Is It double bazooka less noisy?

[lu6etj]

Dear friends

It is usually said (in my country) that the double bazooka antenna is
less noisy than a standard dipole.
I think that there are not good reasons that endorse such a statement
for noises coming from the far field (maybe it has some advantage with
near field noises or maybe because its frequency response cures some
pitfails of the associated receiver).

I have looked for information in the net about this topica but I have
not been lucky.

I suppose that you have treated this topic at some time. If you can
point me to a link to read about I would be very grateful to you.

Also if you can give me your opinion in this respect.

Thank you very much in advance

Miguel (LU 6ETJ)

[w***@akorn.net]

Post by lu6etj
Dear friends
It is usually said (in my country) that the double bazooka antenna is
less noisy than a standard dipole.
I think that there are not good reasons that endorse such a statement
for noises coming from the far field (maybe it has some advantage with
near field noises or maybe because its frequency response cures some
pitfails of the associated receiver).

I tested an IAC double bazooka, and it is no different than a regular
dipole. It has very slightly less signal level, and very slightly more
bandwidth. Not enough to worry about. No measurable difference in
noise.

73 Tom

[H. Adam Stevens, NQ5H]

Post by w***@akorn.net

Post by lu6etj
Dear friends
It is usually said (in my country) that the double bazooka antenna is
less noisy than a standard dipole.
I think that there are not good reasons that endorse such a statement
for noises coming from the far field (maybe it has some advantage with
near field noises or maybe because its frequency response cures some
pitfails of the associated receiver).

I tested an IAC double bazooka, and it is no different than a regular
dipole. It has very slightly less signal level, and very slightly more
bandwidth. Not enough to worry about. No measurable difference in
noise.
73 Tom

We beat bazookas to death here years ago.
Don't waste your time.

73
H.
NQ5H

[lu6etj]

Dear friends:

Thank you very much for your answers.

First of all: I agree with you, but my agreement is inductive, not
experimental because I have not made my homework with that antenna...
.
I knew the excellent article of Walter Maxwell, I am a fan of Maxwell,
(both Maxwells) from their famous article "Another look on reflections"

But do I think: is it possible that all those friends that are
enthusiastic of the bazooka are affirming foolishness? They say: -With
the bazooka we listen stations that we don't with the plain dipole, and
this affirmatiotn point to a better SNR...

I think that it must have something true behind so many similar
statements. In the radio club of my area they say to have compared one
against another with clearly favorable results to the bazooka.

I thought...: A plain dipole is not a monoband antenna, it is, in fact,
a multiband antenna, it receives all the frequencies. But do let us
imagine a plain dipole that had connected on its terminals a couple
high Q tuned circuits. That system it would be really "monoband"...
then, if we connect such a system to a poor receiver Would not it
improve the reception perhaps?, eliminating by that way possible
saturation sources or intermodulación noises.
Such a system, empirically it would seem a practically "more silent
antenna" and it would explain, perhaps, the some results obtained by
the colleagues. I say this because it is said that the bazooka
possesses a syntony effect that transforms it into a true monoband
device (I am not sure of it).

It is only an arbitrary example of possible alternative explanations
that, without violating the fundamental principles, can be
compatibilized with the experiences of so many colleagues that
sympathize with this antennas(some of which deserve my technical
respect).

I thank all your answers but I continue to the search of some
explanation that endorses all the facts, just as the formidable article
of Walter in reference to its bandwidth...

I am for sure some of you will be able to help me to find a convincing
explanation.

Thank you very much in adavnce

Miguel Ghezzi (LU 6ETJ)

[H. Adam Stevens, NQ5H]

Miguel
There are "eyewitness accounts" of all sorts of foolishness.

If you build it perfectly a bazooka will show a decrease in SWR over a very
small range either side of resonance (SWR = 1:1) when compared to a dipole.
This is completely useless except as an academic exercise.

Here's how it works:
The antenna is a parallel-resonant network (the bazooka) in parallel with a
series-resonant network(the dipole).
The parallel resonant (tank circuit) network stores energy and will
oscillate at it's DRIVEN frequency when driven near resonance, so it stores
the energy that would otherwise be reflected as long as it oscillates. Go
too far from resonance and it quits oscillating. This effect manifests
itself at SWR of 1.2:1 or lower. It flattens the SWR curve very near
resonance.
The 2:1 bandwidth is unaffected except by the additional loss of the tank
circuit sitting across the dipole feed point.

