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Amateur Radio Balloon-lifted Antenna Resources:
My latest article -- "The Quick & Easy “Balloon-assisted” Low
Band Loop Antenna":

Look for my latest article -- "The Quick & Easy “Balloon-assisted” Low Band Loop Antenna" -- in the January 2009
QST!  Here is additional information about materials used to construct this antenna:
An 80-meter loop is going up at the West Valley
Amateur Radio Association / ESL Amateur Radio
Club 2007 Field Day.
balloons
 I use latex or chloroprene “car dealer” balloons from my local helium source or the web (e.g.
www.balloonlovers.com, also try eBay.)  40” balloons ~$3., 5.5’ balloons are ~$18.  Store
balloons in a cool, dark place.

Harry, W4HFP, advises that www.balloons.com offer a variety of high quality balloons in sizes
from 5 inches to 8 feet in diameter.
heavy antenna
wire
 Any typical 14 or 16 gauge stranded antenna wire will do.  Cost ~$15.00.
helium
 Helium can be purchased, from local party balloon suppliers (I have been using www.
peoplegreeters.com for many years), industrial gas, or welding supply shops.  Most recently I
paid ~$0.55/cubic foot (June 2008).  A 4’ balloon needs ~34 cubic feet, and a 5’ balloon needs
~65 cubic feet.  Remember that balloons pop, so have extra helium and balloons on hand!
insulators
 Any conventional antenna insulator will do.  Cost: ~$1.00 each.
light antenna wire        I use surplus stranded 22-gauge wire from Fair Radio Sales.  Part
number SEB-400X3. http://www.fairradio.com/catalog.php?mode=viewitem&item=1221, 306’
spool  for $14.95.
rope
 For spreading the lower section, I like using light and strong parachute cord available in surplus
stores.  Cost: ~7cents/foot.
static bleed-off
resistors
 In high static areas, some have reported needing to use static bleed-off resistors between the
ladder line conductors coming in to the tuner, and ground.  Differential-mode buildup will not
occur for this antenna design since loops present a short at DC, but common mode build-up is
possible.  We have never experienced this problem at our QTH, however, perhaps because of
this advantage or perhaps because of our dryer climate in California.  But I have read reports
from other balloon antenna enthusiasts that static build-up can be an issue for very large
monopole antennas.
If static buildup is an issue for you, connect two resistors between the two conductors of the
ladder line and ground.  1MΩ or more, non-inductive power resistors rated for over 2 watts
should do for up to 100 Watts radiated power (i.e. Digikey PPC1.0MW-3JCT-ND).
terminal blocks
 I cut individual sections from double-row, screw-type terminal blocks (e.g. Jameco P/Ns 215011
or 215029) to use for wire splices.   Cost: ~$2.
tether line &
swivels
 80-pound-test multifilament fishing line and swivels can be found in any fishing store.  Cost is a
few dollars.
tuners
 Use only a tuner made for balanced lines!  Others do not work!  The MFJ-974HB (~$200.)
www.mfjenterprises.com  and old Johnson Matchbox tuners work well.
Click here for an Excel spreadsheet which calculates the dimensions of this antenna for different design frequencies.

Important Balloon-lifted Safety Tips:

  • Always comply with appropriate government regulations (see the link to US FAA regulations below).

  • Make sure you have plenty of space!  Never fly a balloon antenna where it could possibly come down on a
    power line, any other wire, any structure, roads, or rail lines.

  • Fly balloon antennas only in light to moderate winds.  Pull the antenna down when winds rise, and wait for
    the winds to subside.

  • Use tether lines sizes appropriate for the possible wind load.  Do not used frayed or damaged tether lines.

  • Wear gloves when handling tethers or antenna wire.

  • Never fly a balloon antenna in a thunder storm.

  • Inflate with Helium only.

  • Always tether the balloon to the ground with a line separate from the antenna support structure.  Tether lines
    should be stronger than balloons.  Use good knots like the bowline.

  • Be careful with helium tanks.  When transporting, secure tanks so that they can not role around in a vehicle.  
    Tanks are heavy, so always have enough people around when lifting.  Always keep the valve closed and the
    nozzle cover secured when not actually inflating balloons.  Never let tanks fall – particularly when the nozzle is
    exposed – as a leak in the nozzle can turn a tank in to a missile.

  • Secure tether lines to solid objects on the ground.  Tie colorful flag tape to the lines so that pedestrians and
    cars see them and do not become entangled.


Helpful Balloon-lifted Antenna Links: