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Old May 21st 10, 05:29 PM posted to rec.radio.shortwave
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First recorded activity by RadioBanter: Jul 2006
Posts: 2,027
Default OK, so I'm gonna put up a new wire antenna...

On May 21, 5:48*am, Kevin Alfred Strom
wrote:
bpnjensen wrote:
On May 20, 10:32 am, bpnjensen wrote:
...and I'm gonna use existing trees to put it up about 30 feet above
ground, 15 feet above my rooftop on a 5x100 foot suburban lot. *Power
lines both in front and back of my house, the ones behind are much
higher voltage, but not real high-tension wires.


All other things being equal, am I better off:


1 - Putting this thing up parallel to, or more perpendicular to, the
powerlines?


2 - Having the coax meet the wire at the base of the tree and
grounding it there, or running the coax up the tree and then depending
on the outer braid on the coax for ground purposes? *The coax is
grounded at the first termination point at my MFJ antenna phasing unit
using a short, heavy copper wire to a ground rod.


Thanks,
Bruce


Gentlemen, Peter and Kevin, thank you for the excellent ideas - some I
knew, some ARE new - I don't have a lot of room to experiment, but my
trees are situated so as to allow a generally perpendicular
orientation to the power lines, my main nemesis. *Unfortunately, 30
feet is about as high as I can practically put them, but it's higher
than what I have now, so anything is an improvement, eh? *Again,
thanks :-)


You're welcome.

Scaling the inverted L I described to half size -- 30 feet vertical
and 45 feet horizontal -- will still give excellent performance.

73,

Kevin, WB4AIO.
--http://kevinalfredstrom.com/- Hide quoted text -

- Show quoted text -


Thanks! Mine is likely to be 30 feet vert and about 65 feet horz.

Bruce
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Old May 21st 10, 07:07 PM posted to rec.radio.shortwave
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First recorded activity by RadioBanter: May 2009
Posts: 544
Default OK, so I'm gonna put up a new wire antenna...

bpnjensen wrote:
On May 21, 5:48 am, Kevin Alfred Strom
wrote:
bpnjensen wrote:
On May 20, 10:32 am, bpnjensen wrote:
...and I'm gonna use existing trees to put it up about 30 feet above
ground, 15 feet above my rooftop on a 5x100 foot suburban lot. Power
lines both in front and back of my house, the ones behind are much
higher voltage, but not real high-tension wires.
All other things being equal, am I better off:
1 - Putting this thing up parallel to, or more perpendicular to, the
powerlines?
2 - Having the coax meet the wire at the base of the tree and
grounding it there, or running the coax up the tree and then depending
on the outer braid on the coax for ground purposes? The coax is
grounded at the first termination point at my MFJ antenna phasing unit
using a short, heavy copper wire to a ground rod.
Thanks,
Bruce
Gentlemen, Peter and Kevin, thank you for the excellent ideas - some I
knew, some ARE new - I don't have a lot of room to experiment, but my
trees are situated so as to allow a generally perpendicular
orientation to the power lines, my main nemesis. Unfortunately, 30
feet is about as high as I can practically put them, but it's higher
than what I have now, so anything is an improvement, eh? Again,
thanks :-)

You're welcome.

Scaling the inverted L I described to half size -- 30 feet vertical
and 45 feet horizontal -- will still give excellent performance.

73,

Kevin, WB4AIO.
--http://kevinalfredstrom.com/- Hide quoted text -

- Show quoted text -


Thanks! Mine is likely to be 30 feet vert and about 65 feet horz.

Bruce




That'll work well, too.

Putting a few radials on the ground (or, even better, elevated a few
feet above the ground) connected to the coaxial feedline's shield
will help the low angle (most distant) reception.

Recent studies indicate that radials don't need to be a quarter wave
long for best results as previously believed, either. About 195
divided by the frequency in MHz (with the answer in feet) is near
ideal, but they will still help at any length.

I've used flat rotor cable with the conductors pulled apart, or
separated strands of telephone PBX cable, stapled to the grassy yard
with staples made from cut up coat hangers bent into a U shape and
hammered over the wire every five or ten feet. If it's done
carefully, you can mow over them the same day without problems.
After a few weeks, the grass buries them and you can hardly tell the
wires are there.

If I was going to build a new inverted L today, I'd elevate the
feedpoint and radials about seven feet for higher efficiency -- but
it would look a bit more obtrusive.


Good luck with the antenna,


Kevin, WB4AIO.
--
http://kevinalfredstrom.com/
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Old May 21st 10, 07:20 PM posted to rec.radio.shortwave
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First recorded activity by RadioBanter: Jul 2006
Posts: 2,027
Default OK, so I'm gonna put up a new wire antenna...

