Discussion:
Why does the Lazy H antenna suck in the real world on 11 meters?
(too old to reply)
Michael
2008-07-05 16:42:20 UTC
Permalink
I've seen the Lazy H mentioned in many antenna books over the years,
so I decided to try one on 10 meters. According to the ARRL handbook
the Lazy H is two collinear elements stacked on above the other, Each
collinear element is made up of two 1/2 wave elements. I chose to
use 5/8 wave spacing between the top and bottom elements. I connected
the top and bottom elements with 450 ohm 16 gauge stranded ladder line
(window line). After building the antenna I verified connectivity
between the top and bottom right elements and the top and bottom left
elements. I color coded the end insulators on each side so I could
easily see which top and bottom elements were connected to each other.
The antenna book says to connect the 450 ohm ladder line from the
antenna tuner to the middle of the 450 ladder line that connects top
and bottom elements. Ok done. Now I put up the antenna and make sure
the top and bottom elements are in phase. That is both left connected
elements are on the left and both right connected element are on the
right. I also make sure there is no twist in the ladder line
connecting the top and bottom elements. I also checked the other
ends of the 450 ohm ladder line feeding the antenna has connectivity
at the antenna, and the left and right sides of the ladder line do not
have connectivity. The 450 ohm ladder line feeding the antenna is
about 200 feet long.
Now I bring the 450 ohm feedline in to the house, hook it to my
Dentron MT-2000 antenna tuner with the 4:1 balun inside, tune it up,
and it sucks! Both my half wave horizontal dipole and my Solarcon
Max-2000 blow it away on incoming skip even in the preferred direction
of the lazy H. I rechecked my connections and the lengths of the
elements and spacing and they are correct. I did take in to account
the velocity factor of the 450 ladder line that connects the top
elements to the bottom elements. The antenna book says the length of
the 450 ladder lien between the antenna and the antenna tuner can e
any lenght.
The bottom element is at least 1/2 wave of the ground, and the top
element is 5/8ths wave above that. What did I do wrong?

Michael
n***@wt.net
2008-07-05 17:16:21 UTC
Permalink
Post by Michael
I also make sure there is no twist in the ladder line
connecting the top and bottom elements.
I'd have to look at a diagram of the lazy H, but I think that
is your problem. The elements need to be transposed.
Which means you want a 1/2 twist in the connecting
ladder line. IE: the bottom left should connect to the
top right, and visa versa.
John Smith
2008-07-05 17:33:52 UTC
Permalink
Post by n***@wt.net
Post by Michael
I also make sure there is no twist in the ladder line
connecting the top and bottom elements.
I'd have to look at a diagram of the lazy H, but I think that
is your problem. The elements need to be transposed.
Which means you want a 1/2 twist in the connecting
ladder line. IE: the bottom left should connect to the
top right, and visa versa.
Just quickly:

http://www.amwindow.org/tech/htm/tenmant/tenmant.htm
http://www.amwindow.org/tech/htm/tenmant/fig5.htm

http://www.kw2hv.com/lazy_h.html

http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=14923

Regards,
JS
Michael
2008-07-05 18:15:05 UTC
Permalink
Post by n***@wt.net
Post by Michael
I also make sure there is no twist in the ladder line
connecting the top and bottom elements.
I'd have to look at a diagram of the lazy H, but I think that
is your problem. The elements need to be transposed.
Which means you want a 1/2 twist in the connecting
ladder line. IE: the bottom left should connect to the
top right, and visa versa.
As I understand it you only twist the interconnecting ladder line if
you are feeding the Lazy H antenna at the bottom (end fire), but if
you are feeding it in the middle of the interconnecting 450 ladder
line then you leave out the twist. At least that's what I'm gathering
from the pictures I have found.

