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Old September 26th 03, 07:57 AM
RHF
 
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Jason,

What you are talking about is not a true LongWire Antenna, but a most
likely a "Random" Wire Antenna.

The best advice about a Random Wire antenna is for what every
Horizontal Length that you can put up: Try to have it elevated
(height) at 1/3 that Length. The result will be an Omni-Directional
Antenna. That will allow you to receive signals from all directions.

Take the time to read about the Low Noise Antenna design by John Doty.
http://groups.yahoo.com/group/SWL-AM...enna/message/2

However, if you are talking about an Antenna . . .
- That is over 579 Foot Long . . .
- - The that is Truely a Different Question ? ? ?
- - - Sit Down and Have a Beverage or two ! ! !


iane ~ RHF
..
..
= = = =Jason
= = = wrote in message ...
Hello all

I live in Northern Alberta Canada, and I am going to put up a long wire
antenna. Should I orientate it in any specific direction, or just
string it up ?


Thanks, Jason


..
  #12   Report Post  
Old September 26th 03, 02:16 PM
Dale Parfitt
 
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Gregg wrote:

Behold, Dale Parfitt signalled from keyed 4-1000A filament:

Gregg wrote:

Unless the antenna is 1/2 wave above a prfectly conducting ground or
counterpoise, it really won't matter because it won't be directional.

Antenna theory, and NEC modeling radically disagree with this- How many

antennas do you want to see that are not 1/2 wave above a perfect ground
and yet show outstanding directionality?


W4OP

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Old September 26th 03, 05:40 PM
 
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In canada that will soon be against the law, one must over look
orientation because they were made that way.
  #14   Report Post  
Old September 26th 03, 06:28 PM
Michalkun
 
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Jason wrote in
:

Hello all

I live in Northern Alberta Canada, and I am going to put up a long wire
antenna. Should I orientate it in any specific direction, or just
string it up ?


Thanks, Jason



It depends what you what to listen too but I go with east-west orientation.
It works well.
  #15   Report Post  
Old September 26th 03, 07:32 PM
Gregg
 
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Behold, Dale Parfitt signalled from keyed 4-1000A filament:

Antenna theory, and NEC modeling radically disagree with this- How
many

antennas do you want to see that are not 1/2 wave above a perfect
ground and yet show outstanding directionality?


W4OP


Phased arrays can be made directional. We are talking longwires here.

--
Gregg
*It's probably useful, even if it can't be SPICE'd*
http://geek.scorpiorising.ca


  #16   Report Post  
Old September 26th 03, 10:32 PM
Dale Parfitt
 
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Gregg wrote:

Behold, Dale Parfitt signalled from keyed 4-1000A filament:

Antenna theory, and NEC modeling radically disagree with this- How
many
antennas do you want to see that are not 1/2 wave above a perfect
ground and yet show outstanding directionality?


W4OP


Phased arrays can be made directional. We are talking longwires here.


So am I. The higher a longwire antenna is in terms of wavelength, the
better defined the nulls become; i.e. its directional characteristics are
enhanced. Nothing magical about 1/2 wave above perfectly conducting
ground.
If you can read AO files, I'll be happy to send a file demonstrating this.

W4OP

  #17   Report Post  
Old September 27th 03, 01:24 AM
Gregg
 
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Behold, Dale Parfitt signalled from keyed 4-1000A filament:



Gregg wrote:

Behold, Dale Parfitt signalled from keyed 4-1000A filament:

Antenna theory, and NEC modeling radically disagree with this- How
many
antennas do you want to see that are not 1/2 wave above a perfect
ground and yet show outstanding directionality?

W4OP


Phased arrays can be made directional. We are talking longwires here.


So am I. The higher a longwire antenna is in terms of wavelength, the
better defined the nulls become; i.e. its directional characteristics
are enhanced. Nothing magical about 1/2 wave above perfectly conducting
ground.
If you can read AO files, I'll be happy to send a file demonstrating
this.

W4OP


Great! I learn something new every day :-)

AO file? I'm sure I can apt-get something to read them (I run Linux).
Fire away!

geek at scorpiorising dot ca

--
Gregg
*It's probably useful, even if it can't be SPICE'd*
http://geek.scorpiorising.ca
  #18   Report Post  
Old September 27th 03, 05:59 AM
Mark Keith
 
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Gregg wrote in message ...
Behold, Dale Parfitt signalled from keyed 4-1000A filament:

Antenna theory, and NEC modeling radically disagree with this- How
many
antennas do you want to see that are not 1/2 wave above a perfect
ground and yet show outstanding directionality?