What Walter Maxwell showed explicitly is that any increase in SWR bandwidth
is entirely due to loss, if I recall correctly.

So all the trouble of building a bazooka with both legs and the dipole
resonant at exactly the same frequency is a waste of time.
A simple dipole works a bit better and is *MUCH LESS* work and expen$e.

73
H.
NQ5H


"lu6etj" <***@gmail.com> wrote in message news:***@s13g2000cwa.googlegroups.com...

Dear friends:

Thank you very much for your answers.

First of all: I agree with you, but my agreement is inductive, not
experimental because I have not made my homework with that antenna...
.
I knew the excellent article of Walter Maxwell, I am a fan of Maxwell,
(both Maxwells) from their famous article "Another look on reflections"

But do I think: is it possible that all those friends that are
enthusiastic of the bazooka are affirming foolishness? They say: -With
the bazooka we listen stations that we don't with the plain dipole, and
this affirmatiotn point to a better SNR...

I think that it must have something true behind so many similar
statements. In the radio club of my area they say to have compared one
against another with clearly favorable results to the bazooka.

I thought...: A plain dipole is not a monoband antenna, it is, in fact,
a multiband antenna, it receives all the frequencies. But do let us
imagine a plain dipole that had connected on its terminals a couple
high Q tuned circuits. That system it would be really "monoband"...
then, if we connect such a system to a poor receiver Would not it
improve the reception perhaps?, eliminating by that way possible
saturation sources or intermodulación noises.
Such a system, empirically it would seem a practically "more silent
antenna" and it would explain, perhaps, the some results obtained by
the colleagues. I say this because it is said that the bazooka
possesses a syntony effect that transforms it into a true monoband
device (I am not sure of it).

It is only an arbitrary example of possible alternative explanations
that, without violating the fundamental principles, can be
compatibilized with the experiences of so many colleagues that
sympathize with this antennas(some of which deserve my technical
respect).

I thank all your answers but I continue to the search of some
explanation that endorses all the facts, just as the formidable article
of Walter in reference to its bandwidth...

I am for sure some of you will be able to help me to find a convincing
explanation.

Thank you very much in adavnce

Miguel Ghezzi (LU 6ETJ)

[Ian White GM3SEK]

Post by lu6etj
I knew the excellent article of Walter Maxwell, I am a fan of Maxwell,
(both Maxwells) from their famous article "Another look on reflections"

"Their" article? Walt has a ghost writer?

[H. Adam Stevens, NQ5H]

I think he's referring to the Maxwell of Maxwell's Equations.

Post by Ian White GM3SEK

Post by lu6etj
I knew the excellent article of Walter Maxwell, I am a fan of Maxwell,
(both Maxwells) from their famous article "Another look on reflections"

"Their" article? Walt has a ghost writer?
--
73 from Ian GM3SEK

[Cecil Moore]

Post by Ian White GM3SEK

Post by lu6etj
I knew the excellent article of Walter Maxwell, I am a fan of Maxwell,
(both Maxwells) from their famous article "Another look on reflections"

"Their" article? Walt has a ghost writer?

Post by lu6etj
I knew the excellent article of Walter Maxwell, I am a
fan of Maxwell, (both Maxwells) from their famous article
"Another look on reflections"

[Ian White GM3SEK]

Post by Ian White GM3SEK

Post by lu6etj
I knew the excellent article of Walter Maxwell, I am a fan of
Maxwell, (both Maxwells) from their famous article "Another look on
reflections"

"Their" article? Walt has a ghost writer?

Post by lu6etj
I knew the excellent article of Walter Maxwell, I am a
fan of Maxwell, (both Maxwells) from their famous article
"Another look on reflections"

You're right, Cecil - my apologies to all concerned.

[Tom Donaly]

Post by Ian White GM3SEK

Post by lu6etj
I knew the excellent article of Walter Maxwell, I am a fan of Maxwell,
(both Maxwells) from their famous article "Another look on reflections"

"Their" article? Walt has a ghost writer?

It's the royal "their."
73,
Tom Donaly, KA6RUH

[lu6etj]

Hi Hi...

Don't forget I am argentine, here we speak spanish all the day, it is
my own translation error of possesive case... "their" it is wrong ,
"his" is the correct.-> "...from HIS famous article..." R?

