If I had to choose, I'd always choose a half-wave 80m vertical in
preference to a half-wave dipole.

In general, I'd prefer the dipole on 80m. But I work mostly
close in within say 600 miles on average. A dipole will smoke
most verticals at those short distances. If the dipole is at least
30-40 ft off the ground, it will still be capable of dx.
If I worked all dx on 80, I'd rather have the vertical, but being I
don't,
I prefer the dipole.
Each band is different, and it always depends on what path/distance
etc, I want to work as far as the preferred antenna.
In general, I'd prefer the vertical on 160m.
Dipole for 80 and 40, and usually 20.
I've tried both a 1/4 GP and a dipole on 20m for average use,
and found I prefer the dipole. Probably ditto for 17,15.
But on 10m, I prefer a 1/2, 5/8 vertical if I can't have a beam.
On 10m, you see quite a bit of local chatter, and most tend
to run vertical if they want a decent ground/space wave.
It also gives them a good dx signal. If you run a dipole on 10m,
your long haul will be good, but local operation fairly poor.
There really is no best type antenna except to suit the job at
hand. If I'm on 40m in the day, give me me a good dipole,
loop, etc . But 40m at night 800-1000 miles to the coasts?
I'd rather be sitting in my truck running the mobile. No joke.
It will do a better job vs my appx 40 ft tall dipole. That
was tested over and over again. No fluke of the band cdx.
On 40 at night, which is best will nearly always be distance
determined. Look at the lowly efficiency of the mobile vs
the dipole. At night, it doesn't really mean squat. What matters
is that you have radiation at the angle you need to make that
hop. My mobile spits more rf at the desired angle than my
40 ft high dipole does at those semi low angles despite being
half crippled as far as efficiency vs a full size antenna.
So polarization is nothing to ignore if you want the best
bang for the buck. I bet my mobile ant sitting sideways would
be pretty lame in that case. Or say take two like mobile antennas
and make a short dipole. It would stink up the place on those
long hauls vs the normal vertical mobile antenna. But it might be
slightly better in the day working 200 miles away.
The best is to have both. And use a switch to be able to
quickly compare. You will see some interesting things as
far as band cdx, signal fluctuations, etc over time.
It really boils down to using experience working the various bands,
at the various times of day, season, to know which will likely
be the best at a given time. It's 1.49 in the AM here right now.
If I had to get on 40m right now, give me the vertical any day.
That would change in a few hours though when I started losing the
long haul stuff and had it replaced by the various old farts and
rednecks I work on a more local scale. :/ I'd then be on the dipole.
MK

wrote:
If I had to choose, I'd always choose a half-wave 80m vertical in
preference to a half-wave dipole.


In general, I'd prefer the dipole on 80m. But I work mostly
close in within say 600 miles on average. A dipole will smoke
most verticals at those short distances. If the dipole is at least
30-40 ft off the ground, it will still be capable of dx.
If I worked all dx on 80, I'd rather have the vertical, but being I
don't,
I prefer the dipole.
Each band is different, and it always depends on what path/distance
etc, I want to work as far as the preferred antenna.
In general, I'd prefer the vertical on 160m.
Dipole for 80 and 40, and usually 20.
I've tried both a 1/4 GP and a dipole on 20m for average use,
and found I prefer the dipole. Probably ditto for 17,15.
But on 10m, I prefer a 1/2, 5/8 vertical if I can't have a beam.
On 10m, you see quite a bit of local chatter, and most tend
to run vertical if they want a decent ground/space wave.
It also gives them a good dx signal. If you run a dipole on 10m,
your long haul will be good, but local operation fairly poor.
There really is no best type antenna except to suit the job at
hand. If I'm on 40m in the day, give me me a good dipole,
loop, etc . But 40m at night 800-1000 miles to the coasts?
I'd rather be sitting in my truck running the mobile. No joke.
It will do a better job vs my appx 40 ft tall dipole. That
was tested over and over again. No fluke of the band cdx.
On 40 at night, which is best will nearly always be distance
determined. Look at the lowly efficiency of the mobile vs
the dipole. At night, it doesn't really mean squat. What matters
is that you have radiation at the angle you need to make that
hop. My mobile spits more rf at the desired angle than my
40 ft high dipole does at those semi low angles despite being
half crippled as far as efficiency vs a full size antenna.
So polarization is nothing to ignore if you want the best
bang for the buck. I bet my mobile ant sitting sideways would
be pretty lame in that case. Or say take two like mobile antennas
and make a short dipole. It would stink up the place on those
long hauls vs the normal vertical mobile antenna. But it might be
slightly better in the day working 200 miles away.
The best is to have both. And use a switch to be able to
quickly compare. You will see some interesting things as
far as band cdx, signal fluctuations, etc over time.
It really boils down to using experience working the various bands,
at the various times of day, season, to know which will likely
be the best at a given time. It's 1.49 in the AM here right now.
If I had to get on 40m right now, give me the vertical any day.
That would change in a few hours though when I started losing the
long haul stuff and had it replaced by the various old farts and
rednecks I work on a more local scale. :/ I'd then be on the dipole.