W4OP


Phased arrays can be made directional. We are talking longwires here.


Not at 3 mhz. A 70 ft, or even a 100 ft wire is not even close to
qualifying as a longwire on 3mhz. It's just a random wire. Some of
the upper HF freq's, yes, it qualifies. On 3 mhz, it's not even a full
half wave. Worrying about the direction of the wire for 3 mhz use will
be a waste of time overall. It will be fairly omnidirectional and will
favor high angles. In fact, the maximum gain of such a wire on 3 mhz
will be straight up, unless he can get it real high up. You would have
to have the wire at least 120 ft in the air, to begin to lower the max
gain from 90 degrees overhead. The azumith pattern of the 100 ft wire
would be much like a normal dipole. A bit under 2 dbi gain in the
favored direction, and broadside to the wire like a dipole. Not a big
deal really. You will still hear plenty of signals off the ends. A
real longwire would show gain in line with the wire. "bidirectional".
Adding a terminating resister makes it fairly unidirectional. A
longwire must be at least 1 wave on the freq to be used. And thats a
real short longwire. Just barely is beginning to show gain off the
ends instead of broadside to the wire. Most are multi waves long on
the freq to be used. MK
  #19   Report Post  
Old September 27th 03, 05:37 PM
RHF
 
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jason, Jason. JASON !

So "Jason" just "How Long" will this Wire Antenna Be ? ? ?
- - - A true LongWire Antenna (multi-wavelength) ?
- - - Or simply a Random Wire Antenna to fit the avalable space ?
- - - What Shape or Type Wire Antenna ?

? Will this Wire Antenna be used for Transmitting and Receiving ?
- - - Any specific Frequency Band(s) for planned use ?

? Or, simply a "Receive ONLY" Wire Antenna for BCL and SWL ?
- - - For Broadbanded use from 500 kHz to 30 MHz ?


iane ~ RHF
..
..
= = = (RHF)
= = = wrote in message om...
Jason,

What you are talking about is not a true LongWire Antenna, but a most
likely a "Random" Wire Antenna.

The best advice about a Random Wire antenna is for what every
Horizontal Length that you can put up: Try to have it elevated
(height) at 1/3 that Length. The result will be an Omni-Directional
Antenna. That will allow you to receive signals from all directions.

Take the time to read about the Low Noise Antenna design by John Doty.
http://groups.yahoo.com/group/SWL-AM...enna/message/2

However, if you are talking about an Antenna . . .
- That is over 579 Foot Long . . .
- - The that is Truely a Different Question ? ? ?
- - - Sit Down and Have a Beverage or two ! ! !


iane ~ RHF
.
.
= = = =Jason
= = = wrote in message ...
Hello all

I live in Northern Alberta Canada, and I am going to put up a long wire
antenna. Should I orientate it in any specific direction, or just
string it up ?


Thanks, Jason


.

  #20   Report Post  
Old September 27th 03, 07:22 PM
Dale Parfitt
 
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Gregg wrote:

Behold, Dale Parfitt signalled from keyed 4-1000A filament:

Gregg wrote:

Behold, Dale Parfitt signalled from keyed 4-1000A filament:

Antenna theory, and NEC modeling radically disagree with this- How
many
antennas do you want to see that are not 1/2 wave above a perfect
ground and yet show outstanding directionality?

W4OP

Phased arrays can be made directional. We are talking longwires here.


So am I. The higher a longwire antenna is in terms of wavelength, the
better defined the nulls become; i.e. its directional characteristics
are enhanced. Nothing magical about 1/2 wave above perfectly conducting
ground.
If you can read AO files, I'll be happy to send a file demonstrating
this.

W4OP


Great! I learn something new every day :-)

AO file? I'm sure I can apt-get something to read them (I run Linux).
Fire away!

geek at scorpiorising dot ca


Hi Gregg,
You will need any version of Antenna Optimizer. Alternatively, I can probably
generate an EZNEC file- a demo version of which can be downloaded from the
EZNEC site.

Dale W4OP

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