References to "both" Mawells, yes, James an Walter..., (thanks Adam)

Miguel
-----------------------

Post by Tom Donaly

Post by Ian White GM3SEK

Post by lu6etj
I knew the excellent article of Walter Maxwell, I am a fan of Maxwell,
(both Maxwells) from their famous article "Another look on reflections"

"Their" article? Walt has a ghost writer?

It's the royal "their."
73,
Tom Donaly, KA6RUH

[Cecil Moore]

Post by lu6etj
Don't forget I am argentine, here we speak spanish all the day, it is
my own translation error of possesive case... "their" it is wrong ,
"his" is the correct.-> "...from HIS famous article..." R?

The negative comments occurred because of errors in
the attribution of your posting. It wasn't your fault
so please don't worry about it.

Back to Double Bazookas: It is a well accepted fact that
insulation reduces the precipitation static problem.
So the Double Bazooka reduces the precipitation static
in two ways. 1. DC path between elements, 2. Insulation.

[w***@akorn.net]

I A B tested a regular low dipole made from number 8 AWG bare wire
against a double bazooka. Even during severe weather there never was a
difference in measureable noise levels.

That's just from a direct observation over a long period of time
between the two antenna types.

There also was no measurable or noticeable difference in signal
strength or bandwidth.

73 Tom

[Cecil Moore]

Post by w***@akorn.net
I A B tested a regular low dipole made from number 8 AWG bare wire
against a double bazooka. Even during severe weather there never was a
difference in measureable noise levels.

Did you A B test them under precipitation static conditions?
If not, the test was incomplete. There is obviously a charged
particle difference between a bare wire dipole and a double
bazooka. If you weren't testing using charged particles, the
test was just as obviously incomplete.

[Jim Kelley]

Post by Cecil Moore

Post by w***@akorn.net
I A B tested a regular low dipole made from number 8 AWG bare wire
against a double bazooka. Even during severe weather there never was a
difference in measureable noise levels.

Did you A B test them under precipitation static conditions?
If not, the test was incomplete. There is obviously a charged
particle difference between a bare wire dipole and a double
bazooka. If you weren't testing using charged particles, the
test was just as obviously incomplete.

Cecil,

There is absolutely no reason to believe that one antenna is less
responsive to charged particle noise than the other. Whether or not
the antenna can accumulate a static charge is a separate issue.

73, ac6xg

[Cecil Moore]

Post by Jim Kelley
There is absolutely no reason to believe that one antenna is less
responsive to charged particle noise than the other.

What about all the web references that say precipitation
static can be decreased by insulating the antenna from
the charged particles in the air?

Think about it. A charged particle hitting a bare wire
will likely transfer a charge. A charged particle hitting
an insulated wire may or may not transfer a charge depending
upon the insulation.

After all, air is an insulator. A charged particle missing
the antenna entirely is in contact with that air insulator.

[H. Adam Stevens, NQ5H]

Post by Cecil Moore

Post by Jim Kelley
There is absolutely no reason to believe that one antenna is less
responsive to charged particle noise than the other.

What about all the web references that say precipitation
static can be decreased by insulating the antenna from
the charged particles in the air?
Think about it. A charged particle hitting a bare wire
will likely transfer a charge. A charged particle hitting
an insulated wire may or may not transfer a charge depending
upon the insulation.
After all, air is an insulator. A charged particle missing
the antenna entirely is in contact with that air insulator.
--
73, Cecil http://www.qsl.net/w5dxp

I once had a ladder line fed doublet.
It was disconnected at the feedthroughs because a thunderstorm was about ten
miles North.
I could pull 1 inch arcs off the feedthroughs to a grounded wire.
Made me think of Ben Franklin.

73
H.
NQ5H

[Tom Donaly]

Post by H. Adam Stevens, NQ5H

Post by Cecil Moore

Post by Jim Kelley
There is absolutely no reason to believe that one antenna is less
responsive to charged particle noise than the other.