One correction. I have a Dentron MT-3000a antenna tuners with a 4:1
balun and not the MT-2000.
Wimpie
2008-07-05 19:55:31 UTC
Permalink
Post by Michael
I've seen the Lazy H mentioned in many antenna books over the years,
so I decided to try one on 10 meters. According to the ARRL handbook
the Lazy H is two collinear elements stacked on above the other, Each
collinear element is made up of two 1/2 wave elements. I chose to
use 5/8 wave spacing between the top and bottom elements. I connected
the top and bottom elements with 450 ohm 16 gauge stranded ladder line
(window line). After building the antenna I verified connectivity
between the top and bottom right elements and the top and bottom left
elements. I color coded the end insulators on each side so I could
easily see which top and bottom elements were connected to each other.
The antenna book says to connect the 450 ohm ladder line from the
antenna tuner to the middle of the 450 ladder line that connects top
and bottom elements. Ok done. Now I put up the antenna and make sure
the top and bottom elements are in phase. That is both left connected
elements are on the left and both right connected element are on the
right. I also make sure there is no twist in the ladder line
connecting the top and bottom elements. I also checked the other
ends of the 450 ohm ladder line feeding the antenna has connectivity
at the antenna, and the left and right sides of the ladder line do not
have connectivity. The 450 ohm ladder line feeding the antenna is
about 200 feet long.
Now I bring the 450 ohm feedline in to the house, hook it to my
Dentron MT-2000 antenna tuner with the 4:1 balun inside, tune it up,
and it sucks! Both my half wave horizontal dipole and my Solarcon
Max-2000 blow it away on incoming skip even in the preferred direction
of the lazy H. I rechecked my connections and the lengths of the
elements and spacing and they are correct. I did take in to account
the velocity factor of the 450 ladder line that connects the top
elements to the bottom elements. The antenna book says the length of
the 450 ladder lien between the antenna and the antenna tuner can e
any lenght.
The bottom element is at least 1/2 wave of the ground, and the top
element is 5/8ths wave above that. What did I do wrong?
Michael
Hi Michael,

Normally spoken the feedline between top to bottom elements is
0.5lambda long, without twist, feeding in the middle. The path from
feedpoint to end of the radiation elements is 0.75 lambda, giving an
almost real low input impedance (on order of 30 Ohms, depending on
thickness of radiating elements). In fact you have two full wave
dipoles fed in phase that give most radiation (ground ignored)
perpendicular to the array (bidirectional). There is a vertical null

Why choosing 5/8 lambda vertical element spacing? You create a
vertical lobe and a null in the elevation radiation pattern under
about 53 degrees. You also get a strong reactive input impedance, but
this may not be a problem with the ladder line.

Did you do some indicative field strength measurements (diode
detector) to find out whether it (and the elements) do(es) radiate
(comparing to the other antennas)? It may also reveal some hidden
things.

Maybe somebody knows a loss figure for your ladder line (at 28 MHz) to
assess the losses in the line (200ft part) because of bad VSWR.

Best regards,

Wim
PA3DJS
www.tetech.nl
When you remove abc, the mail does work.
Michael
2008-07-05 21:32:20 UTC
Permalink
Post by Wimpie
Post by Michael
I've seen the Lazy H mentioned in many antenna books over the years,
so I decided to try one on 10 meters. According to the ARRL handbook
the Lazy H is two collinear elements stacked on above the other, Each
collinear element is made up of two 1/2 wave elements. I chose to
use 5/8 wave spacing between the top and bottom elements. I connected
the top and bottom elements with 450 ohm 16 gauge stranded ladder line
(window line). After building the antenna I verified connectivity
between the top and bottom right elements and the top and bottom left
elements. I color coded the end insulators on each side so I could
easily see which top and bottom elements were connected to each other.
The antenna book says to connect the 450 ohm ladder line from the
antenna tuner to the middle of the 450 ladder line that connects top
and bottom elements. Ok done. Now I put up the antenna and make sure
the top and bottom elements are in phase. That is both left connected
elements are on the left and both right connected element are on the
right. I also make sure there is no twist in the ladder line
connecting the top and bottom elements. I also checked the other
ends of the 450 ohm ladder line feeding the antenna has connectivity
at the antenna, and the left and right sides of the ladder line do not
have connectivity. The 450 ohm ladder line feeding the antenna is
about 200 feet long.
Now I bring the 450 ohm feedline in to the house, hook it to my
Dentron MT-2000 antenna tuner with the 4:1 balun inside, tune it up,
and it sucks! Both my half wave horizontal dipole and my Solarcon
Max-2000 blow it away on incoming skip even in the preferred direction
of the lazy H. I rechecked my connections and the lengths of the
elements and spacing and they are correct. I did take in to account
the velocity factor of the 450 ladder line that connects the top
elements to the bottom elements. The antenna book says the length of
the 450 ladder lien between the antenna and the antenna tuner can e
any lenght.
The bottom element is at least 1/2 wave of the ground, and the top
element is 5/8ths wave above that. What did I do wrong?
Michael
Hi Michael,
Normally spoken the feedline between top to bottom elements is
0.5lambda long, without twist, feeding in the middle. The path from
feedpoint to end of the radiation elements is 0.75 lambda, giving an
almost real low input impedance (on order of 30 Ohms, depending on
thickness of radiating elements). In fact you have two full wave
dipoles fed in phase that give most radiation (ground ignored)
perpendicular to the array (bidirectional). There is a vertical null
Why choosing 5/8 lambda vertical element spacing? You create a
vertical lobe and a null in the elevation radiation pattern under
about 53 degrees. You also get a strong reactive input impedance, but
this may not be a problem with the ladder line.
Did you do some indicative field strength measurements (diode
detector) to find out whether it (and the elements) do(es) radiate
(comparing to the other antennas)? It may also reveal some hidden
things.
Maybe somebody knows a loss figure for your ladder line (at 28 MHz) to
assess the losses in the line (200ft part) because of bad VSWR.
Best regards,
Wim
PA3DJSwww.tetech.nl
When you remove abc, the mail does work.
Hi Wim,
According to the ARRL handbook the highest gain is achieve with a
5/8ths wave spacing between the upper and lower elements. The
handbook gives the following figures for estimated gain.

