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Looking at antennas and found this.


it looks like a standard 1/4 wave dipole. It's too easy to build for yourself. Why not save money and make your own in a few minutes?
 
dyke said:
it looks like a standard 1/4 wave dipole. It's too easy to build for yourself. Why not save money and make your own in a few minutes?
Click to expand...

I think you mean a 1/2 wave dipole. No such thing as a 1/4 wave dipole. The double bazooka uses coax cable as part of the radiating element unlike a normal dipole. Still easy to make as long as you waterproof the cable and joints really well. they work about as good as any other decent dipole, maybe slightly better,

doublebaz.GIF
 
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Lots of 'stories' going around about 'bazooka' antennas. They are basically a 1/2 wave dipole with a different method of being fed. It's been around since the 1930's - 1940's, first used as a radar antenna by the military. Most of the 'stories' about them are more myth than fact.
The 'biggy' for most people is that they tend to have a fairly constant SWR over a wide range of frequencies. What that does say is that their efficiency drops the further away from the design frequency you use it. SWR stays about the same, but efficiency drops. That's because of the way the thing is fed, each 'side' is a tuned circuit, almost like a gamma match, sort of. That 'tuned circuit' tends to add reactance as it moves away from it's design frequency so that an SWR meter tends to stay in a 'better' reading longer. The bad part about that is that reactance doesn't radiate anything so that what get's radiated tends to decrease as reactance is increased.
There's also a myth about it's power handling ability. It actually has less power handling ability than a comparable dipole made from the same sized conductor as the bazooka's center conductor. There's nothing 'magic' about it, but they do work.
If you can find one of the early ARRL 'Antenna Compendium' books there's a very interesting study done about them. Several different feeding methods, and other changes done with a bazooka antenna, and how the measurements for them are arrived at. And then there are the mechanical draw backs to consider. Since coax is used, they are heavier than a 'regular' wire dipole.
Wanna try one? Do so! They really do work as well as a 'normal' dipole. Just don't think that you've got some kind of 'miracle' worker, they aren't.
- 'Doc
 
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That little extra matching inefficiency gives you the added false sense of wider bandwidth.

Also, depending on how stout it is built will determine it's survivability in the horizontal position. They'll play just as well and survive longer if mounted as an inverted V.

I would only erect one over a standard traditional dipole if I found one, or was given one. I certainly wouldn't build one and I would only use it long enough to be replaced by a regular "dipole".
 
Another interesting factoid most people overlook is that the Bazooka is also a resonant closed loop, which helps decrease harmonic radiation & noise.

Performance-wise, I'd prefer a Double Extended Zep, 5/8 per side, so you get a bit of gain, but the pattern isn't as symmetrical as a standard 1/2 wave dipole, and the impedance is about 150Ω so you have to feed it with a 1/4 wave of 75Ω, using the 75Ω VF x 9'.

Why not try a 2.75:1 rectangular quad element? It's almost omni, with gain and less noise-prone than a dipole, plus I hear it's about a 50Ω load so you can direct feed it like a dipole.

Should be around 13' 6"H x 60"W (depending on the VF of the wire) for vertical, fed at the center of a long(?) side, or 90° (on it's side) for horizontal.

Copper-clad will probably need the 1005/freq in mhz for approximating size.

Homer, didn't you play with one of these? If not, someone I heard on L38 did, and was liking his home-brewed version.
 
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I am getting up for work and having coffee, WOW thanks for taking the time for posting great answers to my question. I have more reading to do! I know there is no " Magic " or " Quiet " antenna And I still want to make or buy a wire antenna that works. Out of all the wire antennas what is the best to put up. A simple dipole, Balun or no balun. and configeration, Inverted V . I can buy a simple dipole with a 1:1 balun for about 35.00. And that would be easy for me to screw coax to and conect. CBradiomagazine did a nice test on a wire antenna as well.
Thanks for all the help and your input. " wire antennas always seem like a mystery to me!
 
I have a Workman BS-1 dipole I bought years ago I believe they are about $20.00 shipped the are 18 foot total length and I now Ive ran my HF rigs through mine so it will take 100 watts forsure. I talked skip on 25 or 30 watts. I am really curious what they will actually take for power I will have to experiment with one since nobody else has.

http://www.cbradios4you.com/servlet/the-571/Workman-BS-dsh-1-CB-Radio/Detail
 
Needle Bender said:
Why not try a 2.75:1 rectangular quad element? It's almost omni, with gain and less noise-prone than a dipole, plus I hear it's about a 50Ω load so you can direct feed it like a dipole.

Should be around 13' 6"H x 60"W (depending on the VF of the wire) for vertical, fed at the center of a long(?) side, or 90° (on it's side) for horizontal.

Copper-clad will probably need the 1005/freq in mhz for approximating size.

Homer, didn't you play with one of these? If not, someone I heard on L38 did, and was liking his home-brewed version.
Click to expand...
I have a rectangle in the attic. It is 12' x 6' roughly. I feed it with twin lead\4:1 balun\75 OHm 1/4 section then coax jumper to the antenna switch. I did not feed it with coax to check the 50 Ohm impedance direct match. i have talked around town, and some DX with it. Currently it just lets me listen to the Amateur bands from time-to-time.
 
TonyV225 said:
I have a Workman BS-1 dipole I bought years ago I believe they are about $20.00 shipped the are 18 foot total length and I now Ive ran my HF rigs through mine so it will take 100 watts forsure. I talked skip on 25 or 30 watts. I am really curious what they will actually take for power I will have to experiment with one since nobody else has.

Workman BS-1 CB Radio Dipole Antenna
Click to expand...


If it is a regular wire dipole it will take TONS of power. It is limited only by the size of the wire. Typical 14 gauge wire will take THOUSANDS of watts and then some.;)
 
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I did a double extended Zepp, and it worked very well. Have since gone to a Homer built end fed 1/2 wave just because it was easier for me to hang.

Dipoles are super easy to make and tune, and so is the double bazooka. Lots of posts on this forum about this topic!

73,
RT307
 
Im actually in need of a 160 meter dipoole so thats my next project maybe next month Ill do it or atleast get it done before spring spring time.
 

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