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eHam Forums => Antenna Restrictions => Topic started by: KB3HJK on January 06, 2019, 03:31:13 AM



Title: HF from apartment balcony
Post by: KB3HJK on January 06, 2019, 03:31:13 AM
I am looking for some ideas for an HF antenna. I am on the top floor apartment of a 9 floor building, with a balcony. The balcony is open above, and has metal railings. There are no trees anywhere, and neighbors with balconies surrounding me.

I am considering an MFJ Loop, but don't like the idea I would not be able to scan the bands for signals due to the very high Q. I have a tripod and could possibly run an inverted V, but I don't think I can get it high enough to handle the required wire lenght.

Also, any thing hanging over the balcony is out, as well as attaching anything to the balcony. This seems like an impossible situation, aside from the loop. And yes, I have the Stealth Amateur Radio book and it's not helping my specific situation.

Thanks for any advice.

Kevin
KB3HJK


Title: RE: HF from apartment balcony
Post by: K5LXP on January 06, 2019, 07:20:28 AM

The balcony being open above I'd go "up".  Something along the lines of a Bravo vertical.  Does not require attachment to the structure and will be far and away more efficient than a small loop.

Mark K5LXP
Albuquerque, NM
 


Title: RE: HF from apartment balcony
Post by: KB3HJK on January 06, 2019, 08:27:06 AM
I'm on their website now. Very interesting antennas! It's funny, I have a Sigma-5 in my closet. I won't use that for multiple reasons....too high profile, too high up, and it is not as efficient as advertised. Bravo has one called Flower Power that I am going to investigate. I wouldn't even need to make an attempt to hide it!

Thanks, Mark. I didn't know anything about these guys.

Kevin


Title: RE: HF from apartment balcony
Post by: K5LXP on January 06, 2019, 04:03:01 PM
Sigma-5 ... not as efficient as advertised.

Does seem unlikely a vertical dipole a foot and a half off the ground would be 90% efficient.  But I have a predecessor to the Sigma line I use /P and have had very good results with it.  Guessing 9 stories up the Sigma 5 would do pretty well.

Quote
Bravo has one called Flower Power

That's one way to add capacity.  Hang some LED's off of it and really make 'em wonder what's going on.

Mark K5LXP
Albuquerque, NM
 


Title: RE: HF from apartment balcony
Post by: SIMON123 on January 06, 2019, 06:33:03 PM
For wide band scanning, how about separate receive and transmit antenna?

This uses loop and receive about 100 country weekly on pskreporter.info statistic
http://9v1rm.dyndns.org:8901/

also, an example, loop in HOA, https://www.youtube.com/watch?v=2TwqW5hQjR8


Title: RE: HF from apartment balcony
Post by: ONAIR on January 06, 2019, 10:12:25 PM
Use your tripod and a telescoping fiberglass pole, then attach an end fed antenna wire to the pole!  I have had good results using a 24 foot Ultimax-100 end fed in a vacation condo, both vertically on the terrace and horizontally inside the unit.  ( www.Ultimax-Antennas.com )  Check the reviews for this antenna right here on eham.   You might also want to try a end fed with a 9:1 unun, in a similar configuration.


Title: RE: HF from apartment balcony
Post by: KB3HJK on January 07, 2019, 06:35:21 AM
ONAIR - that's the way I am going to go. Just ordered the Ultimax-100. Now I just need to find a telescoping pole that will fit into my MFJ 1918 tripod and I'll be all set. After years of running a Sigma-5 on the ground floor courtyard, sandwiched by tall buildings, I think I just might hear the ham bands for the first time. Thanks everybody.

Kevin


Title: RE: HF from apartment balcony
Post by: KB3HJK on January 20, 2019, 04:44:32 AM
After one day on the air with the new Ultimax-100 I cannot overstate how happy I am with this. The NA QSO Party was going and I made contacts all over the country on 15, 20, 40 and even 80 with 60 watts. Two west coast stations went out of their way to say nice signal. Compared to my old Sigma-5 this just blows it away. I suspect having it mounted as a slight sloper on the 9th floor helps alot. I'll really get a feel for it if some dx starts coming through...I didn't hear any yesterday. Propogation is pretty bad these days. So...this is a great solution for my situation. I'm in shock.


Title: RE: HF from apartment balcony
Post by: KE6EE on January 20, 2019, 07:33:50 PM
the 9th floor helps alot

I have regular QSOs with a couple of balcony antenna stations. They are several hundred miles away and have reliably strong signals on 40M and lower bands. The antennas themselves may be marginally efficient, but the height makes all the difference.


Title: RE: HF from apartment balcony
Post by: NI0C on January 22, 2019, 10:32:27 AM
A member of our local DX club lives on the 17th floor of an apartment building near me.  He has a balcony on one corner of the building, where he has installed one of the MFJ loops (that goes down to 40m) and one of the Trans World vertical dipoles (pretty much equivalent to a Sigma 5) that covers the 20-10m bands.  He seems reasonably happy with the performance of both antennas.  Even though the MFJ loop has a narrow bandwidth (especially on 40m), it works out well on FT8.
 


