Delta Loops
 

Hi all:

I've been thinking about making a vertically polarized Delta Loop for 40m.
I've seen articles on the internet having the feed point at one of the lower
corners of the triangle for vertical polorization, others having the feed point
on one of the sides, 1/4 wl from the top. Does it make any difference if its
sloping (within reason) or does it need to be perpendicular to the ground?

Anyone here have any experience here?


Thanks,

Bob--KD8WU

U of M
GO BLUE!!

GOD, GUNS, and GUTS
PROTECT AMERICA

On 28 Feb 2004 21:42:38 GMT, am (Bob Colenso)
wrote:

Hi all:

I've been thinking about making a vertically polarized Delta Loop for 40m.
I've seen articles on the internet having the feed point at one of the lower
corners of the triangle for vertical polorization, others having the feed point
on one of the sides, 1/4 wl from the top. Does it make any difference if its
sloping (within reason) or does it need to be perpendicular to the ground?

Anyone here have any experience here?


Thanks,

Bob--KD8WU

U of M
GO BLUE!!

GOD, GUNS, and GUTS
PROTECT AMERICA


Good Morning Bob,

I've found here that sloping is ok within reason. The feed point
should be at the 1/4 wave down from the apex , I've tried both and it
seem to work better for me there. you might want to take a look a
Cebik's site at

http://www.cebik.com/scv2.html

I would not that if you are planning on using this loop on any band
other than 40m buy tuning it with a tuner. You would be better off
mounting it in the Horizontal plan..

73 Dave kc1di

Dave, KC1DI wrote:
"You would be better off mounting it in the Horizontal plan(e)...(at
other than 40 m)

Performance versus polarization depends on soil loss in the antenna
area.

Over poor earth, horizontal polarization is better for take-off angles
above 35 degrees. Below 35 degrees, vertical polarization is a little
better, but not much, maybe 2dB.

Over good earth, vertical antennas work much better than they do over
poor earth. For take-off angles below 30 degrees, the large loop in the
vertical plane may be 10 dB better than a large horizontal loop.

Antenna height tends to lower take-off angle.

If you want expert testimony, see "ON4UN`s "Low-Band DXing" page 10-9.
ARRL is the publisher.

Best regards, Richard Harrison, KB5WZI

I have had good luck with the superloop 40 from radioworks which is a
bottom fed vertical delta loop. Contrary to Cebik, I find that it's
about 1/2 S unit better on 40M than my dipole, although the vertical
section is a stub and makes it not exactly a delta loop on 40M..
fyi
JR AA2T

On 28 Feb 2004 21:42:38 GMT, am (Bob Colenso)
wrote:

Hi all:

I've been thinking about making a vertically polarized Delta Loop for 40m.
I've seen articles on the internet having the feed point at one of the lower
corners of the triangle for vertical polorization, others having the feed point
on one of the sides, 1/4 wl from the top. Does it make any difference if its
sloping (within reason) or does it need to be perpendicular to the ground?

Anyone here have any experience here?


Thanks,

Bob--KD8WU

U of M
GO BLUE!!

GOD, GUNS, and GUTS
PROTECT AMERICA

On Mon, 1 Mar 2004 11:56:38 -0600 (CST),
(Richard Harrison) wrote:

Dave, KC1DI wrote:
"You would be better off mounting it in the Horizontal plan(e)...(at
other than 40 m)

Performance versus polarization depends on soil loss in the antenna
area.

Over poor earth, horizontal polarization is better for take-off angles
above 35 degrees. Below 35 degrees, vertical polarization is a little
better, but not much, maybe 2dB.

Over good earth, vertical antennas work much better than they do over
poor earth. For take-off angles below 30 degrees, the large loop in the
vertical plane may be 10 dB better than a large horizontal loop.

Antenna height tends to lower take-off angle.

If you want expert testimony, see "ON4UN`s "Low-Band DXing" page 10-9.
ARRL is the publisher.

Best regards, Richard Harrison, KB5WZI

Hi Richard,

I agree with what you've said but I think you missed my point.. above
the fundamental frequency a loop is better in the horizontal plane,, a
vertical plan loop that is 2 wavelength or more tends to become more
and more of a high angle radiator as you move up in frequency.

what you have stated above is correct for a 1 wave horizontal loop in
that case i would agree that a vertical loop would be perfered.

in any event try them both and make your own conclusions.

73 Dave kc1di

Bob, KD8WU wrote:
"I`ve had good luck with the superloop 40 from radioworks which is a
bottom fed vertical delta loop."

I`m ignorant of the superloop 40 but am guessing it is a small multiturn
loop for enhancing reception only. If so, the following applies. If the
superloop 40 is a full wavelength in circumference, I`m all wet.

