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K5KGB
07-05-2009, 08:03 PM
Hey folks. I just finished homebrewing a 10m bazooka out of some extra coax. It resonates better than I had expected. I am figuring on hanging it in my attic either in a horizontal or inverted-V. Any suggestions?

I am a 10 meter fanatic simply because
1. I started in 11meter! HF working the sideband
2. I don't have a good HF rig yet.

Right now I use an HR-2510 to work 10 meters and have been using an antron 99 or IMAX-2000 and they are verticals. I have had good luck with them and I hope to have at least some luck with the Bazooka. Should I hang it in the inverted-V so it'll be somewhat of a vertical?

Thanks again.

WB2WIK
07-05-2009, 08:06 PM
If your verticals are higher up and outdoors, and you plan the bazooka to be in your attic and lower, don't expect much from the bazooka -- the verticals will work better almost always. Possibly, literally always.

It's not just the antenna design that matters, it's how it's installed and how high above ground it is.

WB2WIK/6

K5KGB
07-05-2009, 08:47 PM
The vertical I have been using isn't all that high above ground level. As I said, I hope I can get some result with this antenna. We'll see once I get the connections beefed up so I can haul it up.

WB2WIK
07-05-2009, 08:59 PM
It might work a bit, but a 10m dipole or inverted vee is a bidirectional antenna, so when it works, it will work in two directions; the vertical will work in all directions. And antennas indoors on 10m almost always don't work as well as the same antennas outdoors.

Best use of a 10m bazooka would be to attach it to a PVC, wood or bamboo pole horizontally polarized, add a boom-to-mast clamp at the center, and mount it on a mast above a rotator, outdoors. Then, you have a well-functioning rotary dipole that can be "steered" towards the station you want to work -- that helps a lot. 10m openings come from all directions, and if you have a dipole or inverted vee that's not rotatable, you miss at least half of what's actually happening on the band, because at least half the time the band will be open to where the antenna is not aimed.

WB2WIK/6

AE5TE
07-05-2009, 09:00 PM
I agree, go vertical and high.

Do let us know how it works though. Seems like one of the easiest end fed halfwaves to build (for 10M anyhow). I have a scrap piece of 9913 sitting here waiting to become such a project, but I envision slipping it into a PVC pipe and putting it on the roof to get the most out of it.

Right now everything I have is multiband &/or uses a tuner.

KA9MOT
07-05-2009, 09:08 PM
Or install it as a sloper.......will be much less directional.

WB2WIK
07-05-2009, 09:14 PM
Or install it as a sloper.......will be much less directional.

::That's true, but by doing so, you lose the three advantages of having a horizontally polarized antenna:

-Lower received noise levels
-The ability to peak desired stations and reject undesired ones
-The added antenna gain created by ground reflection ahead of the antenna

These are the reasons people use horizontal antennas to begin with. If one wants a non-directional antenna for 10m, the A99 already works pretty well and a sloping dipole is not going to work better.

WB2WIK/6

KA9MOT
07-05-2009, 09:20 PM
::That's true, but by doing so, you lose the three advantages of having a horizontally polarized antenna:

-Lower received noise levels
-The ability to peak desired stations and reject undesired ones
-The added antenna gain created by ground reflection ahead of the antenna

These are the reasons people use horizontal antennas to begin with. If one wants a non-directional antenna for 10m, the A99 already works pretty well and a sloping dipole is not going to work better.

WB2WIK/6

If you say so.

As a vertical, He won't have -The ability to peak desired stations and reject undesired ones. Have to build/buy a beam or rotatable dipole for that.

Won't always reject received noise levels (There are many times my Butternut HF-9V is quieter then my dipole.)

WB2WIK
07-05-2009, 09:26 PM
If you say so.

As a vertical, He won't have -The ability to peak desired stations and reject undesired ones. Have to build/buy a beam or rotatable dipole for that.

Won't always reject received noise levels (There are many times my Butternut HF-9V is quieter then my dipole.)

::If your Butternut is quieter than your dipole, you either have strong horizontally polarized noise generated from within your home (or very close by), or the Butternut just isn't working very well. Physics dictates exactly the opposite: A good vertical with a proper ground plane system should always receive more noise.

KA9MOT
07-05-2009, 09:35 PM
::If your Butternut is quieter than your dipole, you either have strong horizontally polarized noise generated from within your home (or very close by), or the Butternut just isn't working very well. Physics dictates exactly the opposite: A good vertical with a proper ground plane system should always receive more noise.

It works really well as is......It only has about 700 Feet of wire in the ground radial system, and worked wonderfully on Field Day with no ground radials. Maybe I need more radials............
I have no electrical type noise at my shack. On either antenna. I am just saying that SOMETIMES the Butternut is a little quieter then the dipole.

This guy was asking about using his Double Bazooka on 10M. Many of you pooh-poohed the idea.
I think it is a wonderful idea and should try if that is what you want to do. Try it, It may work...then again it may not so try it in different configurations.
Either way, if you listen to the naysayers you will learn nothing new.
Antron 99 is a good antenna as well, but it is certainly not the best.

KA9MOT
07-05-2009, 09:39 PM
Hey folks. I just finished homebrewing a 10m bazooka out of some extra coax.
Congratulations to you for homebrewing your antenna. For me, homebrewing is the most fun thing about this hobby.

K3DAV
07-06-2009, 07:18 AM
I have been working Europe, Canada, Mexico, some South America, and much of the USA on 10 meters SSB and FM with an I-MAX 2000 20 feet off the ground. On 100 watts only. The I-MAX 2000 is one hell of an antenna for 10Meters, and very quiet to boot.

The double bazooka design is a wonderful design and constructed and tuned properly, will probably beat most dipoles. But they seem to work best at lower HF frequencies like from 20 meters and below. They are at best just OK antennas at 12 meters and above. The higher up you go in frequency, a double bazooka design starts to lose it's performance reputation.

KF5BZH. You may get good use from the bazooka, but for 10 meters, your 99 or better yet, the I-MAX 2000 will most likely do a better job. And it can be used down to 17 meters with very good results. I use mine for 17 through 10 meters. On 17 and 15 meters, I have talked all over creation with great signals. And the matching network in the I-MAX 2000 helps lower all kinds of QRM. But hey, do the experimenting. That's what this hobby is about. Good luck with it, and let us all know your results.

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