Survivalism & Self Sufficiency Topics > Amateur Radio How-To's

The FAN DIPOLE,an EASY, EFFECTIVE HF Antenna

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Carl:
The Fan Dipole is often way over-built with todays automatic antenna tuners (and manual tuner ,for that matter) a  multi-band antenna need not look like a NASA radio installation. All you need to build a 6 through 40 meter antenna is 110 feet or so of wire ,insulators (made from PVC pipe ) and a 1 to 1 BALUN / Feed Point where it all comes together...Plus a bit of rope (black 550 para cord is my choice).

The balun is a transformer that helps to keep your radio from interfering with other electronics and you will find it worth the $20 to $30 you spend. It also handles the two wire antennas and coax connections. The common feed point should be up 20 feet or so ,hung from a pole,tree or tower,or even rooftop. with the two antennas sloping down to a lower (but still above head level) support at the ends with a bit of rope and insulators to do the job. My antenna has slim 10 ft sticks of conduit stuck in the cyclone fence for it's end supports though I do have a tower finally...the original middle support was an 18 foot aluminum pool cleaner/skimmer pole and I still have it.

A picture is worth a few words here:



and with these TWO dipoles ,I work 80 ,60,40,30,20,17,15,12,10,(whew!) and 6 meters with only a 3 to one tuner in my radio. Though I suggest a better capable range tuner like most any LDG tuner and a 4 to 1 Balun for your widest range of antenna use. My antenna was made from an extension cord that was put to the curb after a neighbors hedge trimmer incident and some PVC with the only real cost being the Balun that cost only $16.95 back in the day.

NOTE that I chose 20 and 40 meters as they are my favorite bands and I see little need to add other wires cut for other bands that my tuner can already deal with...what I give up in efficiency I make up for in ease of install and operating time. If you feel the need to TUNE each band buy cutting(and this can help) PLEASE cut the lowest frequency first (longest wire pair) and remember that there is a bit of inter-action between the wires ,so cut carefully...if you must mess with it.

Happy Hamming!

Smurf Hunter:
Regarding the baluns, there are several 1:1 options available in that price range.

What if any functional difference is there between a direct copper wire connection and just using the eye hooks?





Or, can you specifically recommend a balun?

Carl:
I much prefer HOOKS to tie to and wires to solder to ...The hooks only option tend to loosen in the wind and don't offer much of an electrical connection. Mine is an earlier version of  the MFJ  that used threaded contacts and eyelets and has been in service many years...You tie your wire to the eye hook for strength and solder the wires for good electrical connection . The coax should not hang on the connector and should be weather sealed ( I use self vulcanizing tape AND PVC tape over the SV tape) Also you are welcome to steal my idea of the pulley and para-cord as it has saved a lot of climbing . Photo shot minutes ago and it was 25 feet up and a bit farther from me ,sorry focus is not so good.




FreeLancer:
How close together can the ends of each band be to each each other?  I'm assuming more distance is better.

Carl:

--- Quote from: FreeLancer on January 06, 2015, 01:25:24 PM ---How close together can the ends of each band be to each each other?  I'm assuming more distance is better.

--- End quote ---

I have had different wires within 18 inches of each other and needed wires about 5% longer than for single wire/band due to interaction. But you tune the longest wire(lowest band) FIRST and work your way higher...if it matters to you that all is perfect.
In building one at a friends place we just cut all wires to the proper length and 'let 'er rip' with no real difference in performance. Many designs use as little as 8 inches separation( I even made a dual band with ladder line as the two bands) Remember that many HF bands are multiples of each other and you don't need 5 wires (like I started) I have just a 40 meter cut for 7.300 and a 20 meter cut for 14.070 (I love PSK) and work all the other bands (even 80 meters at a tad lower than max power) on those TWO WIRES. I know there are more efficient (like a wire for each band) options ,but that is for the folks who try to find that last percentage ,and I just want to have fun and operate.

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