"Delta loop" usually implies more than a triangular shape. It usually
means a large loop, often an entire wavelength in circumference.

When the circumference of a loop is a small fraction of a wavelength,
current throughout a turn in the loop is nearly in the same phase and
magnitude. This is responsible for a null in the loop`s response
perpendicular to the plane of the loop. Loop response is in all the
directions which are in the plane of the loop.

Not so with the large loop, delta, quad, or circular. These large loops
have a response perpendicular to the plane of the loop which allows loop
elements to be stacked like the rods in a Yagi so that a cmbination
called a "Quagi" can be built.

A small loop with one or 40 turns is a different animal from a large
loop.

Best regards, Richard Harrison, KB5WZI

All the theory is fine, but the bottom line on the superloop 80 or 40 in the
vertical plan is that they work and very well at that. Larry
"Richard Harrison" wrote in message
...
Bob, KD8WU wrote:
"I`ve had good luck with the superloop 40 from radioworks which is a
bottom fed vertical delta loop."

I`m ignorant of the superloop 40 but am guessing it is a small multiturn
loop for enhancing reception only. If so, the following applies. If the
superloop 40 is a full wavelength in circumference, I`m all wet.

"Delta loop" usually implies more than a triangular shape. It usually
means a large loop, often an entire wavelength in circumference.

When the circumference of a loop is a small fraction of a wavelength,
current throughout a turn in the loop is nearly in the same phase and
magnitude. This is responsible for a null in the loop`s response
perpendicular to the plane of the loop. Loop response is in all the
directions which are in the plane of the loop.

Not so with the large loop, delta, quad, or circular. These large loops
have a response perpendicular to the plane of the loop which allows loop
elements to be stacked like the rods in a Yagi so that a cmbination
called a "Quagi" can be built.

A small loop with one or 40 turns is a different animal from a large
loop.

Best regards, Richard Harrison, KB5WZI

On Mon, 1 Mar 2004 22:29:36 -0600 (CST),
(Richard Harrison) wrote:

Bob, KD8WU wrote:
"I`ve had good luck with the superloop 40 from radioworks which is a
bottom fed vertical delta loop."

I`m ignorant of the superloop 40 but am guessing it is a small multiturn
loop for enhancing reception only. If so, the following applies. If the
superloop 40 is a full wavelength in circumference, I`m all wet.

"Delta loop" usually implies more than a triangular shape. It usually
means a large loop, often an entire wavelength in circumference.

When the circumference of a loop is a small fraction of a wavelength,
current throughout a turn in the loop is nearly in the same phase and
magnitude. This is responsible for a null in the loop`s response
perpendicular to the plane of the loop. Loop response is in all the
directions which are in the plane of the loop.

Not so with the large loop, delta, quad, or circular. These large loops
have a response perpendicular to the plane of the loop which allows loop
elements to be stacked like the rods in a Yagi so that a cmbination
called a "Quagi" can be built.

A small loop with one or 40 turns is a different animal from a large
loop.

Best regards, Richard Harrison, KB5WZI


Richard the Super loop is a full wave loop on the lowest operating
frequency .. IE Super loop 40 is a full wave 40 Meter delta loop.. the
difference is that it has a shorted stup opposet the fedpoint which
present a high impedence on twice the fundamental frequecy which
effectively opens the loop on bands above the fundamental so that it
acts more like a Bi-Square antenna on twice the frequency of design.

73 Dave KC1DI

KC1DI wrote:
Richard the Super loop is a full wave loop on the lowest operating
frequency .. IE Super loop 40 is a full wave 40 Meter delta loop.. the
difference is that it has a shorted stup opposet the fedpoint which
present a high impedence on twice the fundamental frequecy which
effectively opens the loop on bands above the fundamental so that it
acts more like a Bi-Square antenna on twice the frequency of design.

Dave, please turn on your spell checker.
Does "stup opposet" mean "stub opposite"?
--
73, Cecil http://www.qsl.net/w5dxp



-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

On Tue, 02 Mar 2004 13:59:29 -0600, Cecil Moore
wrote:

KC1DI wrote:
Richard the Super loop is a full wave loop on the lowest operating
frequency .. IE Super loop 40 is a full wave 40 Meter delta loop.. the
difference is that it has a shorted stup opposet the fedpoint which
present a high impedence on twice the fundamental frequecy which
effectively opens the loop on bands above the fundamental so that it
acts more like a Bi-Square antenna on twice the frequency of design.

Dave, please turn on your spell checker.
Does "stup opposet" mean "stub opposite"?

Thanks Cecil it does me stub ! not Stup Sorry.
73 Dave ...