3/8 wave spacing = 4.4 dbd
1/2 wave spacing = 5.9 dbd
5/8 wave spacing = 6.7 dbd
3/4 wave spacing = 6.6 dbd

EZNEC shows a similar gain peak with a 5/8th wave spacing between the
top and bottom elements.

It seems to works on 14 MHz (stacked dipoles at 14 MHz), but on 10
meters the single 10 meter dipole blows it away.
Michael
2008-07-06 01:45:55 UTC
Permalink
Post by Michael
Post by Wimpie
Post by Michael
I've seen the Lazy H mentioned in many antenna books over the years,
so I decided to try one on 10 meters. According to the ARRL handbook
the Lazy H is two collinear elements stacked on above the other, Each
collinear element is made up of two 1/2 wave elements. I chose to
use 5/8 wave spacing between the top and bottom elements. I connected
the top and bottom elements with 450 ohm 16 gauge stranded ladder line
(window line). After building the antenna I verified connectivity
between the top and bottom right elements and the top and bottom left
elements. I color coded the end insulators on each side so I could
easily see which top and bottom elements were connected to each other.
The antenna book says to connect the 450 ohm ladder line from the
antenna tuner to the middle of the 450 ladder line that connects top
and bottom elements. Ok done. Now I put up the antenna and make sure
the top and bottom elements are in phase. That is both left connected
elements are on the left and both right connected element are on the
right. I also make sure there is no twist in the ladder line
connecting the top and bottom elements. I also checked the other
ends of the 450 ohm ladder line feeding the antenna has connectivity
at the antenna, and the left and right sides of the ladder line do not
have connectivity. The 450 ohm ladder line feeding the antenna is
about 200 feet long.
Now I bring the 450 ohm feedline in to the house, hook it to my
Dentron MT-2000 antenna tuner with the 4:1 balun inside, tune it up,
and it sucks! Both my half wave horizontal dipole and my Solarcon
Max-2000 blow it away on incoming skip even in the preferred direction
of the lazy H. I rechecked my connections and the lengths of the
elements and spacing and they are correct. I did take in to account
the velocity factor of the 450 ladder line that connects the top
elements to the bottom elements. The antenna book says the length of
the 450 ladder lien between the antenna and the antenna tuner can e
any lenght.
The bottom element is at least 1/2 wave of the ground, and the top
element is 5/8ths wave above that. What did I do wrong?
Michael
Hi Michael,
Normally spoken the feedline between top to bottom elements is
0.5lambda long, without twist, feeding in the middle. The path from
feedpoint to end of the radiation elements is 0.75 lambda, giving an
almost real low input impedance (on order of 30 Ohms, depending on
thickness of radiating elements). In fact you have two full wave
dipoles fed in phase that give most radiation (ground ignored)
perpendicular to the array (bidirectional). There is a vertical null
Why choosing 5/8 lambda vertical element spacing? You create a
vertical lobe and a null in the elevation radiation pattern under
about 53 degrees. You also get a strong reactive input impedance, but
this may not be a problem with the ladder line.
Did you do some indicative field strength measurements (diode
detector) to find out whether it (and the elements) do(es) radiate
(comparing to the other antennas)? It may also reveal some hidden
things.
Maybe somebody knows a loss figure for your ladder line (at 28 MHz) to
assess the losses in the line (200ft part) because of bad VSWR.
Best regards,
Wim
PA3DJSwww.tetech.nl
When you remove abc, the mail does work.
Hi Wim,
According to the ARRL handbook the highest gain is achieve with a
5/8ths wave spacing between the upper and lower elements. The
handbook gives the following figures for estimated gain.
3/8 wave spacing = 4.4 dbd
1/2 wave spacing = 5.9 dbd
5/8 wave spacing = 6.7 dbd
3/4 wave spacing = 6.6 dbd
EZNEC shows a similar gain peak with a 5/8th wave spacing between the
top and bottom elements.
It seems to works on 14 MHz (stacked dipoles at 14 MHz), but on 10
meters the single 10 meter dipole blows it away.
Well I tried reducing the spacing between the top and bottom elements
to 1/2 wave spacing, but it still did not seem to make any
difference.