Title: RE: HF from apartment balcony
Post by: ONAIR on January 26, 2019, 03:16:52 PM
After one day on the air with the new Ultimax-100 I cannot overstate how happy I am with this. The NA QSO Party was going and I made contacts all over the country on 15, 20, 40 and even 80 with 60 watts. Two west coast stations went out of their way to say nice signal. Compared to my old Sigma-5 this just blows it away. I suspect having it mounted as a slight sloper on the 9th floor helps alot. I'll really get a feel for it if some dx starts coming through...I didn't hear any yesterday. Propogation is pretty bad these days. So...this is a great solution for my situation. I'm in shock.
    As was I!  A 24 foot long antenna that even seems to work indoors?  I often take it with me on business trips and set it up inside hotel rooms.  It's definitely a good option for someone who needs a stealth antenna.


Title: RE: HF from apartment balcony
Post by: KD8NGE on January 27, 2019, 04:07:00 PM
 ;) As not infrequently happens --
The OP posts a question pertinent to his particular situation.
Many eyes read it, many minds consider their firsthand experience.
Replies are made, and as a result of multiple replies drawing on actual experience, more than the OP benefits!
Many thanks, my friends: although my attic fan dipole matches beautifully as far as SWR, so does a dummy load, and using my attic home brew is like delivering the Sunday sermon with a five gallon bucket dunked down over my head.
It don't work so terribly good.
I'll be trying that Ultimax.
I believe it will solve multiple problems and concerns!


Title: RE: HF from apartment balcony
Post by: VE3QTH on February 05, 2019, 02:16:09 PM
Hi Kevin, move!

Just joking. You will need to compromise because of your situation. Hi Q antennae are your best bet. ISO loop/Magnetic loops are expensive, narrow banded, directional unless mounted horizontally. MFJ have a few good ones, but they also have a few good balcony antennae, MFJ 1622/1623/1624/1625. Just remember Hi Q antennae carry very hi voltages at the fee point and typically you are very close to it and in the radiation pattern.

MFJ also has a nice artificial ground MFJ 931, good to tune a random length of wire as a counterpoise and save you having to get different length counterpoises swapped in and out.

You can also look at a Buddipole/Bobbipole option, or even mobile antennae like the OPEK HVT-400B . You will need about 23 feet of balcony and it will be directional, but the OPK HVT-400 mobile antennae can be mounted on a clamp-on mount. It can be set up so you just need to move the jumper up and down the coil and tunes easily.

Other compromise antennae my be a slinky antenna. The apartment height will make up for the limitations and get you contacts.

There you have it. Just remember most things in HAM RADIO communications involves compromises. You are in an apartment. The only thing that will get you a flat SWR across the most of the bands, be reasonably priced, and work in most modes, will be a dummy-load.

Or, you can always go QRP transportable and set up nice QRP system with a full sized antennae in a nearby park or field.

Good luck and 73
de Ve3qth   Robert







Title: RE: HF from apartment balcony
Post by: KB3HJK on February 06, 2019, 06:31:49 AM
Thanks Robert. I mentioned above that I settled on the Ultimax-100 and am very happy with it. I instinctively know it would destroy a Buddipole, and seems to be bearing that out in use.


Title: RE: HF from apartment balcony
Post by: N4TFC on February 16, 2019, 09:45:46 AM
Hi Kevin... I'm on the third floor of a concrete floor, brick wall, and metal framed condo. I do have trees right off the back with a feedpoint 35 ft up about 15 ft from the radio. Pretty nice compared to your situation. Don't forget to consider a mobile screwdriver antenna. I really really really almost went with a Hi-Q 6/160 before opting on using a wire in the trees. If Hi-Q weren't on extended holiday this year I prolly would have made the plunge. I had one many years ago and they do work well. Just 3 ft tall plus an 8 ft whip. You can put a foldover for the whip and set it out at a 45 to clear the ceiling or whatever. I was going to opt for an extra 2 ft mast to fit in better next to the 4 ft tall railing. You can also use a tripod and lean it a little to reach out. Counterpoise!!! - don't dismiss using the railing as a counterpoise. It's very easy to drill a little hole in that iron and attach a wire to get some bounce. You may also be able to extend that to the next railing with a wire jumper. I have 50 ft of 4 ft railings tied together. Also maybe coil a bunch of copper around the balcony. Pass it from window to window to get more length. Even attach to a 500 ft spool or something on the balcony. The more metal the better. All very stealthy and can be a lot of surface area for a reflective ground. So, maybe more options than we realize. Maybe give it some more time to get creative. Best of luck! … Roger N4TFC - Third Floor Condo


Title: RE: HF from apartment balcony
Post by: VE2OPB on March 31, 2019, 05:07:44 PM
hi look for my call sign on qrz.....
good luck
pierre ve2opb