What about all the web references that say precipitation
static can be decreased by insulating the antenna from
the charged particles in the air?
Think about it. A charged particle hitting a bare wire
will likely transfer a charge. A charged particle hitting
an insulated wire may or may not transfer a charge depending
upon the insulation.
After all, air is an insulator. A charged particle missing
the antenna entirely is in contact with that air insulator.
--
73, Cecil http://www.qsl.net/w5dxp

I once had a ladder line fed doublet.
It was disconnected at the feedthroughs because a thunderstorm was about ten
miles North.
I could pull 1 inch arcs off the feedthroughs to a grounded wire.
Made me think of Ben Franklin.
73
H.
NQ5H

A man could get killed fooling with that kind of stuff. It's a wonder
Ben lived as long as he did.
73,
Tom Donaly, KA6RUH

[Jim Kelley]

Post by Cecil Moore

Post by Jim Kelley
There is absolutely no reason to believe that one antenna is less
responsive to charged particle noise than the other.

What about all the web references that say precipitation
static can be decreased by insulating the antenna from
the charged particles in the air?

I refuse to take responsibility for the things other people say. :-)

Post by Cecil Moore
Think about it. A charged particle hitting a bare wire
will likely transfer a charge. A charged particle hitting
an insulated wire may or may not transfer a charge depending
upon the insulation.

Consider the nature of dielectric materials. I could be wrong, but I
bet if you stuck a negative oxygen ion on the outside of a jacketed
conductor, you could make the conductor inside think you had put an
electron directly on it.

Post by Cecil Moore
After all, air is an insulator. A charged particle missing
the antenna entirely is in contact with that air insulator.

And air, which is an insulator, is also in contact with a bare wire
antenna - presumably 'insulating' it. The difference is one of
density (and dielectric constant).

I suppose if you set up a big electric or magnetic field in the proper
orientation, you could make a lot of the ions go away from an antenna.
But controlling plasmas is kinda like herding cats.

73, ac6xg

[H. Adam Stevens, NQ5H]

Post by Jim Kelley

Post by Cecil Moore

Post by Jim Kelley
There is absolutely no reason to believe that one antenna is less
responsive to charged particle noise than the other.

What about all the web references that say precipitation
static can be decreased by insulating the antenna from
the charged particles in the air?

I refuse to take responsibility for the things other people say. :-)

Post by Cecil Moore
Think about it. A charged particle hitting a bare wire
will likely transfer a charge. A charged particle hitting
an insulated wire may or may not transfer a charge depending
upon the insulation.

Consider the nature of dielectric materials. I could be wrong, but I bet
if you stuck a negative oxygen ion on the outside of a jacketed conductor,
you could make the conductor inside think you had put an electron directly
on it.

Post by Cecil Moore
After all, air is an insulator. A charged particle missing
the antenna entirely is in contact with that air insulator.

And air, which is an insulator, is also in contact with a bare wire
antenna - presumably 'insulating' it. The difference is one of density
(and dielectric constant).
I suppose if you set up a big electric or magnetic field in the proper
orientation, you could make a lot of the ions go away from an antenna. But
controlling plasmas is kinda like herding cats.
73, ac6xg

My first physics job was in fusion.
Herding cats is trivial.
73
H.
NQ5H

PS I like my SteppIR.
Now THAT's broadband and insulated.

[Cecil Moore]

Post by Jim Kelley
Consider the nature of dielectric materials. I could be wrong, but I
bet if you stuck a negative oxygen ion on the outside of a jacketed
conductor, you could make the conductor inside think you had put an
electron directly on it.

The question is whether the electron stays on the insulation
or migrates through it to the conductor.

The size of the charge Vs the dielectric determines how
much of the charge actually reaches the conductor. When
I went from bare wire to 600v insulation, my precipitation
static problems decreased considerably. Then when I went to
1000v insulation and a full wave loop, most of my precipitation
static problems disappeared.

The worst case of precipitation static seems to be for
airplane antennas. Insulation is the recommended cure
although folding is also mentioned. Please do a web
search for "precipitation static" and see for yourself.

http://www.atis.org/tg2k/_precipitation_static.html

[Jim Kelley]

Post by Cecil Moore

Post by Jim Kelley
Consider the nature of dielectric materials. I could be wrong, but I
bet if you stuck a negative oxygen ion on the outside of a jacketed
conductor, you could make the conductor inside think you had put an
electron directly on it.

The question is whether the electron stays on the insulation
or migrates through it to the conductor.

Actually, the question is whether or not one can hear the resulting
noise.

Post by Cecil Moore
The size of the charge Vs the dielectric determines how
much of the charge actually reaches the conductor.