I've noticed in the past when working with ladder line that tuning an
antenna with an antenna tuner from about 14 MHz and down brings up the
receive verses by-passing the tuner completely, but that never seems
to happen once you reach 10 meters. I wonder if that has something to
do with it.
Hal Rosser
2008-07-06 02:44:32 UTC
Permalink
I'm not sure, but if the Lazy H has Horizontal polarity and the folks you're
trying to communicate with are using Verticals, there may be quite a bit of
signal loss.
Since you mentioned it was for 11 meters, can we assume you're trying to
communicate without using 'skip'?
Michael
2008-07-06 02:58:06 UTC
Permalink
Post by Hal Rosser
I'm not sure, but if the Lazy H has Horizontal polarity and the folks you're
trying to communicate with are using Verticals, there may be quite a bit of
signal loss.
Since you mentioned it was for 11 meters, can we assume you're trying to
communicate without using 'skip'?
It meant for skip. I mean to type 10 meters. Old habits die hard as
I started on the CB band.

.
John Smith
2008-07-06 03:14:49 UTC
Permalink
Post by Michael
Post by Hal Rosser
I'm not sure, but if the Lazy H has Horizontal polarity and the folks you're
trying to communicate with are using Verticals, there may be quite a bit of
signal loss.
Since you mentioned it was for 11 meters, can we assume you're trying to
communicate without using 'skip'?
It meant for skip. I mean to type 10 meters. Old habits die hard as
I started on the CB band.
.
In my area, San Joaquin Valley, Ca--most 10m is on verticals ... while
the guys running the "one size fits all" antennas--or, 80-10m (or, even
160-10m!) are mostly horiz--since a 10m is so easy, they slap up a 10m
vertical also.

The "myth" that most noise is vertically polarized--well, I never
subscribed to that (but, when I was a kid, I first believed it!) Most
runs off above ground power-lines are even, somewhere, around a 45
degree angle (and, above ground power-lines are ALWAYS horiz polarized!
Drive around and look, maybe they do it different in your area ... ???

And, now, most power-lines have went under-ground in my area ...
vertical is fine with me and I don't send my signal skyward or into the
ground, where it may reflect into the stratosphere anyway ...

Regards,
JS
John Smith
2008-07-06 05:09:11 UTC
Permalink
Post by John Smith
Post by Michael
Post by Hal Rosser
I'm not sure, but if the Lazy H has Horizontal polarity and the folks you're
trying to communicate with are using Verticals, there may be quite a bit of
signal loss.
Since you mentioned it was for 11 meters, can we assume you're trying to
communicate without using 'skip'?
It meant for skip. I mean to type 10 meters. Old habits die hard as
I started on the CB band.
.
In my area, San Joaquin Valley, Ca--most 10m is on verticals ... while
the guys running the "one size fits all" antennas--or, 80-10m (or, even
160-10m!) are mostly horiz--since a 10m is so easy, they slap up a 10m
vertical also.
The "myth" that most noise is vertically polarized--well, I never
subscribed to that (but, when I was a kid, I first believed it!) Most
runs off above ground power-lines are even, somewhere, around a 45
degree angle (and, above ground power-lines are ALWAYS horiz polarized!
Drive around and look, maybe they do it different in your area ... ???
And, now, most power-lines have went under-ground in my area ...
vertical is fine with me and I don't send my signal skyward or into the
ground, where it may reflect into the stratosphere anyway ...
Regards,
JS
And, I almost forgot, ever attempt to get a horiz 20m+ ant on a mobile?
(I haven't!)

