Stupid antenna question

[w3bny]

Ok you wheezles... Todays stupid antenna question.

Background data: Stupid bunnies at Lapin labs (of which, I am chief experimentalist ) are getting ready to launch a balloon lift antenna but one thing confuses me. To use radials or not.

My thought, its a vertical antenna and the performance is going to be poop if I dont use them. Research online that I have been doing shows them and kite lifted antennae as NOT using them at all. Yeah, I know the answer would be to pump it into EZNEC and see what the numbers say but alas...ahm too broke to pay for it!

So any of you guys that have used balloon/kite lifted antenna, your radial thoughts are welcome.

[NQ6U]

Make it a 1/2 wavelength antenna and you won't need radials, maybe just a short counterpoise. Shorter than 1/2 WL, though, and you'll need some sort of radial system.

[ab1ga]

I remember two articles about balloon lofted antennas in QST over the years.

The first was a club at Ohio State University; they used kitoons (blimps with fins) they got through military surplus to loft a 160m vertical antenna.
They did in fact use a "counterpoise" - "Big Ear" - the radio telescope at OSU, which was basically a sheet of copper the size of a footbal field.

The second article was in QST within the last five or six years. That Field Day group didn't use a vertical, but a loop antenna, I believe diamond shaped, fed at the bottom. This antenna obviously needed no ground plane, but the guying was more complicated because it had to retain at least a little bit of shape. I'm sure you'll be able to find an aging sailor who knows his way around rigging to take care of this for you. :-)

You could also look at variants of the end-fed Zepp antenna. Originally designed for use aboard, you guessed it, Zeppelins, it requires no set of radials, but since you want to feed it from the ground, you'll have to deploy it "upside down".

Regarding antenna modeling software, you may want to look at 4NEC2, which the last time I checked was free. Written by a Dutchman, so what could go wrong?

73,

[WØTKX]

Most use a vertical, but a circular polarized antenna would help. We have a very active balloon group here.

Rob the prez is a buddy of mine. http://www.eoss.org/

[kd8dey]

Curiosity, Hf Vhf Uhf??

[W5RB]

Do use a bleeder resistor at the base . The potential for static buildup is great .

[KG4CGC]

Do you have a groundable antenna tuner for a longwire?

[w3bny]

Curiosity, Hf Vhf Uhf??

HF of course. I could be stupid and try 6m but it would be the wrong polarity and if I am not mistaken would be looking at what...+/- 70db of loss right off the git-go?

Do use a bleeder resistor at the base . The potential for static buildup is great .

Good Gawd yes! I acquired another ICE Supressor just for that purpose. Mr. Coulomb has a big potential for lulz with balloon and kite antennas...many thousands of lulz.... Seriously, I will be using snap hook on the wire as the balloon/kite pays tied directly to ground out then when I hook up to the radio it will go thru the ICE for the surge/bleed.

Do you have a groundable antenna tuner for a longwire?

Yeah, planning on using a remote MFJ auto-tuner that I acquired as payment for services rendered..(OY-OY!! clean thought you bastridges!)

I have enough, well, more than enough copperweld to take care of a full wave antenna on 160 (or more) but will keep it at or under a half just for the counterpoise/radial issues and to keep myself out of trouble with the FAA!

[ab1ga]

Mr. Coulomb has a big potential for lulz with balloon and kite antennas...many thousands of lulz....

You ain't kidding. Ben Franklin was chugging along like gangbusters until he did that experiment with the kite, and then he came up with the idea for Daylight Savings Time!

[w3bny]

Doing some more google crunching... It looks like I am going to shoot with a 5/8th wave. Best low angle, shouldnt need radials or a counterpoise like the 1/2 wave should (even though its like .05wl). But, will definitely have make a loading coil to help cancel some of the reactive component. And a nice air wound coil I gots.

More later!