Perhaps you mean the amount of charge Vs. the dielectric determine the
voltage.

Post by Cecil Moore
When
I went from bare wire to 600v insulation, my precipitation
static problems decreased considerably. Then when I went to
1000v insulation and a full wave loop, most of my precipitation
static problems disappeared.

I see your point. The poorer the dielectric and the greater it's
thickness, the lower the induced voltage. There should be some
effect, yes. What'd you use, 20 meters of CRT anode wire or spark
plug wire? :-) The point with which Tom seemed to take issue was the
implication that an antenna with low DC resistance would have lower
precipitation static noise. I also disagree with that notion.

Post by Cecil Moore
The worst case of precipitation static seems to be for
airplane antennas. Insulation is the recommended cure
although folding is also mentioned. Please do a web
search for "precipitation static" and see for yourself.
http://www.atis.org/tg2k/_precipitation_static.html

I'm glad we agree on the definitions. In one of your previous
references I noted the term precipitation static used (incorrectly) to
describe the noise associated with static discharge. This is a
distinction I attempted to point out in my earlier post.
Precipitation, among other things, can cause charge to accumulate on
objects which are insulated from ground. This accumulation can
continue to increase until breakdown occurs, causing a spark and a
noise which is big enough to knock down the receiver AGC for a few
seconds (or worse). Precipitation static is the noise which is
apparent when a relatively high flux of ions impinges upon an antenna.
Low DC impedance antennas won't accumulate large amounts of charge
or generate a static discharge, but they are nevertheless sensitive to
the static noise just as any other antenna would be. In other words,
you and Tom W8JI are both right - you just don't know why. ;-)

Did you see the article in Harper's magazine on W6AM? Pretty neat.
Even that article mentioned precipitation static.

73, ac6xg

[Cecil Moore]

Post by Jim Kelley

Post by Cecil Moore
The size of the charge Vs the dielectric determines how
much of the charge actually reaches the conductor.

Perhaps you mean the amount of charge Vs. the dielectric determine the
voltage.

size = amount = magnitude = amplitude. It is hard to visualize
how a charge could make it to the conductor without the migration
of a quantum particle.

Post by Jim Kelley
The point with which Tom seemed to take issue was the implication
that an antenna with low DC resistance would have lower precipitation
static noise. I also disagree with that notion.

Both of you misunderstood the definition of "noise" that I was
using. With the feedline completely disconnected from the
transceiver, arcing occurred and that aural noise woke me up at
night. It was aural noise from the arcing caused by precipitation
static charge tansfer that woke me up and a low DC resistance
eliminated it.

Post by Jim Kelley
Precipitation
static is the noise which is apparent when a relatively high flux of
ions impinges upon an antenna. Low DC impedance antennas won't
accumulate large amounts of charge or generate a static discharge, but
they are nevertheless sensitive to the static noise just as any other
antenna would be. In other words, you and Tom W8JI are both right - you
just don't know why. ;-)

When a charge hits a closed loop, there are two paths it can take
to equalize the charge around the loop. Only one of those paths
is through the receiver and that is a higher impedance path than
the other path. When a single-wire dipole needs to equalize the
charges between the dipole elements, there is only one path available
- through the receiver which often has a capacitor in series and thus
blocks DC charge equalization. This is, of course, not the only reason
that a loop is quieter than a single-wire dipole but is simply one of
the reasons.

Incidentally, "Quietflex" antenna wire, with its 1000v insulation
reduced the problem to an acceptable level in the Arizona desert.
I still use that wire for my dipoles.

[w***@akorn.net]

For the past few days we had rain and lighting. Prior to any rain
hitting my antennas the steeady background noise hissing came up.

The noise came up first on my high dipoles, two regular dipoles at
150-160 feet. One was bare #14 copperweld, the other is insulated #10.
they were both equal as near as I could tell.

It came up the same but later in time on my three low 80 meter dipole
antennas at about the same rate. Two were bare wire and one was a
coaxial double bazooka. All are at about 35-40 feet high.

I have a 1/4 wl shorted stub I use as a second harmonic trap on 80
meters. It switches in and out with a relay on an RCS-8V switch that
selects trunk lines to antennas. I pulled the relay wire off, and the
80 meter dipoles had then same steady noise as with the stub in. The dc
path had no effect at all on steady noise, but on the high dipoles,
both the insulated one and bare one, there was a popping noise about
once every second or two that went away with the dipoles center
conductor grounded. I could hear this popping noise on any antenna near
the dipoles.

