dipole, and a tacked-up 20m Inverted L. On the L, I've been making easy contacts to Washington State and Vermont running PSK on 14.070 with only about 20 watts.

    Today, i was making a supply run to the local ham radio store, and I got into a discussion with one of the gentlemen who works there. He was saying a few locals have had good luck in a similar situation with the Opek HVT-400B. It sounds like it takes some initial setup, but once you find the sweet spot for each band, it's pretty usable. Counterpoise requirements are seemingly fairly minimal. I'm thinking about getting one with a magnet mount and sticking it to a large metal work bench I have. Happily, the cost is reasonable, and even more reasonable if it can be found 2nd hand.

    The reviews on eHam aren't stellar, but most of the complaints stem from mobile use, which mine won't ever see.

    If you try it before I do, I'd be interested to hear your results! Anyone else?
     
  15. W0IS

    W0IS Ham Member QRZ Page

    From hotel rooms, I've used a similar approach to what this guy did:

    http://www.arrl.org/news/features/2008/06/04/10144/

    In this example, he is using a tuner, but that's not really necessary. You can do the same thing running an inverted vee dipole out the window. You might need two sticks, but you can probably get by with one.

    Basically, have a stick poking out from the window. Run the wire out to the end of the stick, and then just flapping down into the wind. You can even have it drape down from the stick so that you can get a few more feet out there. 40 meters might be tricky from a second floor, since each wire would be 33 feet, but I bet if you were creative, you could figure out a way.
     
  16. WD5BOA

    WD5BOA Ham Member QRZ Page

    When I lived in an apartment, I built a cobbweb(sp) antenna and hung it from the ceiling. I made it from 3/4" pvc and speaker wire. I built it for 10-20 and it did quite well. I was pleasantly surprised. All you need is a room abour 10'X10' and a ceiling fan (or some other method) to hang it from.
     
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