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.

100w is probably your limit

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.

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

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.

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