I added a 470K resistor to the 80M feedlines and the popping noise
quit. I removed it and added a choke and the popping noise quit. When
lightning would hit the popping noise would quit for a while, and then
come back.

As the storm got worse the noise got worse. When the rain was very
heavy and lightning very close, I stopped for a while. At that point
the noise was terrible on all antennas, but definately worse in level
on the high antennas. It was no better and no worse on any antenna at
the same height.

All through this my IAC double bazooka was no quieter than a regular
dipole made from #16 bare copper located 100 feet away at the same
height.

This test was with all antennas in place at the same time on the same
day in the same weather.

73 Tom

[Cecil Moore]

Post by w***@akorn.net
All through this my IAC double bazooka was no quieter than a regular
dipole made from #16 bare copper located 100 feet away at the same
height.
This test was with all antennas in place at the same time on the same
day in the same weather.

Precipitation static doesn't always occur during thunderstorms.
It's effects are greatly reduced in high humidity environments.
For precipitation static to occur requires charged particles.
And you don't know if charged particles even existed during
your experiment. To separate charged particle effects from
lightning effects you need to run your experiment without
the clouds and thunderstorms under conditions that guarantee
charged particles. That would be during a dust storm on a clear
sky day under low humidity conditions as often exist in Queen
Creek, AZ.

Precipitation static is a large problem for airplanes but
only when they are flying through a field of charged particles.
One of the treatments for precipitation static on airplane
antennas is to insulate the antenna inside a non-conductive
pipe. Another treatment is to fold the antenna. These are
well known, well accepted methods of reducing precipitation
static problems on airplane antennas. You can verify those
facts for yourself through a little web research.

[Gene Fuller]

Post by Cecil Moore
Precipitation static doesn't always occur during thunderstorms.
It's effects are greatly reduced in high humidity environments.
For precipitation static to occur requires charged particles.
And you don't know if charged particles even existed during
your experiment. To separate charged particle effects from
lightning effects you need to run your experiment without
the clouds and thunderstorms under conditions that guarantee
charged particles. That would be during a dust storm on a clear
sky day under low humidity conditions as often exist in Queen
Creek, AZ.

Cecil,

This is close to being an all-time RRAA classic.

Precipitation, at least in the form of rain, often occurs when the
humidity is quite high.

Do you suppose they should have named it dust storm static rather than
precipitation static? Or perhaps dry rain static?

8-)

73,
Gene
W4SZ

[Cecil Moore]

Post by Gene Fuller
Precipitation, at least in the form of rain, often occurs when the
humidity is quite high.

Yes, and triboelectric charging is known to be magnitudes
worse in low humidity conditions. On this web page:

http://www.esda.org/basics/part1.cfm

it says that a worker at a bench can expect 6000v when the
relative humidity is 10-25% Vs 100v when the relative humidity
is 65-90%.

Post by Gene Fuller
Do you suppose they should have named it dust storm static rather than
precipitation static? Or perhaps dry rain static?

"Charged particle" static would have been more descriptive
since "precipitation" is most associated with falling H2O.

If the relative humidity is 10% when the rain starts falling,
seems the precipitation static would be worse than if the
relative humidity was 90% when the rain started falling.

Dry snow falling in low relative humidity conditions could
certainly carry large charges. Dry wind driven dust particles
in low relative humidity conditions are often associated with
precipitation static.

But assuming that raindrops falling in high humidity conditions
are electrically charged is a questionable assumption. And trying
to detect precipitation static noise in the presence of lightning
seems like looking for a needle in a haystack.

It is good engineering practice to try to isolate what one is
trying to measure. The best way I know of to isolate precipitation
static from other noise sources is to perform the measurements
under clear sky, windy, low humidity conditions in the desert.

I strongly suspect that w8ji didn't detect any of the arcing
noise in the double bazooka that he detected in the bare wire
ungrounded dipoles. Was that a noise reduction?

[Cecil Moore]

... but on the high dipoles,
both the insulated one and bare one, there was a popping noise about
once every second or two that went away with the dipoles center
conductor grounded.
All through this my IAC double bazooka was no quieter than a regular
dipole made from #16 bare copper located 100 feet away at the same
height.

