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Permalink Reply by Morli on February 6, 2010 at 4:53pm

Yep , that will work too if low loss cable is used , infact such contraptions are used amateur radio. You may want to add inline amp also. But wind will keep the balloon pushed down wind or swing around which could be trouble. Why not use a tripod or even use simple fishing rod( 3-5 mt long) with antenna mounted on the top. Just anchor it or dig it in.

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Permalink Reply by Tim McMahan on February 7, 2010 at 12:51pm

That should work great, but yeah, there are simpler methods that might be more feasible. The most common is some sort of telescoping pole, mounted in a 5 gallon bucket filled with cement. You can also get fancy and put carry handles into the cement before it sets up. Then you can also add guy-wires via utility line and tent stakes. That's how my portable HAM mast is set up anyway. :)

KCØYOL
Tim

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Permalink Reply by Tim McMahan on February 7, 2010 at 5:58pm

Ok, I just talked to my flight buddy about this, and we may try some field tests next weekend. He had the great idea of simply hoisting an entire radio up the mast and locking it into trainer mode. Then I don't have to open up the Tx and try to run an antenna wire up to the antena. :)

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Permalink Reply by Morli on February 7, 2010 at 7:17pm

Make sure you anchor your tx real good, we have heard of runaway planes but never runway rc transmitters, imagine if it does so , what will you be chasing , your plane or your transmitter ?!! ? :-))))
good luck

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ModeratorPermalink Reply by Brian on February 7, 2010 at 11:51pm

When I first started in the military we had a backup emergency transmitter for CW. It had a wind up crank and a LONG wire which was lofted by a large box kite. A second operator would tap out a message using morse code. It was fun to practice with, but glad we didn't NEED to use it.

I thought about a communications relay teathered blimp for SAR along the same concept. Due to hills and obtructions on the ground a teathered balloon can go above and relay LOS signals from the dark side of an obstruction to others who otherwise would not recieve their call. I considered the same approach for RC and a video link back, but long distance video really comes back to just using the right antenna for the job.

A properly tuned patch antenna will increase your distance greatly and you don't need a bucket full of cement or large balloons...

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Permalink Reply by Robert Palmore on March 8, 2010 at 7:31pm

Joel,
I'm new to the civilian world of drones but have a good number of years experience in the Air Force plus had my ham radio license when I was 17 and have build an untold number of antenna one of which was used for remote controlling AQM 34 drone of Point Magoo Naval Air Station. With that background I still am not sure my idea is a good one due to the lower range of transmitter frequency. Lower the frequency the longer the antenna. Here is a link for making what is called a collinear antenna.
http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=15184
As you can see it rapidly becomes longer and longer. It is possible to stack several of these flattening the doughnut radiation pattern around your antenna flatter and flatter. What would be a more practical idea but still cumbersome at these frequencies is a yagi antenna.
http://www.skyscan.ca/Antennas.htm
You would have to tripod mount the antenna or have some one to hold the boom of the antenna so to point it at the plane.
Both of these ideas I don't think very well of but they are along the lines of your original quest. I wouldn't suggest the balloon or mast idea. The signal loss along your coax cable would surely consume any advantages you might gain. plus one really big reason not to go this rout is radio waves are line of sight and unless you intend to fly very low at these long ranges, you really don't gain any signal strength by just being higher.
Now that I've prattled on a bit and wasted every one's time here is what you really need if you want REAL RANGE.
http://www.webx.dk/rc/uhf-link3/uhf-link3.htm
This is the guy that really can speak from experience. I bow to his hands on experience and having actually produced exactly what your needing. Hope folks are ok with on the other junk.
Love and peace, Robert.

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