On May 21, 11:07*am, Kevin Alfred Strom kevin.st...@revilo-
oliver.com wrote:
bpnjensen wrote:
On May 21, 5:48 am, Kevin Alfred Strom
wrote:
bpnjensen wrote:
On May 20, 10:32 am, bpnjensen wrote:
...and I'm gonna use existing trees to put it up about 30 feet above
ground, 15 feet above my rooftop on a 5x100 foot suburban lot. *Power
lines both in front and back of my house, the ones behind are much
higher voltage, but not real high-tension wires.
All other things being equal, am I better off:
1 - Putting this thing up parallel to, or more perpendicular to, the
powerlines?
2 - Having the coax meet the wire at the base of the tree and
grounding it there, or running the coax up the tree and then depending
on the outer braid on the coax for ground purposes? *The coax is
grounded at the first termination point at my MFJ antenna phasing unit
using a short, heavy copper wire to a ground rod.
Thanks,
Bruce
Gentlemen, Peter and Kevin, thank you for the excellent ideas - some I
knew, some ARE new - I don't have a lot of room to experiment, but my
trees are situated so as to allow a generally perpendicular
orientation to the power lines, my main nemesis. *Unfortunately, 30
feet is about as high as I can practically put them, but it's higher
than what I have now, so anything is an improvement, eh? *Again,
thanks :-)
You're welcome.


Scaling the inverted L I described to half size -- 30 feet vertical
and 45 feet horizontal -- will still give excellent performance.


73,


Kevin, WB4AIO.
--http://kevinalfredstrom.com/-Hide quoted text -


- Show quoted text -


Thanks! *Mine is likely to be 30 feet vert and about 65 feet horz.


Bruce


That'll work well, too.

Putting a few radials on the ground (or, even better, elevated a few
feet above the ground) connected to the coaxial feedline's shield
will help the low angle (most distant) reception.

Recent studies indicate that radials don't need to be a quarter wave
long for best results as previously believed, either. About 195
divided by the frequency in MHz (with the answer in feet) is near
ideal, but they will still help at any length.

I've used flat rotor cable with the conductors pulled apart, or
separated strands of telephone PBX cable, stapled to the grassy yard
with staples made from cut up coat hangers bent into a U shape and
hammered over the wire every five or ten feet. If it's done
carefully, you can mow over them the same day without problems.
After a few weeks, the grass buries them and you can hardly tell the
wires are there.

If I was going to build a new inverted L today, I'd elevate the
feedpoint and radials about seven feet for higher efficiency -- but
it would look a bit more obtrusive.

Good luck with the antenna,

Kevin, WB4AIO.
--http://kevinalfredstrom.com/- Hide quoted text -

- Show quoted text -


Thanks again - my space for radials is super limited - no more than
about 15 feet in any direction, and usually less - but maybe if there
are enough of them it would help make up for it.

I have a pretty good ground here - near the edge of SF Bay and only
about 10 feet above sea level, our ground water is pretty brackish and
seeps upward too. I don't know that this would help with the low-
angle reception, though. Maybe a ground rod plus attached radials?

Bruce
  #4   Report Post  
Old May 21st 10, 07:25 PM posted to rec.radio.shortwave
external usenet poster
 
First recorded activity by RadioBanter: May 2009
Posts: 544
Default OK, so I'm gonna put up a new wire antenna...

bpnjensen wrote:
On May 21, 11:07 am, Kevin Alfred Strom kevin.st...@revilo-
oliver.com wrote:
bpnjensen wrote:
On May 21, 5:48 am, Kevin Alfred Strom
wrote:
bpnjensen wrote:
On May 20, 10:32 am, bpnjensen wrote:
...and I'm gonna use existing trees to put it up about 30 feet above
ground, 15 feet above my rooftop on a 5x100 foot suburban lot. Power
lines both in front and back of my house, the ones behind are much
higher voltage, but not real high-tension wires.
All other things being equal, am I better off:
1 - Putting this thing up parallel to, or more perpendicular to, the
powerlines?
2 - Having the coax meet the wire at the base of the tree and
grounding it there, or running the coax up the tree and then depending
on the outer braid on the coax for ground purposes? The coax is
grounded at the first termination point at my MFJ antenna phasing unit
using a short, heavy copper wire to a ground rod.
Thanks,
Bruce
Gentlemen, Peter and Kevin, thank you for the excellent ideas - some I
knew, some ARE new - I don't have a lot of room to experiment, but my
trees are situated so as to allow a generally perpendicular
orientation to the power lines, my main nemesis. Unfortunately, 30
feet is about as high as I can practically put them, but it's higher
than what I have now, so anything is an improvement, eh? Again,
thanks :-)
You're welcome.
Scaling the inverted L I described to half size -- 30 feet vertical
and 45 feet horizontal -- will still give excellent performance.
73,
Kevin, WB4AIO.
--http://kevinalfredstrom.com/-Hide quoted text -
- Show quoted text -
Thanks! Mine is likely to be 30 feet vert and about 65 feet horz.
Bruce

That'll work well, too.