Regards,
JS
Michael
2008-07-06 03:01:45 UTC
Permalink
Post by Hal Rosser
I'm not sure, but if the Lazy H has Horizontal polarity and the folks you're
trying to communicate with are using Verticals, there may be quite a bit of
signal loss.
Since you mentioned it was for 11 meters, can we assume you're trying to
communicate without using 'skip'?
It is meant for skip. I typed 10 meters at the start of the message,
but 11 meters in the Subject line. Old habits die hard as I started
on the CB band.
Wimpie
2008-07-06 10:52:17 UTC
Permalink
Post by Michael
Post by Hal Rosser
I'm not sure, but if the Lazy H has Horizontal polarity and the folks you're
trying to communicate with are using Verticals, there may be quite a bit of
signal loss.
Since you mentioned it was for 11 meters, can we assume you're trying to
communicate without using 'skip'?
It is meant for skip. I typed 10 meters at the start of the message,
but 11 meters in the Subject line. Old habits die hard as I started
on the CB band.
Hello Michael,

You mentioned that even your hor. dipole blows away the Lazy H (also
for good orientation). This rules out every influence because of
minimum elevation angle of main beam versus ground conductivity/
permittivity.

I assume that you are talking about several S-points. There must be
something really wrong. The dipole close to ground will have some
different impedance (then the upper). This will cause some phase
error, but this should not lead to a drastic reduction of overall
gain.

According to your postings, the construction is OK (no twist, feeding
in the middle). I also assume that you have some spacing between the
5/8 lambda long vertical line and the actual feed line (of 200ft), to
avoid coupling between the two.

It can be the line, or the tuner/balun. Line Losses increase and when
your VSWR in the line is very high, this may increase the overall loss
in your 450 Ohm feed line. If possible compare the field strength of
your hor. dipole with field strength of the lazy H.

Other option is to find an unused frequency en put in lots of power
and look for temperature increase.

Best regards,

Wim
PA3DJS
www.tetech.nl
The mail does function when you remove abc
Cecil Moore
2008-07-06 04:04:50 UTC
Permalink
Post by Michael
According to the ARRL handbook the highest gain is achieve with a
5/8ths wave spacing between the upper and lower elements. The
handbook gives the following figures for estimated gain.
3/8 wave spacing = 4.4 dbd
1/2 wave spacing = 5.9 dbd
5/8 wave spacing = 6.7 dbd
3/4 wave spacing = 6.6 dbd
It seems to works on 14 MHz (stacked dipoles at 14 MHz), but on 10
meters the single 10 meter dipole blows it away.
Quoting the ARRL Antenna Book: "It should be designed
for the higher of the two frequencies using 3/4 lamda
spacing between parallel elements. It will then operate
on the lower frequency ... with 3/8 lamda spacing.

If you have 5/8 lamda spacing on 20m, you will have
5/4 lamda spacing on 10m with poor performance.
--
73, Cecil http://www.w5dxp.com
n***@wt.net
2008-07-06 05:59:33 UTC
Permalink
Post by Cecil Moore
Post by Michael
According to the ARRL handbook the highest gain is achieve with a
5/8ths wave spacing between the upper and lower elements. The
handbook gives the following figures for estimated gain.
3/8 wave spacing = 4.4 dbd
1/2 wave spacing = 5.9 dbd
5/8 wave spacing = 6.7 dbd
3/4 wave spacing = 6.6 dbd
It seems to works on 14 MHz (stacked dipoles at 14 MHz), but on 10
meters the single 10 meter dipole blows it away.
Quoting the ARRL Antenna Book: "It should be designed
for the higher of the two frequencies using 3/4 lamda
spacing between parallel elements. It will then operate
on the lower frequency ... with 3/8 lamda spacing.
If you have 5/8 lamda spacing on 20m, you will have
5/4 lamda spacing on 10m with poor performance.
--
73, Cecil http://www.w5dxp.com
Not only that, but will depend if feeding end fire, or broadside.
It's only as a broadside array that max gain is at 5/8 wl
spacing.
And he is feeding his as an end fire array. The elements would
need to be end to end IE: collinear, array to be fed as a broadside
array.
As an end fire, the spacing must be quite a bit closer. If I remember
right, max gain with an end fire array is appx 1/8 wl spacing.
But from my own experimenting around with them, it's not
ultra critical as far as getting them to work.
In my case, I was feeding each element with a separate
feed line, and changing lengths to steer the array.
It was quite crude, but worked pretty well.
In my case, I tried to compromise on the spacing so I
could feed it both end fire, and broadside. I think I used
about 1/4 wl.
I also used about the same scheme on 10m, using two
5/8 wl ground planes. I forgot the exact spacing I used.
It was more dictated by available mast/.vent pipe locations
more than trying to get an exact length.
But it was a compromise spacing, and I fed it both ways
depending on the pattern I wanted.
n***@wt.net
2008-07-06 06:16:58 UTC
Permalink
Post by n***@wt.net
But it was a compromise spacing, and I fed it both ways
depending on the pattern I wanted.
Just thinking about another thing.. I think feeding in phase
would give a bi directional pattern, but if he wanted an
omni directional pattern, I think he'd have to have the elements
90 degrees out of phase. But I fergot...
He could fire up eznec demo or whatever and he can
quickly get a pretty good idea what to expect in theory
with any particular spacing and phasing.
He could crudely steer the pattern if he used various
length feeders to each element.
Some also use the "L/C" phasing boxes to steer the
pattern. Again fairly crude compared to some methods,
but it will work. Just don't expect perfect textbook patterns.
You have to take what you get...
The ARRL antenna book has better methods if want
cleaner patterns.
John Smith
2008-07-06 06:33:41 UTC
Permalink
Post by n***@wt.net
Post by n***@wt.net
But it was a compromise spacing, and I fed it both ways
depending on the pattern I wanted.
Just thinking about another thing.. I think feeding in phase
would give a bi directional pattern, but if he wanted an
omni directional pattern, I think he'd have to have the elements
90 degrees out of phase. But I fergot...
He could fire up eznec demo or whatever and he can
quickly get a pretty good idea what to expect in theory
with any particular spacing and phasing.
He could crudely steer the pattern if he used various
length feeders to each element.
Some also use the "L/C" phasing boxes to steer the
pattern. Again fairly crude compared to some methods,
but it will work. Just don't expect perfect textbook patterns.
You have to take what you get...
The ARRL antenna book has better methods if want
cleaner patterns.
Or, if you don't wish the built-in limitations of Eznec (the demo
version), try MMANA GAL. Will feed the same data to the nec engine(s.)

