Kite antenna with ocean ground -- charge buildup?
 

I will be running 28 ga. magnet wire along (& around) a 350 ft. kite
line tied to a windborne kite -- for 160M work.

The other leg will be bare copper wire that runs 50 ft to the ocean.

I am not sure if this is a longwire antenna with counterpoise or a
tilted vertical with ground plane.

Anyhow, I have been told that the wind will cause static charge to
build on the magnet wire and that a path to ground must be provided.

1) Is this true?

2) If it is true, would the problem be solved with, say, a 1,000 ohm
resistor between the longwire and and sal****er ground leads at my
tuner?

Ken KC2JDY




Ken
(to reply via email
remove "zz" from address)

Ken wrote:

I will be running 28 ga. magnet wire along (& around) a 350 ft. kite
line tied to a windborne kite -- for 160M work.

The other leg will be bare copper wire that runs 50 ft to the ocean.

I am not sure if this is a longwire antenna with counterpoise or a
tilted vertical with ground plane.

Anyhow, I have been told that the wind will cause static charge to
build on the magnet wire and that a path to ground must be provided.

1) Is this true?

2) If it is true, would the problem be solved with, say, a 1,000 ohm
resistor between the longwire and and sal****er ground leads at my
tuner?

Ken: In answer to 1 Yes. It will happen and there is nothing that can be
done about stopping it.

In answer to 2, that would work as one way to make the charge bleed to
ground. Another way to bleed the charge off to ground is to put a high
value inductor between the two wires. At RF frequencies it will like as
a high impedance. At DC it is almost a dead short.

Personally I think the inductor would be the better choice.

Al Butler ka0ies

Ken

Check out this very useful site:

http://www.qsl.net/g4vgo/





"Ken" wrote in message
...
I will be running 28 ga. magnet wire along (& around) a 350 ft. kite
line tied to a windborne kite -- for 160M work.

The other leg will be bare copper wire that runs 50 ft to the ocean.

I am not sure if this is a longwire antenna with counterpoise or a
tilted vertical with ground plane.

Anyhow, I have been told that the wind will cause static charge to
build on the magnet wire and that a path to ground must be provided.

1) Is this true?

2) If it is true, would the problem be solved with, say, a 1,000 ohm
resistor between the longwire and and sal****er ground leads at my
tuner?

Ken KC2JDY




Ken
(to reply via email
remove "zz" from address)

Ken wrote:
"I have been told that wind will cause static charge to build on the
magnet wire and that a path to ground must be provided."

I`ve seen wind sweeping broadcast tower guy wires charge them until they
flashed across their insulators again and again. That means the guy wire
insulators were very good. a very small leakage is usually sufficient to
discharge a conductor, but the guy wire is broken in several places with
insulators. The voltage between segments was in kilovolts to produce
corona and flashover. A resistance so low as 1000 ohms is usually much
lower than required to drain charge.

An ungriunded conductor in air will accumulate charge from rain drops,
snow flakes, dust particles, and charged air which strikes it.

Static drain can be accomplished by a connection to ground through a
choke or transformer coil. A resistor so high in value as to not affect
operation of the "magnet wire" also is effective. Operation may be
compared with the grid resistor in a vacuum tube circuit which leaks the
charge from a grid. In the case of an elevated conductor, megohms of
resistance may be low enough to drain the charge, depending upon the
charge accumulation rate and the kilovolts required to produce corona
and flashover at some sharp projection on the charged surface.

Best regards, Richard Harrison, KB5WZI

On Tue, 02 Dec 2003 02:06:37 GMT, Ken wrote:

I will be running 28 ga. magnet wire along (& around) a 350 ft. kite
line tied to a windborne kite -- for 160M work.

The other leg will be bare copper wire that runs 50 ft to the ocean.

In case nobody's told you prior to this, don't use the wire alone to
connect to the kite. Use conventional kite line (I use 100# test
dacron) and support your antenna on the kite line.

Make sure your ground wire is plentiful and of a decently large gauge,
just as you'd use at home. Sea water is a good conductor, but you
still need surface area. If you're on board a ship, you're probably
better off attaching to the ship's ground. However, every situation
is different...

I am not sure if this is a longwire antenna with counterpoise or a
tilted vertical with ground plane.

Depends on how high an angle your kite flies :-) I have used a
Stratoscoop III, a Jalbert Parafoil, and various box and delta kites.
Of these, the Stratoscoop III is definitely the highest angle flier,
but it's not a stable kite at those angles. The box kites and Delta
kites proved most reliable, and the Parafoil pulled the hardest,
though it flew at relatively low angles. I should have tinkered with
the Parafoil, but I had other kites at the time, so I chose to use
them instead.

Anyhow, I have been told that the wind will cause static charge to
build on the magnet wire and that a path to ground must be provided.

1) Is this true?

YES. BEEN THERE, LEARNED IT THE HARD WAY. DON'T REPEAT MY MISTAKE.

2) If it is true, would the problem be solved with, say, a 1,000 ohm
resistor between the longwire and and sal****er ground leads at my
tuner?

I used a 100 k Ohm resistor. The value can be pretty high as there is
very little current. Later I used an RF choke with equal protection
and equal success.

73, and have fun!


Jake Brodsky, AB3A
"Beware of the massive impossible!"