In support of Cecil's project of listening on a horizontal, while
transmitting on a vertical, I have tried an experiment this evening, and
will report on the results so far

While listening to an OK3 station this evening on 3.7995, I tuned two
separate radios to the frequency.

Radio 1 is an IC-745 with a Butternut HF6V. 20 some radials. decent
soil. Seems to work "well".

Radio 2 is an IC-761 on an OCF dipole. Also works pretty "well"


Noise level on the Vertical setup is S-8.

Noise level on the horizontal is S-4.

Mr. OK3 is at almost S-9 on the Vertical, and around S-7 to nearly S-8
on the horizontal.

Of course these two rigs have not been calibrated against each other.
So I can only say that at least from his location, he is putting a bit
stronger a signal (as far as the antenna is concerned) into the Middle
of Pennsylvania .

But here is the interesting thing. On the horizontal antenna, the
listening is a whole heckava lot more pleasant. Another item of interest
is that in a recent exchange between the OK3 and a VE3, I could catch
the Canadian station on my horizontal setup, while he was in the noise
on the vertical.

This is an early stage of the experiment, but
I believe that there is a lot to say with the lower noise on the
horizontal antenna station.

- 73 de Mike KB3EIA -

This is an early stage of the experiment, but
I believe that there is a lot to say with the lower noise on the
horizontal antenna station

Probably has a lot to do with the particular sites
though. It's quite possible to be near a noise source
that is mainly vertical polarized. In a case like that, it's
possible it could be a problem. But I never saw the difference
in noise levels you are seeing. At the worst, I might see
appx 2 S units, but sometimes it might only be one, or
even other times , nearly no difference at all. Most of
the noise I would see at this location is power line noise.
It seems to effect both horizontal and vertical nearly equally.
Probably cuz much is radiated by horizontal power lines.
I've never tested it, but I think if you are in a noiseless location,
the difference would be fairly small as far as meter readings
just measuring the average atmospheric noise. The reason I
say this is because sometimes I would see little difference in
noise between the two. But other times I might see more.
But you could see small differences just from the increase in
strength of dx signals. IE: if you had T-storms 1500 miles away,
it's quite likely the vertical will receive them stronger than the
horizontal due to the normal operation of the antennas.
Anyway, I don't totally consider what you see as the norm. "4 s units"
You probably have a local vertical noise source nearby. If it's power
line, etc, you might be able to track it down and get it fixed.
I'd be curious to see if you see the same 4 S unit noise difference
over a period of time. Like I say, mine would vary. But noise
never was much of a concern on mine. Never gave it much thought
at all. Kinda weird too being I'm in a big city, in a residential area.

Being mine was elevated at 36 ft at the base, I also had a pretty
good line of sight to any potential noise sources.
The tip of the radiator was at about 68 ft. As far as the VE being
better on the wire, that's probably fairly normal, being he wasn't dx.