Regards,
JS
John Smith
2008-07-06 06:35:23 UTC
Permalink
Post by John Smith
Or, if you don't wish the built-in limitations of Eznec (the demo
version), try MMANA GAL. Will feed the same data to the nec engine(s.)
Regards,
JS
Forgot, should have given a URL to go with that:

http://mmhamsoft.amateur-radio.ca/mmana/index.htm

Regards,
JS
n***@wt.net
2008-07-06 06:48:08 UTC
Permalink
On Jul 6, 1:16 am, ***@wt.net wrote:

Ya know what, I guess he is running as a broadside
array after all.. I was thinking he had the elements
horizontal, but after rereading the first post, he does
have them stacked.
And if they were in phase, that should be a broadside
array.
Sooo... I finally decided to check it in the program using
two 1/2 wave elements for 10m, with the lower element
at 1/2 wave up, "16 ft", and the upper one at appx 5/8 wave
higher. "37 ft"
Using the single lower element alone, I got 2.08 dbi.
Using both in phase, I got 6.8 dbi.. So, it should work
as planned.. Not sure what the problem would be though,
unless you have coupling problems with other metal in
the area, etc..
Michael
2008-07-06 11:44:18 UTC
Permalink
Post by Cecil Moore
Post by Michael
According to the ARRL handbook the highest gain is achieve with a
5/8ths wave spacing between the upper and lower elements. The
handbook gives the following figures for estimated gain.
3/8 wave spacing = 4.4 dbd
1/2 wave spacing = 5.9 dbd
5/8 wave spacing = 6.7 dbd
3/4 wave spacing = 6.6 dbd
It seems to works on 14 MHz (stacked dipoles at 14 MHz), but on 10
meters the single 10 meter dipole blows it away.
Quoting the ARRL Antenna Book: "It should be designed
for the higher of the two frequencies using 3/4 lamda
spacing between parallel elements. It will then operate
on the lower frequency ... with 3/8 lamda spacing.
If you have 5/8 lamda spacing on 20m, you will have
5/4 lamda spacing on 10m with poor performance.
--
73, Cecil http://www.w5dxp.com
It is designed for the higher band.
Michael
2008-07-06 17:55:48 UTC
Permalink
Post by Michael
I've seen the Lazy H mentioned in many antenna books over the years,
so I decided to try one on 10 meters. According to the ARRL handbook
the Lazy H is two collinear elements stacked on above the other, Each
collinear element is made up of two 1/2 wave elements. I chose to
use 5/8 wave spacing between the top and bottom elements. I connected
the top and bottom elements with 450 ohm 16 gauge stranded ladder line
(window line). After building the antenna I verified connectivity
between the top and bottom right elements and the top and bottom left
elements. I color coded the end insulators on each side so I could
easily see which top and bottom elements were connected to each other.
The antenna book says to connect the 450 ohm ladder line from the
antenna tuner to the middle of the 450 ladder line that connects top
and bottom elements. Ok done. Now I put up the antenna and make sure
the top and bottom elements are in phase. That is both left connected
elements are on the left and both right connected element are on the
right. I also make sure there is no twist in the ladder line
connecting the top and bottom elements. I also checked the other
ends of the 450 ohm ladder line feeding the antenna has connectivity
at the antenna, and the left and right sides of the ladder line do not
have connectivity. The 450 ohm ladder line feeding the antenna is
about 200 feet long.
Now I bring the 450 ohm feedline in to the house, hook it to my
Dentron MT-2000 antenna tuner with the 4:1 balun inside, tune it up,
and it sucks! Both my half wave horizontal dipole and my Solarcon
Max-2000 blow it away on incoming skip even in the preferred direction
of the lazy H. I rechecked my connections and the lengths of the
elements and spacing and they are correct. I did take in to account
the velocity factor of the 450 ladder line that connects the top
elements to the bottom elements. The antenna book says the length of
the 450 ladder lien between the antenna and the antenna tuner can e
any lenght.
The bottom element is at least 1/2 wave of the ground, and the top
element is 5/8ths wave above that. What did I do wrong?
Michael
I found an article that shows using a 1/4 wave matching stub at the
bottom of an end fire Lazy H with 1/2 wave spacing. Perhaps even
ladder line transmission line needs a matching stub.