Putting a few radials on the ground (or, even better, elevated a few
feet above the ground) connected to the coaxial feedline's shield
will help the low angle (most distant) reception.

Recent studies indicate that radials don't need to be a quarter wave
long for best results as previously believed, either. About 195
divided by the frequency in MHz (with the answer in feet) is near
ideal, but they will still help at any length.

I've used flat rotor cable with the conductors pulled apart, or
separated strands of telephone PBX cable, stapled to the grassy yard
with staples made from cut up coat hangers bent into a U shape and
hammered over the wire every five or ten feet. If it's done
carefully, you can mow over them the same day without problems.
After a few weeks, the grass buries them and you can hardly tell the
wires are there.

If I was going to build a new inverted L today, I'd elevate the
feedpoint and radials about seven feet for higher efficiency -- but
it would look a bit more obtrusive.

Good luck with the antenna,

Kevin, WB4AIO.
--http://kevinalfredstrom.com/- Hide quoted text -

- Show quoted text -


Thanks again - my space for radials is super limited - no more than
about 15 feet in any direction, and usually less - but maybe if there
are enough of them it would help make up for it.

I have a pretty good ground here - near the edge of SF Bay and only
about 10 feet above sea level, our ground water is pretty brackish and
seeps upward too. I don't know that this would help with the low-
angle reception, though. Maybe a ground rod plus attached radials?

Bruce




That sounds good. The brackish water in the far field will
definitely help. The inverted L will work without the radials, just
not as well for the more distant stations.


All the best,



Kevin, WB4AIO.
--
http://kevinalfredstrom.com/
  #5   Report Post  
Old May 21st 10, 11:26 PM posted to rec.radio.shortwave
external usenet poster
 
First recorded activity by RadioBanter: Jul 2006
Posts: 2,027
Default OK, so I'm gonna put up a new wire antenna...

On May 21, 11:25*am, Kevin Alfred Strom kevin.st...@revilo-
oliver.com wrote:
bpnjensen wrote:
On May 21, 11:07 am, Kevin Alfred Strom kevin.st...@revilo-
oliver.com wrote:
bpnjensen wrote:
On May 21, 5:48 am, Kevin Alfred Strom
wrote:
bpnjensen wrote:
On May 20, 10:32 am, bpnjensen wrote:
...and I'm gonna use existing trees to put it up about 30 feet above
ground, 15 feet above my rooftop on a 5x100 foot suburban lot. *Power
lines both in front and back of my house, the ones behind are much
higher voltage, but not real high-tension wires.
All other things being equal, am I better off:
1 - Putting this thing up parallel to, or more perpendicular to, the
powerlines?
2 - Having the coax meet the wire at the base of the tree and
grounding it there, or running the coax up the tree and then depending
on the outer braid on the coax for ground purposes? *The coax is
grounded at the first termination point at my MFJ antenna phasing unit
using a short, heavy copper wire to a ground rod.
Thanks,
Bruce
Gentlemen, Peter and Kevin, thank you for the excellent ideas - some I
knew, some ARE new - I don't have a lot of room to experiment, but my
trees are situated so as to allow a generally perpendicular
orientation to the power lines, my main nemesis. *Unfortunately, 30
feet is about as high as I can practically put them, but it's higher
than what I have now, so anything is an improvement, eh? *Again,
thanks :-)
You're welcome.
Scaling the inverted L I described to half size -- 30 feet vertical
and 45 feet horizontal -- will still give excellent performance.
73,
Kevin, WB4AIO.
--http://kevinalfredstrom.com/-Hidequoted text -
- Show quoted text -
Thanks! *Mine is likely to be 30 feet vert and about 65 feet horz.
Bruce
That'll work well, too.


Putting a few radials on the ground (or, even better, elevated a few
feet above the ground) connected to the coaxial feedline's shield
will help the low angle (most distant) reception.


Recent studies indicate that radials don't need to be a quarter wave
long for best results as previously believed, either. About 195
divided by the frequency in MHz (with the answer in feet) is near
ideal, but they will still help at any length.


