Good length for portable antenna

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Good length for portable antenna

Vic Rosenthal
I'm taking my K2/10 to a school on Wednesday to do a demonstration. I
have a 10m fiberglass pole, and my plan is to hook a wire to it and
either lean it against something or bungee-cord tie it to a bike rack or
whatever is there. I will deploy a counterpoise wire on the ground.
Given that it is the middle of the day, I will probably try 20 or 17m,
or maybe 15 if it sounds good.

My question is: what is a good length for the wire that will slope from
the pole to my K2, and what is a good length for the counterpoise? The
K2 has the internal tuner of course. The pole doesn't have to be fully
extended.

I intend to say "imagine that there is an earthquake and we are cut off,
phones don't work, etc. Watch how quickly I expand this pole and get on
the air (etc.)"
--
73,
Victor, 4X6GP
Rehovot, Israel
Formerly K2VCO
http://www.qsl.net/k2vco/
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Re: Good length for portable antenna

hb9brj
Check the colored table here.

For SOTA activations I'm using a KX3 and a 6m pole. Both antenna and counterpoise are 12.8m (42ft). Works fine on all bands between 60m and 6m. Not invented here, but copied from the "Bandspringer Midi" antenna offered by SOTAbeams.

73, Markus HB9BRJ
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Re: Good length for portable antenna

Vic Rosenthal
In reply to this post by Vic Rosenthal
I would like to thank all who responded on and off the list. What I will
do tomorrow is use a 5m radiator and a pair of 5m counterpoise wires,
for operation on 20 and 17m. That way I won't have to expand the pole
too much so it won't scare the teachers! For a permanent antenna that
will allow operation on more bands, I will use an 18.2m wire as the
radiator and several counterpoise wires of different lengths.

Yesterday I tested the short configuration on my roof, in a not-so-good
spot near the solar water heaters. I worked several Russian stations on
20, so I am set to go.

73,
Victor, 4X6GP
Rehovot, Israel
Formerly K2VCO
http://www.qsl.net/k2vco/

On 7 May 2017 10:24, Victor Rosenthal 4X6GP wrote:

> I'm taking my K2/10 to a school on Wednesday to do a demonstration. I
> have a 10m fiberglass pole, and my plan is to hook a wire to it and
> either lean it against something or bungee-cord tie it to a bike rack or
> whatever is there. I will deploy a counterpoise wire on the ground.
> Given that it is the middle of the day, I will probably try 20 or 17m,
> or maybe 15 if it sounds good.
>
> My question is: what is a good length for the wire that will slope from
> the pole to my K2, and what is a good length for the counterpoise? The
> K2 has the internal tuner of course. The pole doesn't have to be fully
> extended.
>
> I intend to say "imagine that there is an earthquake and we are cut off,
> phones don't work, etc. Watch how quickly I expand this pole and get on
> the air (etc.)"
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Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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Please help support this email list: http://www.qsl.net/donate.html
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