http://www.ve7zsa.net/technical/advsgtxt/c15antenna_r00.htm
Michael
2008-07-06 18:07:51 UTC
Permalink
Post by Michael
Post by Michael
I've seen the Lazy H mentioned in many antenna books over the years,
so I decided to try one on 10 meters. According to the ARRL handbook
the Lazy H is two collinear elements stacked on above the other, Each
collinear element is made up of two 1/2 wave elements. I chose to
use 5/8 wave spacing between the top and bottom elements. I connected
the top and bottom elements with 450 ohm 16 gauge stranded ladder line
(window line). After building the antenna I verified connectivity
between the top and bottom right elements and the top and bottom left
elements. I color coded the end insulators on each side so I could
easily see which top and bottom elements were connected to each other.
The antenna book says to connect the 450 ohm ladder line from the
antenna tuner to the middle of the 450 ladder line that connects top
and bottom elements. Ok done. Now I put up the antenna and make sure
the top and bottom elements are in phase. That is both left connected
elements are on the left and both right connected element are on the
right. I also make sure there is no twist in the ladder line
connecting the top and bottom elements. I also checked the other
ends of the 450 ohm ladder line feeding the antenna has connectivity
at the antenna, and the left and right sides of the ladder line do not
have connectivity. The 450 ohm ladder line feeding the antenna is
about 200 feet long.
Now I bring the 450 ohm feedline in to the house, hook it to my
Dentron MT-2000 antenna tuner with the 4:1 balun inside, tune it up,
and it sucks! Both my half wave horizontal dipole and my Solarcon
Max-2000 blow it away on incoming skip even in the preferred direction
of the lazy H. I rechecked my connections and the lengths of the
elements and spacing and they are correct. I did take in to account
the velocity factor of the 450 ladder line that connects the top
elements to the bottom elements. The antenna book says the length of
the 450 ladder lien between the antenna and the antenna tuner can e
any lenght.
The bottom element is at least 1/2 wave of the ground, and the top
element is 5/8ths wave above that. What did I do wrong?
Michael
I found an article that shows using a 1/4 wave matching stub at the
bottom of an end fire Lazy H with 1/2 wave spacing. Perhaps even
ladder line transmission line needs a matching stub.
http://www.ve7zsa.net/technical/advsgtxt/c15antenna_r00.htm
Looks like another user had similar problems with a Lazy H using 450
ladder line all the way to the tuner. Like me his will tune on 14 MHz
where it is basically stacked dipoles, but once you get to 10 meters
it is a no go. He tried 450 ohm ladder line to a balun as well.

