Flower pot antenna maximum power!!

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OldskoolPirate
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Flower pot antenna maximum power!!

Post by OldskoolPirate » Sat Jun 18, 2022 4:42 am

Been playing around with a few flower pot antennas lately. Mostly the usual type using rg58 as the antenna itself with choke at the bottom. But how much power can this handle ? It’s super thin.

I tried making one with rg213 and I couldn’t get it anywhere near my frequency. But even 213 is thin to be using as a radiator, making the tuning so narrow.

Iv ran 100w into my rg58 antenna so far. Seemed to be ok.
:tup

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teckniqs
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Re: Flower pot antenna maximum power!!

Post by teckniqs » Sat Jun 18, 2022 10:04 am

100w is probably your limit

Albert H
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Re: Flower pot antenna maximum power!!

Post by Albert H » Sun Jun 19, 2022 4:15 am

I've made them with UR67 (much the same as RG213) and run 250 Watts without issue. Just for grins, we made a "doubled" ⅝ flowerpot out of Westflex 103. That handled over 400 Watts input, and had some useful gain, so the ERP was of the order of a Kilowatt!

Have a look at https://vk2zoi.com/articles/double-five ... lower-pot/ to see how to do it. We built ours inside white PVC plumbing pipe (don't use the grey or black - it absorbs RF!). When finished, we painted the pipe a pale grey with acrylic paint (doesn't absorb RF), so it was virtually invisible at the top of a block.
"Why is my rig humming?"
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OldskoolPirate
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Re: Flower pot antenna maximum power!!

Post by OldskoolPirate » Sun Jun 19, 2022 9:37 pm

How did you work out the length/amount of turns of the choke using rg213 ?
:tup

Albert H
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Re: Flower pot antenna maximum power!!

Post by Albert H » Sun Jun 19, 2022 9:42 pm

The first time it was trial and error - I started with 10 turns (which I found was about right for 94 MHz) At 88 MHz, I got a good match with 13 turns, and the top of the band it was 8 turns. My plastic pipe was 32mm diameter, with end caps. I cut the radiating element too short and had to add wire to the upper end of the radiator.
"Why is my rig humming?"
"Because it doesn't know the words!"
;)

Medley2k
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Re: Flower pot antenna maximum power!!

Post by Medley2k » Sun Jun 19, 2022 10:23 pm

What about using messi and paoloni ultraflex 7 or 10? Would that work and allow higher power?

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