On May 30, 2:44*pm, Baron wrote:
Michael Inscribed thus:











* Well I've worked with the center fed Lazy H antenna design on 10
meters for several few weeks now. *I tried 1/2 wave spacing between
the top and bottom elements, 5/8th wave spacing between the top and
bottom elements, I put it up at 40 feet and 50 feet at the top wire, I
tried different lengths of 450 ohm feed-line, and this antenna
consistently under performs a 1/2 wave dipole cut for the same
frequency. *A simple 1/2 wave dipole consistently out performs the
center fed version of Lazy H antenna even when the Lazy H is given a
20 foot height advantage over the lowly dipole. I even put up the Lazy
H in two completely different locations over 180 miles apart. I also
tried two completely different antenna tuners (Dentron MT-3000a and
Drake MN-75 with the 4:1 balun installed). Out of over 200 A/B test
the Lazy H antenna only out performed the dipole on one test with a
station in Texas just before the propagation faded out for the day,
The next day when the propagation was back I heard the same station on
the same frequency and the dipole out performed the Lazy H for the
rest of the day. * I'm not sure what special propagation mode is
required for the Lazy H to have some gain through some pin hole
direction, but the version of the Lazy H center fed with 450 ohm
ladder line back to the antenna tuner is a complete failure. *I even
re-built the antenna from scratch using a different piece 450 ladder
line for the inter connecting piece. I also verified the length of
each 1/2 wave section with a tape measure. I verified with an ohm
meter that the top left element was connected to the bottom left
element and the right top element was connected to the bottom right
element. *I verified there was no unexpected connectivity between the
left and right elements, and I verified both sides of the ladder line
were connected back to the antenna tuner. *I made sure there was no
twist in the ladder line connecting the top and bottom elements.
* I would like to petition the ARRL to remove the center fed Lazy H
from the antenna handbook as it clearly does not work as specified. *A
lowly mono band dipole on the same design frequency will consistently
out perform the center feed Lazy H even when the Lazy H is given a 20
foot height advantage on10 meters.
* Before any of you reply with charts and graphs from EZNEC software,
turn off your computer, go out in the back yard, and actually build a
center fed Lazy H antenna with 450 ladder line all the way back to the
antenna tuner. *Then do real world A/B comparisons with a plain old
mono band dipole cut for the same frequency, and you will find I am
telling the truth. *The center fed Lazy H does not have any gain over
a 1/2 wave dipole broadside to the antenna. None.

Here is what you will fine if you actually build the center fed Lazy H
and compare it to a 1/2 wave mono band dipole cut for the same same
frequency;

1) Your tuner will have to use extreme setting to match the Lazy H.
2) In some instances the tuner will not be able to match the Lazy H
depending on the length of the ladder line feeding the antenna. You
may have to increase or decrease the length of the ladder line feeding
the Lazy H to get your antenna tuner to match it.
3) A 1/2 wave dipole will beat the Lazy H 99.99 percent of the time in
it's favored direction even if the Lazy H is given a 20 foot height
advantage over the dipole.
4) An extended double zepp with a 450 ohm matching section back to a
1:1 balun and then to 50 ohm coax cut for the same frequency and hung
from the same ropes previously used to support the Lazy H will blow
the Lazy H in the dirt.

In a nutshell, this antenna sucks!

Michael Rawls
KS4HY

Tried mounting it horizontally ?

--
Best Regards:
* * * * * * * * * * * * * Baron.


Hi Michael,

I'm sorry to hear you think the lazy-H sucks. I used one on 20m years
ago and it worked just fine--and no trouble in matching it with a
tuner.

However, I have a suggestion: Let's say you space the upper and lower
radiating elements by 180°, which is 1/2wl. If you now use 450-ohm
window line, the velocity factor for the line attaching the two
elements together makes the electrical length of the line greater than
1/2wl, which means the phasing between the upper and lower elements is
no longer correct, and therefore will not provide the expected gain.
I'm not sure how much phasing error that will produce, but it's an
issue you should consider. Correctly constructed, the lazy-H will
definitely out perform a 1/2wl dipole, so if it doesn't for you there
is sum ting definitely wong!

If you feed at the center of the line connecting the two radiating
elements the phasing will be correct regardless of the velocity
factor, because the length from the center feed point on the
connecting line will be the same from that point to each radiating
element. With this configuration of feeding don't put a twist in the
connecting line--the two radiating elements MUST be fed IN PHASE! If
they're fed out of phase the array will look like an Adcock direction-
finding antenna, with a deep null in the radiation pattern in the
broadside direction.

Just my thoughts,

Walt, W2DU