http://forums.qrz.com/archive/index.php/t-135914.html
Michael
2008-07-06 19:30:13 UTC
Permalink
Post by Michael
Post by Michael
I've seen the Lazy H mentioned in many antenna books over the years,
so I decided to try one on 10 meters. According to the ARRL handbook
the Lazy H is two collinear elements stacked on above the other, Each
collinear element is made up of two 1/2 wave elements. I chose to
use 5/8 wave spacing between the top and bottom elements. I connected
the top and bottom elements with 450 ohm 16 gauge stranded ladder line
(window line). After building the antenna I verified connectivity
between the top and bottom right elements and the top and bottom left
elements. I color coded the end insulators on each side so I could
easily see which top and bottom elements were connected to each other.
The antenna book says to connect the 450 ohm ladder line from the
antenna tuner to the middle of the 450 ladder line that connects top
and bottom elements. Ok done. Now I put up the antenna and make sure
the top and bottom elements are in phase. That is both left connected
elements are on the left and both right connected element are on the
right. I also make sure there is no twist in the ladder line
connecting the top and bottom elements. I also checked the other
ends of the 450 ohm ladder line feeding the antenna has connectivity
at the antenna, and the left and right sides of the ladder line do not
have connectivity. The 450 ohm ladder line feeding the antenna is
about 200 feet long.
Now I bring the 450 ohm feedline in to the house, hook it to my
Dentron MT-2000 antenna tuner with the 4:1 balun inside, tune it up,
and it sucks! Both my half wave horizontal dipole and my Solarcon
Max-2000 blow it away on incoming skip even in the preferred direction
of the lazy H. I rechecked my connections and the lengths of the
elements and spacing and they are correct. I did take in to account
the velocity factor of the 450 ladder line that connects the top
elements to the bottom elements. The antenna book says the length of
the 450 ladder lien between the antenna and the antenna tuner can e
any lenght.
The bottom element is at least 1/2 wave of the ground, and the top
element is 5/8ths wave above that. What did I do wrong?
Michael
I found an article that shows using a 1/4 wave matching stub at the
bottom of an end fire Lazy H with 1/2 wave spacing. Perhaps even
ladder line transmission line needs a matching stub.
http://www.ve7zsa.net/technical/advsgtxt/c15antenna_r00.htm
Yep. Looks like that is it. Unfortunately I am out of time for this
weekend, so I'll have to try it out next weekend. According to an
article I found I need a closed end 1/4 matching stub. I'll update
here after I try it out next weekend.

-Michael
t***@qmc.ph.msstate.edu
2008-07-07 14:10:50 UTC
Permalink
Post by Michael
The bottom element is at least 1/2 wave of the ground, and the top
element is 5/8ths wave above that. What did I do wrong?
I suspect with your long feedline length (200 ft you said?), and the
probably very high SWR on the feedline, you have significant feedline loss.

Also, are the elements really horizontal? Or are they closer to inverted V's?

Tor
N4OGW
Dave Oldridge
2008-07-10 04:33:28 UTC
Permalink
Post by Michael
I've seen the Lazy H mentioned in many antenna books over the years,
so I decided to try one on 10 meters. According to the ARRL handbook
the Lazy H is two collinear elements stacked on above the other, Each
collinear element is made up of two 1/2 wave elements. I chose to
use 5/8 wave spacing between the top and bottom elements. I connected
the top and bottom elements with 450 ohm 16 gauge stranded ladder line
(window line). After building the antenna I verified connectivity
between the top and bottom right elements and the top and bottom left
elements. I color coded the end insulators on each side so I could
easily see which top and bottom elements were connected to each other.
The antenna book says to connect the 450 ohm ladder line from the
antenna tuner to the middle of the 450 ladder line that connects top
and bottom elements. Ok done. Now I put up the antenna and make sure
the top and bottom elements are in phase. That is both left connected
elements are on the left and both right connected element are on the
right. I also make sure there is no twist in the ladder line
connecting the top and bottom elements. I also checked the other
ends of the 450 ohm ladder line feeding the antenna has connectivity
at the antenna, and the left and right sides of the ladder line do not
have connectivity. The 450 ohm ladder line feeding the antenna is
about 200 feet long.
Now I bring the 450 ohm feedline in to the house, hook it to my
Dentron MT-2000 antenna tuner with the 4:1 balun inside, tune it up,
and it sucks! Both my half wave horizontal dipole and my Solarcon
Max-2000 blow it away on incoming skip even in the preferred direction
of the lazy H. I rechecked my connections and the lengths of the
elements and spacing and they are correct. I did take in to account
the velocity factor of the 450 ladder line that connects the top
elements to the bottom elements. The antenna book says the length of
the 450 ladder lien between the antenna and the antenna tuner can e
any lenght.
The bottom element is at least 1/2 wave of the ground, and the top
element is 5/8ths wave above that. What did I do wrong?
Have you tried lengthening or shortening the line by about 4 1/2 feet?
It may be simply that the length of the line is resulting in an impedance
your tuner cannot match.

I think, given the nature of the antenna and the length of your line, you
can probably expect about 3 dB losses on a dry line and close to 10 on a
wet one.
--
Dave Oldridge+
ICQ 1800667
VA7CZ
Loading...