I've used flat rotor cable with the conductors pulled apart, or
separated strands of telephone PBX cable, stapled to the grassy yard
with staples made from cut up coat hangers bent into a U shape and
hammered over the wire every five or ten feet. If it's done
carefully, you can mow over them the same day without problems.
After a few weeks, the grass buries them and you can hardly tell the
wires are there.


If I was going to build a new inverted L today, I'd elevate the
feedpoint and radials about seven feet for higher efficiency -- but
it would look a bit more obtrusive.


Good luck with the antenna,


Kevin, WB4AIO.
--http://kevinalfredstrom.com/-Hide quoted text -


- Show quoted text -


Thanks again - my space for radials is super limited - no more than
about 15 feet in any direction, and usually less - but maybe if there
are enough of them it would help make up for it.


I have a pretty good ground here - near the edge of SF Bay and only
about 10 feet above sea level, our ground water is pretty brackish and
seeps upward too. *I don't know that this would help with the low-
angle reception, though. *Maybe a ground rod plus attached radials?


Bruce


That sounds good. The brackish water in the far field will
definitely help. The inverted L will work without the radials, just
not as well for the more distant stations.

All the best,

Kevin, WB4AIO.
--http://kevinalfredstrom.com/- Hide quoted text -

- Show quoted text -


Sounds like radials are the ticket - thanks!


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Old May 21st 10, 11:58 PM posted to rec.radio.shortwave
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First recorded activity by RadioBanter: Apr 2010
Posts: 12
Default OK, so I'm gonna put up a new wire antenna...

WB4AIO offers some excellent information and I would like to add the
following:

Generally speaking, (Note I stated GENERALLY SPEAKING here) end fed antennas
tend to be most directional in line with their longitudinal axis. In other
words, an inverted-L, end fed, would pick up the greatest
capture in the direction that it is "pointing."

Center fed antennas GENERALLY tend to be most directional perpendicular to
their
longitudinal axis.

Again, I stress these are VERY BROAD and GENERAL rules of thumb. Of course
there
are always exceptions such as the center fed Zepp which tends to be most
directive off its
ends. As one respondent stated...experiment. There is a reason they call
technical suppositions "theories."
It is because they are just that, theories only. Real world performance is
whatever you get and can be
morphed by ground conductivity, nearby structures, interactions and terrain
as well as theories that are conventional but one day will be refuted.

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Old May 22nd 10, 12:49 AM posted to rec.radio.shortwave
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First recorded activity by RadioBanter: Jul 2006
Posts: 2,027
Default OK, so I'm gonna put up a new wire antenna...

On May 21, 3:58*pm, "Clive" wrote:
WB4AIO offers some excellent information and I would like to add the
following:

Generally speaking, (Note I stated GENERALLY SPEAKING here) end fed antennas
tend to be most directional in line with their longitudinal axis. In other
words, an inverted-L, end fed, would pick up the greatest
capture in the direction that it is "pointing."

Center fed antennas GENERALLY tend to be most directional perpendicular to
their
longitudinal axis.

Again, I stress these are VERY BROAD and GENERAL rules of thumb. Of course
there
are always exceptions such as the center fed Zepp which tends to be most
directive off its
ends. As one respondent stated...experiment. There is a reason they call
technical suppositions "theories."
It is because they are just that, theories only. Real world performance is
whatever you get and can be
morphed by ground conductivity, nearby structures, interactions and terrain
as well as theories that are conventional but one day will be refuted.


Thanks, Clive - my room to experiment is extremely limited, but I will
do what I can.
  #8   Report Post  
Old May 22nd 10, 06:51 AM posted to rec.radio.shortwave
external usenet poster
 
First recorded activity by RadioBanter: Jun 2009
Posts: 635
Default OK, so I'm gonna put up a new wire antenna...

On May 21, 6:58*pm, "Clive" wrote:
WB4AIO offers some excellent information and I would like to add the
following:

Generally speaking, (Note I stated GENERALLY SPEAKING here) end fed antennas
tend to be most directional in line with their longitudinal axis. In other
words, an inverted-L, end fed, would pick up the greatest
capture in the direction that it is "pointing."

Center fed antennas GENERALLY tend to be most directional perpendicular to
their
longitudinal axis.

Again, I stress these are VERY BROAD and GENERAL rules of thumb. Of course
there
are always exceptions such as the center fed Zepp which tends to be most
directive off its
ends. As one respondent stated...experiment. There is a reason they call
technical suppositions "theories."
It is because they are just that, theories only. Real world performance is
whatever you get and can be
morphed by ground conductivity, nearby structures, interactions and terrain
as well as theories that are conventional but one day will be refuted.


I like that last sentence and believe it.
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