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Old April 9th 06, 10:49 PM posted to rec.radio.amateur.antenna
Harbin
 
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Default Counterpoise wire length

Counterpoise wire length. I've heard that it should be 1/4 wave, and then again I've
heard it should be 1/2. Which is correct, or will they both work?

--
SeeYaa Harbin Osteen KG6URO

This is YOUR futu
http://halturnershow.com/aztlan_caps.wmv

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Old April 9th 06, 11:53 PM posted to rec.radio.amateur.antenna
Yuri Blanarovich
 
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Default Counterpoise wire length

Counterpoise to what?

You need to describe what are you trying "counterpoison".

Yuri, K3BU

"Harbin" wrote in message
...
Counterpoise wire length. I've heard that it should be 1/4 wave, and then
again I've
heard it should be 1/2. Which is correct, or will they both work?

--
SeeYaa Harbin Osteen KG6URO

This is YOUR futu
http://halturnershow.com/aztlan_caps.wmv

-



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Old April 10th 06, 06:53 AM posted to rec.radio.amateur.antenna
 
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Default Counterpoise wire length


Harbin wrote:
Counterpoise wire length. I've heard that it should be 1/4 wave, and then again I've
heard it should be 1/2. Which is correct, or will they both work?


The lowest impedance presented by a single counterpoise wire is when
the counterpoise is resonant and 1/4 wl long electrically.

When a single counterpoise wire is near 1/2 wl long and resonant, it
has a very high end impedance.

If the counterpoise is under a dipole or some other antenna just to
isolate it from ground losses, a 1/2 wl long counterpoise or longer is
best.

If the counterpoise is used as a termination to allow forceing current
into a Marconi antenna or an end-fed antenna, or used to provide a
ground path for unwanted currents, it is best if it is 1/4 wl long.

More counterpoise wires are always better, because the more you use the
less critical length is and the lower loss is. There is of course a
point where more won't help. With 1/4 wl wires, 50 or so placed
radially are near perfect. Adding more won't make a noticeable
difference. Once the counterpoise wires are .025 to .05 wavelengths
apart at the widest points, adding more will generally not help.

I use 100 200 foot long wires on one of my 160 meter verticals. On my
other verticals I have 1/4 wl radials, and once I reached 40-50 radials
adding more made no measureable difference at all.

73 Tom

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Old April 11th 06, 09:19 AM posted to rec.radio.amateur.antenna
Harbin
 
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Default Counterpoise wire length

Say I was using a short wave receiver, and I'm on the second floor, without a good
ground. I would be running a long wire. Would it help to cut a counterpoise for the
bands I wish to listen to, a single wire for each band? Would it be 1/4, or 1/2 wave?

--
SeeYaa Harbin Osteen KG6URO

This is YOUR futu
http://halturnershow.com/aztlan_caps.wmv

-
"Yuri Blanarovich" wrote in message news
Counterpoise to what?

You need to describe what are you trying "counterpoison".

Yuri, K3BU



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Old April 11th 06, 09:23 AM posted to rec.radio.amateur.antenna
Harbin
 
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Default Counterpoise wire length

Looks like I'm looking for a 1/4 wave. Thanks

--
SeeYaa Harbin Osteen KG6URO

This is YOUR futu
http://halturnershow.com/aztlan_caps.wmv

-
wrote in message ps.com...

Harbin wrote:
Counterpoise wire length. I've heard that it should be 1/4 wave, and then again I've
heard it should be 1/2. Which is correct, or will they both work?


The lowest impedance presented by a single counterpoise wire is when
the counterpoise is resonant and 1/4 wl long electrically.

When a single counterpoise wire is near 1/2 wl long and resonant, it
has a very high end impedance.

If the counterpoise is under a dipole or some other antenna just to
isolate it from ground losses, a 1/2 wl long counterpoise or longer is
best.

If the counterpoise is used as a termination to allow forceing current
into a Marconi antenna or an end-fed antenna, or used to provide a
ground path for unwanted currents, it is best if it is 1/4 wl long.

More counterpoise wires are always better, because the more you use the
less critical length is and the lower loss is. There is of course a
point where more won't help. With 1/4 wl wires, 50 or so placed
radially are near perfect. Adding more won't make a noticeable
difference. Once the counterpoise wires are .025 to .05 wavelengths
apart at the widest points, adding more will generally not help.

I use 100 200 foot long wires on one of my 160 meter verticals. On my
other verticals I have 1/4 wl radials, and once I reached 40-50 radials
adding more made no measureable difference at all.

73 Tom





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Old April 11th 06, 04:41 PM posted to rec.radio.amateur.antenna
Yuri Blanarovich
 
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Default Counterpoise wire length

If you are using long wire for different bands, you can tap to your water
pipe for ground, or metal frame of the screen door, or most likely your RX
is already "grounded" through its AC PS. You can try through capacitor of
about 10000 uuF/1kV from your RX ground to your ground pin the AC outlet.
Alternative I used for antenna when in restricted area, just run wire from
ant terminal on RX through capacitor of about 10 k rated at least at 3000V
to one of the connections in AC outlet, well insulated and mounted in AC
plug.

Yuri, K3BU


"Harbin" wrote in message
...
Say I was using a short wave receiver, and I'm on the second floor,
without a good
ground. I would be running a long wire. Would it help to cut a
counterpoise for the
bands I wish to listen to, a single wire for each band? Would it be 1/4,
or 1/2 wave?

--
SeeYaa Harbin Osteen KG6URO



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