The BAZOOKA Antenna

[sinus trouble]

Yes it worked first time, No adjustments needed!

Also as it was a quick test the location was not ideal! I will do some more testing and post any findings!

I doubt it would handle more than 25 Watt? Lets push it and see if it goes up in smoke!

[Albert H]

I've been running 600 Watts into a twin ⅞ Flowerpot without any hassle. The antenna is inside a PVC pipe, and raised 14m above the water tower that it's on. It radiates remarkably well for an aerial that cost about 30 Euros to knock out!

[radium98]

History man

[mpx]

Interesting stuff Albert, would you post details or a diagram of that?

[sinus trouble]

Wow!! 600 is good going Albert!! Didnt expect that

I did read that some had handling powers of 100W easily with RG58U (Which is what i used) But that may not be a continuous rating?

Once a thorough test has been carried out, I do plan to tidy it up for a more robust use!

[Albert H]

I've got a commercial aerial back at home that's similar to the Flowerpot, and it uses H100 coax and is rated at a Kilowatt.

Drawing of the twin FP aerial tomorrow when I get back.

[sinus trouble]

Another update!

I made up a simple bracket to test the Flower pot antenna outdoors which worked great!

However for the antenna, I measured the dimensions for 98Mhz (Mid Band) Tests were performed using a transmitter that can sweep the band easily!

Depending on the accuracy of my measurements? I found the antenna resonated nicely around the 101Mhz mark? Which would indicate that the dimensions are slightly on the short side?

Coverage around my area seemed solid despite the low elevation!

I was pretty impressed at the performance!

FP ANT.jpg

[radium98]

Bravo Sinus...
is there any progress with the STL ?

[sinus trouble]

Bravo Sinus...
is there any progress with the STL ?

Thank you Radium

It is by far the cheapest antenna to build and it performs just as good as a dipole!

I have not found any problems with the STL so i doubt i will make any changes?

[Polecat]

Another update!

I made up a simple bracket to test the Flower pot antenna outdoors which worked great!

However for the antenna, I measured the dimensions for 98Mhz (Mid Band) Tests were performed using a transmitter that can sweep the band easily!

Depending on the accuracy of my measurements? I found the antenna resonated nicely around the 101Mhz mark? Which would indicate that the dimensions are slightly on the short side?

Coverage around my area seemed solid despite the low elevation!

I was pretty impressed at the performance!

FP ANT.jpg

Hi ST. Been a while. The Bazooka looks great and sounds like a lot less hassle than the roll up slim jim. Well done!

[mpx]

Looks nice, discreet too. Might have a go at making one of these

[sinus trouble]

Hi ST. Been a while. The Bazooka looks great and sounds like a lot less hassle than the roll up slim jim. Well done!
[/quote]

Hello Polecat

Hope you are doing well? Im glad we are back to some sort of freedom now!

Anyways yes it seems the Balun/Choke is critical to keeping this type of antenna stable!

I run an RG213 patch lead up to the antenna which works well, Once bang on frequency i will heat shrink the coax in place to keep it weather and insect proof!

[sinus trouble]

Looks nice, discreet too. Might have a go at making one of these

Cheers geez!

Defo worth a try! You could even tape it to maybe a broom stick or something similar? Although PVC pipe is so cheap, lightweight and easy to trim!

Again, I do like dipoles, but i get alsorts of wildlife nesting in the tubes!

[radium98]

A must respect for you ST

[EFIALTISFM]

Look for the "Flowerpot Antenna" It's easier than the "simple" Bazooka to get going:

http://vk2zoi.com/articles/half-wave-flower-pot/

Albert is right... a simple build compared to other antenni inc dipoles.
Built in under 1 hr.
Tested with 4Watt board, meter shows "a tad under" 4W with SWR 1.2:1. Not bad at all.
Build for 98Mhz but trying it on 106 right now and its looking good.

Thanks Albert

Here is a photo on the rooftop... bit windy!!!
https://ibb.co/Sr8yDGL

[Albert H]

I made one recently for a friend, and used white 32mm PVC pipe. It took a bit of tweaking, but inside 40 minutes, I had a resonant aerial, with a couple of dB gain over a dipole, that withstood a 45 mph wind without flexing. It shows a 1.03 : 1 match at its designed frequency. It was built using RG58, and works really well at 50 Watts. The whole thing including the coil was painted with pale grey acrylic paint, so it's really difficult to see against the sky!

This has got to be just about the cheapest way to build a useful aerial. The PVC pipe and end caps came from a local DIY shop and cost about £9. I was posh, and used a rubber grommet for the lead coming out of the bottom cap. The aerial is about 30mm longer than it needs to be (at the bottom end) and this allows it to clamp to an aluminium mast easily. If I go by the site in the next few days, I'll post a photo.

[sharky]

Just before I stopped radio altogether, I had a bazooka and a dipole stacked.
Bazooka was 1.2 @ 50watts and the dipole ( with a series match ) was at 1.1, when I stacked them it went to 1.7 and I couldn't figure out why.
I went through 3 harnesses and the best I got was 1.4, I hit 17 miles with a blank carrier.
Just wished I'd used it sooner tbh.

Fantastic to see everyone is still brainstorming.

[sharky]

I should mention, the bazookas lower element was copper pipe and not left with just the braid. RG58 and 15mm copper pipe in a 22mm white polypipe.
Insulating tape at the bottom of the copper element to hold it in place. I think the picture may be on my photobucket somewhere.

[Albert H]

I used to build them out of microbore plumbing pipe for the upper radiator, and 12mm copper pipe for the quarter wave sleeve. The gap at the feedpoint was well wrapped with self-amalgamating tape, and the whole mess fitted into a white 22mm PVC pipe with end caps. I added about 40cm to the bottom part of the poly pipe to give something to anchor the mast to..... The copper pipe inside the PVC pipe prevented it from bending in the wind. It was painted with acrylic paint to make it inconspicuous. We used lots of these over the years, and the DTI / RA or whoever seldom found them - they were looking for shiny aluminium aerials! In some cases we put them right at the top of a communal mast up a block, and they'd look like just an unused part of the mast.....

[radium98]

Albert H , one question , did you everthink to make in youre age a history book ? for rf and what you did in youre life ?....nothing then history to post ....