I forgot to ask. Did the double bazooka arc like the
ungrounded dipoles?

[H. Adam Stevens, NQ5H]

This is hilarious.
No matter in what context, it appears bazookas cause long threads.

73
H., NQ5H

[Cecil Moore]

Post by H. Adam Stevens, NQ5H
This is hilarious.
No matter in what context, it appears bazookas cause long threads.

I don't remember the bazooka ever being discussed before
in the context of precipitation static so it is essentially
a brand new topic.

[H. Adam Stevens, NQ5H]

Actually, I recall your mentioning it before, Cecil.
But I'll be damned if I'll go search threads from near half a decade ago to
prove it.
Brand new topic or not, it involves bazookas.
Cheers
H.
NQ5H

Post by Cecil Moore

Post by H. Adam Stevens, NQ5H
This is hilarious.
No matter in what context, it appears bazookas cause long threads.

I don't remember the bazooka ever being discussed before
in the context of precipitation static so it is essentially
a brand new topic.
--
73, Cecil http://www.qsl.net/w5dxp

[Cecil Moore]

Post by H. Adam Stevens, NQ5H

Post by Cecil Moore
I don't remember the bazooka ever being discussed before
in the context of precipitation static so it is essentially
a brand new topic.

Actually, I recall your mentioning it before, Cecil.

Couldn't be. I didn't know what the schematic was for
a double bazooka until I looked it up last week. The
double bazooka uses the same techniques that are used
on airplanes to reduce precipitation static.

[Cecil Moore]

Post by H. Adam Stevens, NQ5H
I once had a ladder line fed doublet.
It was disconnected at the feedthroughs because a thunderstorm was about ten
miles North.
I could pull 1 inch arcs off the feedthroughs to a grounded wire.
Made me think of Ben Franklin.

For sure, a gradient is established by thunderstorms
resulting in all sorts of electrical and magnetic
phenomena. But the particular type of noise I am
talking about is precipitation static caused by
charged particles hitting a bare wire dipole when
one element of the dipole is floating. In particular,
this type of noise can occur in the Arizona desert
when there is not a cloud in the sky. Here is how
"precipitation static" is defined:

http://www.atis.org/tg2k/_precipitation_static.html

"ATIS is a United States based body that is committed to
rapidly developing and promoting technical and operations
standards for the communications and related information
technologies industry worldwide using a pragmatic, flexible
and open approach. ATIS is accredited by the American National
Standards Institute (ANSI)."

[Cecil Moore]

Post by lu6etj
But do I think: is it possible that all those friends that are
enthusiastic of the bazooka are affirming foolishness? They say: -With
the bazooka we listen stations that we don't with the plain dipole, and
this affirmatiotn point to a better SNR...

The Double Bazooka is probably quieter than a plain dipole
because, unlike a plain dipole, there is a DC path between
all points in the antenna thus minimizing the effects of
precipitation static.

[H. Adam Stevens, NQ5H]

Post by Cecil Moore

Post by lu6etj
But do I think: is it possible that all those friends that are
enthusiastic of the bazooka are affirming foolishness? They say: -With
the bazooka we listen stations that we don't with the plain dipole, and
this affirmatiotn point to a better SNR...

The Double Bazooka is probably quieter than a plain dipole
because, unlike a plain dipole, there is a DC path between
all points in the antenna thus minimizing the effects of
precipitation static.
--
73, Cecil http://www.qsl.net/w5dxp

So a nice 2.5 K ohm resistor at the feed point of a dipole would be vastly
less work.




"With

Post by Cecil Moore

Post by lu6etj
the bazooka we listen stations that we don't with the plain dipole"

I doubt anyone can document that.

[Cecil Moore]

Post by H. Adam Stevens, NQ5H

Post by Cecil Moore
The Double Bazooka is probably quieter than a plain dipole
because, unlike a plain dipole, there is a DC path between
all points in the antenna thus minimizing the effects of
precipitation static.

So a nice 2.5 K ohm resistor at the feed point of a dipole would be vastly
less work.

Yes, it has nothing to do with SWR or bandwidth. I reduced
the precipitation static problem in the Arizona desert by
going to a full wave 40m loop, the one on my web page.