Also, as a final note, while your butternut with 20 radials is ok, it
still
isn't quite up to the performance I saw with mine at 36 ft, using a
full size antenna. So I saw a larger signal increase on the dx than you

I bet. Mine was appx equal to a full length monopole with 60 radials,
if ground mounted. I'd have to look, but my ground may be a bit better
too. I'm right on the edge of being in a "30" zone. Of course, raising
efficiency raises s/n equally, but I noticed that I never saw the same
performance I had with the ground plane, when I ran the same full size
vertical on the ground with 32 radials. That antenna was about equal
to my dipoles at 1500 miles. Maybe a small bit better, but not any
2 S units worth like the GP was. So regardless of some saying the
number of radials is not too important, it must be, if you want the
best
performance. Sure made a difference here...
Either that, or elevating it above the surroundings makes the
difference.
Myself, I think it's about 75% the first, and 25% the second...
Elevating
the antenna for sure increased my local ground wave. I could work 50
miles away ground wave easy. I'd have cases in the daytime where I'd
lose locals due to the band stretching out. But I could still nail them
at
S 9 using the GP, where the dipole would be hard to read backscatter.
Of course, if the band was open short, I'd be 10-20-30 over 9 on the
dipole
to the same location.
Anyway, I guess you gotta use what works, but I don't think it's
totally
normal to see a huge difference in noise between vertical and
horizontal
unless something local is the culprit.
MK

My geometric argument that beyond distances of several hundred,
perhaps 500 miles, the vertical puts down a stronger signal and
receives stronger signals than the horizontal dipole cannot be
disputed.

If you can't be heard at 1000 miles or more using a dipole, you are
more likely to be heard using a vertical regardless of what antenna
the other fellow is using to receive. At great distances you are much
more likely to be heard using a vertical at the same average height
above its surroundings.

Signal to noise ratio does matter of course.

Local noise level is much greater than received from distance sources
for obvious reasons. Local noise is vertically polarised. It comes in
via groundwave.

Noise from a distance is randomly polarised. It comes in via the
ionosphere. So in towns and cities, with buildings wiring, overhead
power and phone lines, where most of us live, the vertical collects
more local noise. In the wide open countryside both types of antenna
tend to perform equally well on randomly polarised, distant noise
levels.

With distant noise and interference and distant signals, both types of
antenna result in the same signal to noise ratio in the receiver. But
the vertical antenna receives the stronger signal plus noise. If the
internal receiver noise is greater than the received signal plus noise
then the vertical antenna will win the contest.

However, there is another effect which sometimes gives the dipole the
advantage. It is multi-hop propagation.

The angle of elevation of the radio path increases with the number of
hops involved. The number of hops depends on the sun-angle and day or
nighttime. Across the States or across the Pacific, for example, the
propagation loss can be much less with 2 or 3 hops than it is with one
or two hops. Waves sometimes bounce between the F2 and E layers. The
increase in elevation angle favours the horizontal dipole. And how
many amateurs know the number of hops involved at any point in time?

But what eventually favours the vertical over the dipole is their
respective service areas. The service area covered by the vertical is
many times, far greater than the dipole and so is the world wide
distribution of radio amateurs and short-wave listeners.

We have now returned to the simplistic but precise Geometry of the
ancient Egyptians and Greeks. ;o)
----
Reg, G4FGQ.

Reg wrote:
"If you can`t be heard at 1000 miles or more using a dipole, you are
more likely to be heard using a vertical regardless of what the other
fellow is using to receive."

That must not always be the case. Otherwise all the shortwave broadcast
stations I`ve worked in, and seen for that matter, would not use
horizontal antennas. They have no way of knowing what their audience
will use for antennas, and it does not make much difference as following
ionospheric reflection, all wave polarizations are available and may be
received.

At the equator, a time zone is about 1000 miles wide. at the poles (a
bad place for shortwave propagation) the width of a time zone is
insignificant. All the stations I refer to are in the temperate zone and
their targets are likely 1000 miles or so away, though some targets of
some stations are only a few hundred miles away.

Antennas at these shortwave broadcast stations are a product of studying
successful antennas and carefully designing new antennas anf testing
their performance in and around their intended targets. They are proved
to be effective.

Why would a vrtical antenna be better?

From Arnold B. Bailey`s giant antenna catalog in his "TV and Other
Receiving Antennas", the free-space gain is the same for a ground plane
as it is for a center-fed 1/2-wave dipole. An antenna`s proximity to the
earth may change the balance between horizontal and vertical antennas.

Terman writes on page 886 of his 1955 edition:
"Consider an antenna that is far enough from ground so that the total
power radiated by a given set of antenna currents is independent of the
presence of the ground. Then a ground reflection that reinforces the
main lobe will double the field strength of the main lobe, and so will
increase directive gain of the antenna system by a factor of 4. This
condition corresponds to an antenna height great enough to make the
mutual impedance between the antenna and its image small (see page
894).With horizontally polarized systems this will be the case if the
center of the antenna is at least one wavelength above ground; with
vertically polarized systems it is true even at lower heights.

However. when the antenna is sufficiently close to the ground the effect
of the ground reflection is to cause the directive gain to differ from
4. Thus , for a vertical doublet close to the ground, the directive gain
is twice the free-space value, since the presence of the ground does not
alter the directional pattern and there is no energy radiated in the
direction of the hemisphere occupied by the ground. In contrast, the
directive gain of a horizontal antenna very close to the ground can be
more than 4 as compared with the same antenna in free space, as
discussed below in connection with Fig. 23-36."

Seems horizontal antenna users are not fools after all.

Best wishes, Richard Harrison, KB5WZI

wrote:
This is an early stage of the experiment, but
I believe that there is a lot to say with the lower noise on the
horizontal antenna station


Probably has a lot to do with the particular sites
though. It's quite possible to be near a noise source
that is mainly vertical polarized. In a case like that, it's
possible it could be a problem.

Agreed.



But I never saw the difference
in noise levels you are seeing. At the worst, I might see
appx 2 S units, but sometimes it might only be one, or
even other times , nearly no difference at all. Most of
the noise I would see at this location is power line noise.

Tonight it is about 2 S units different. Also remember that I don't
have the two S-meters calibrated against each other


It seems to effect both horizontal and vertical nearly equally.
Probably cuz much is radiated by horizontal power lines.
I've never tested it, but I think if you are in a noiseless location,
the difference would be fairly small as far as meter readings
just measuring the average atmospheric noise.

I suspect so also. Maybe some day I'll test that out. The Butternut can
be removed and remounted pretty easily. There is a low noise area where
we have FD. Maybe I'll haul the vertical out there some weekend.

The reason I
say this is because sometimes I would see little difference in
noise between the two. But other times I might see more.
But you could see small differences just from the increase in
strength of dx signals. IE: if you had T-storms 1500 miles away,
it's quite likely the vertical will receive them stronger than the
horizontal due to the normal operation of the antennas.
Anyway, I don't totally consider what you see as the norm. "4 s units"
You probably have a local vertical noise source nearby. If it's power
line, etc, you might be able to track it down and get it fixed.
I'd be curious to see if you see the same 4 S unit noise difference
over a period of time. Like I say, mine would vary. But noise
never was much of a concern on mine. Never gave it much thought
at all. Kinda weird too being I'm in a big city, in a residential area.

Being mine was elevated at 36 ft at the base, I also had a pretty
good line of sight to any potential noise sources.
The tip of the radiator was at about 68 ft. As far as the VE being
better on the wire, that's probably fairly normal, being he wasn't dx.

Also, as a final note, while your butternut with 20 radials is ok, it
still
isn't quite up to the performance I saw with mine at 36 ft, using a
full size antenna. So I saw a larger signal increase on the dx than you

I bet. Mine was appx equal to a full length monopole with 60 radials,
if ground mounted. I'd have to look, but my ground may be a bit better
too. I'm right on the edge of being in a "30" zone. Of course, raising
efficiency raises s/n equally, but I noticed that I never saw the same
performance I had with the ground plane, when I ran the same full size
vertical on the ground with 32 radials. That antenna was about equal
to my dipoles at 1500 miles. Maybe a small bit better, but not any
2 S units worth like the GP was. So regardless of some saying the
number of radials is not too important, it must be, if you want the
best
performance. Sure made a difference here...