[lu6etj]

Thanks Cecil

I haven't experience with the antenna, a colleague suggest possibilitie
in a RC meeting, but fans of bazooka insisted on "all wheather quieter"
(in addition, on various internet selling sites bazooka it is offered
being "less noisy").

I think if this was the case would be enough to install on plain dipole
a RF ckoke or standard trifilar balun + a ckoke to ground on de rig.
what do you think about?

I have seen very well documented measurements about claims about "EH
Antennas" (my predilect Roswell alien antenna :>)), but i haven't find
anything similar about "silents bazookas" :>(

Here, there are many "hard to die" myths, and I can´'t deal alone with
all of them, hi hi. SWR related are the mains but antenna gain specific
myths run "elbow to elbow"

73's

Miguel LU 6ETJ
www.solred.com.ar/lu6etj

[Cecil Moore]

Post by lu6etj
I think if this was the case would be enough to install on plain dipole
a RF ckoke or standard trifilar balun + a ckoke to ground on de rig.
what do you think about?

I would like to see the noise comparisons among a Double
Bazooka, a plain dipole, and a folded dipole. My Arizona
desert precipitation problem certainly decreased when
I went from a G5RV to a full-wave 40m loop.

With the G5RV, one element was grounded through the coax
shield and the other element was capacitor isolated from
ground by a series cap in my transceiver. It arced at the
coax connector and a choke did solve the arcing problem.

[lu6etj]

Here in Buenos Aires (near de Atlantic Ocean and the River Plate) it is
a very humid area, our typical old wives phrase for all the illness is
"lo que mata es la humedad" (what kills you is the humidity) ;>)

(R to Adam I don't see your 2k5 answer, and R also to your doubts about
a documented quieter performance, well, I am just searching for a
documented falsehood of these extended claims, hi hi)

Another antenna very reputed here as "quieter" it is a simple
triangular loop, similar to Cecil's example, maybe the static
explanation is OK.
But... very few days at the year we have low humidity climate. (I never
have burn a FET o MOS IC by touch them in my 38 years of continuated
activity in electronics, but, yes, I kill various equipments by invert
its polarity :>) )

Do you think that static precipitation it is a valid explanation in
these conditions?

cheers

Miguel

[w***@akorn.net]

Post by lu6etj
Do you think that static precipitation it is a valid explanation in
these conditions?

No. It makes no difference at all.

If you have a static build-up problem all you need do is install a leak
resistance or a suitable RF choke to ground. One should have that in an
antenna anyway.

I have the choice of any antenna I want and unlimited space to install
them. I often have several antenna types up for any one band at the
very same time. I've had a coaxial dipole up along with another dipole
the same height, and there is no noticeable difference in any aspect of
performance. I've even removed the shorted wire connection (the center
conductor connection past the feedpoint) and restored it, and the
antenna performance remains virtually identical in both noise and
bandwidth.

73 Tom

[Cecil Moore]

Post by w***@akorn.net

Post by lu6etj
Do you think that static precipitation it is a valid explanation in
these conditions?

No. It makes no difference at all.

It certainly made a difference in the Arizona desert under
conditions that cause precipitation static in a dipole with
no DC path between the elements. Many hams have direct
experience and have reported it. Here is a discussion of
such over on eHam.net.

http://www.eham.net/forums/Elmers/83174?ehamsid=87e9956f8473775c84a978db4ce15751

Post by w***@akorn.net
If you have a static build-up problem all you need do is install a leak
resistance or a suitable RF choke to ground. One should have that in an
antenna anyway.

But a lot of hams don't know that and run their dipoles with
the two coax conductors DC isolated from each other. I'll bet
the "plain dipoles" being described by lu6etj as noisy don't
have a leak resistance. The Double Bazooka is automatically
protected from static buildup between the elements as are loops,
and folded dipoles.

[Cecil Moore]

Post by w***@akorn.net
I've even removed the shorted wire connection (the center
conductor connection past the feedpoint) and restored it, and the
antenna performance remains virtually identical in both noise and
bandwidth.

If these tests were not performed under precipitation static
conditions, they obviously wouldn't show any difference.

[Cecil Moore]

Post by lu6etj
I have looked for information in the net about this topica but I have
not been lucky.

Try http://www.w2du.com/r2ch18.pdf Being lossy reduces the
noise but not the signal to noise ratio.