I'll be putting out more as time allows. The old back just doesn't
allow me to run more than about 5 at a time - too much Ice Hockey taking
it's toll! 8^)



Either that, or elevating it above the surroundings makes the
difference.
Myself, I think it's about 75% the first, and 25% the second...
Elevating
the antenna for sure increased my local ground wave. I could work 50
miles away ground wave easy. I'd have cases in the daytime where I'd
lose locals due to the band stretching out. But I could still nail them
at
S 9 using the GP, where the dipole would be hard to read backscatter.
Of course, if the band was open short, I'd be 10-20-30 over 9 on the
dipole
to the same location.

One thing that I am seeing is that different signals originating from
different locations are coming in at different strengths on the two
radios with the different antennas. This is fascinating. I've been
listening tonight to a VE, a Pennsylvania ham, and another from South
America.

I suppose that a lot of hams may be used to this, but I find it very
cool - I suppose that the different signals coming in at different
angles are "caught" by the different antennas differently. I gotta get
these two meters calibrated against each other.

Anyway, I guess you gotta use what works, but I don't think it's
totally
normal to see a huge difference in noise between vertical and
horizontal
unless something local is the culprit.

Could be a local problem - that one is harder for me to troubleshoot. I
would say that the noise is probably not power line source. It is a sort
of crashing noise. Almost like lightning noise, but occurring more
often, and less powerful. Could be southern hemisphere lightning storms?

- 73 de Mike KB3EIA -

Mike Coslo wrote:
. . .
I gotta get
these two meters calibrated against each other.
. . .

If you don't have a signal generator with variable output, connect the
two feedlines through a DPDT switch so it swaps the antenna to each
receiver when you switch it back and forth. Write down the meter reading
on each receiver for the same signal from the same antenna. It probably
won't take long to accumulate a decent cross reference.

Of course, you still won't have a clue as to how many dB each meter unit
represents. That'll take an investment of a few dollars and an evening
to make a step attenuator.

Roy Lewallen, W7EL

On Sat, 04 Feb 2006 03:26:46 -0800, Roy Lewallen
wrote:


represents. That'll take an investment of a few dollars and an evening
to make a step attenuator.

A greatly overlooked item of test equipment.

I recall advising a ham to buy a HP355 step attenuator so that he
could quantify the level of interference from nearby power leaks and
build a prime facie case for non compliance with emission standards.

Although he had just winged at length about his $20,000 plus
investment in a tower and VHF/UHF antennas, more on radios, etc... he
baulked at spending a $100 on something as unexciting as a step
attenuator. This was an opportunity to learn a little more about
predicting path loss than a $100 burden.

As part of my FSM project for measuring BPL emissions, I went
searching the net for kits for RF step attenuators, and all that I
found were kits that had gone obsolete, no longer available. Today it
should be a piece of cake to do a low cost kit with miniature
switches, precision surface mount resistors etc... but we as a
community are apparently not sufficiently interested in quantifying
things these days.

Owen
--

Owen Duffy wrote:
. . .
As part of my FSM project for measuring BPL emissions, I went
searching the net for kits for RF step attenuators, and all that I
found were kits that had gone obsolete, no longer available. Today it
should be a piece of cake to do a low cost kit with miniature
switches, precision surface mount resistors etc... but we as a
community are apparently not sufficiently interested in quantifying
things these days.

A step attenuator which is completely adequate for HF and can easily
resolve 1 dB can be made from a few cheap slide switches, some PC board
material, and a handful of ordinary 5% quarter watt resistors. Detailed
instructions can be found in numerous sources, including the Web -- a
Google search brought a large number of hits, the first of which was
http://www.arrl.org/tis/info/pdf/9506033.pdf. But I'm afraid that this
level of homebrewing is beyond the interest if not the ability of the
majority of today's amateurs.

Roy Lewallen, W7EL

"Owen Duffy" wrote

but we as a community are apparently not sufficiently interested
in quantifying things these days.
==========================================

"When you can measure what you are speaking about and express it in
numbers you know something about it. But when you cannot measure it,
when you cannot express it in numbers, your knowledge is of a meagre
and unsatisfactory kind. It may be the beginning of knowledge but you
have scarcely in your thoughts advanced to the state of science."

: William Thomson, Lord Kelvin, 1824-1907.
==========================================

Arithmetic is not taught in Western schools and universities any more.
Even teachers are innumerate!
----
Reg.