Hi-Gain Vertical Half Wave Antenna

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shuffy
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Re: Hi-Gain Vertical Half Wave Antenna

Post by shuffy » Sat Jun 21, 2025 1:08 pm

Yeah I remember the comment and I'm sure it will stop it melting.
My current configuration is a split air cored coil as per the original higher powered NRG, so the former material is not an issue. I think my coils are 18 SWG wire so that might need beefing up a bit.
He said shuffy! I said WOT? Woo!

jvok
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Re: Hi-Gain Vertical Half Wave Antenna

Post by jvok » Sat Jun 21, 2025 1:17 pm

Are there build instructions for the air cored one?

Gigahertz
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Re: Hi-Gain Vertical Half Wave Antenna

Post by Gigahertz » Sat Jun 21, 2025 1:54 pm

jvok wrote: Sat Jun 21, 2025 1:17 pm Are there build instructions for the air cored one?
Yes Lee posted them on this topic, think its the 2nd or 3rd page that takes you to a drop box

Frequent Lee
no manz can test innit
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Re: Hi-Gain Vertical Half Wave Antenna

Post by Frequent Lee » Tue Jun 24, 2025 4:30 am

Gigahertz wrote: Sat Jun 21, 2025 12:28 am A year after my first attempt, I finally had time to try the top end of the band.
The very early NRG verticals I bought from Stephen used to come with a cut down 2L fizzy pop bottle as a rain shield, I'd forgotten about that until you posted these pictures.

When he transitioned across to the plastic funnels he said he has to make a trade off with the length vs the weather protection, the longer bottle fully covered the feed point and coli components whereas the funnel only about a 1/4 of it & the longer angled funnel was to make water run off at a steeper angle, when the bottle version was used 24/7 the enclosed space of the bottle caused heat build up and would throw the matching out enough to trigger the swr protection in some rigs not built by him, ie the London ones. I guess the heat would make things expand and contract with the copper coils which are super sensitive to the matching circuit.

Frequent Lee
no manz can test innit
no manz can test innit
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Re: Hi-Gain Vertical Half Wave Antenna

Post by Frequent Lee » Tue Jun 24, 2025 4:34 am

I do have a couple of brand new unused ones of the 50w version one is tuned to 88.1 and the other 94.6.

If anyone wants to make an offer one one we can sort something out.

I'm keeping one for that inevitable bank holiday weekend pop up pirate appearances maybe 😋😜

Gigahertz
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Re: Hi-Gain Vertical Half Wave Antenna

Post by Gigahertz » Wed Jun 25, 2025 11:55 pm

Frequent Lee wrote: Tue Jun 24, 2025 4:34 am I do have a couple of brand new unused ones of the 50w version one is tuned to 88.1 and the other 94.6.

If anyone wants to make an offer one one we can sort something out.

I'm keeping one for that inevitable bank holiday weekend pop up pirate appearances maybe 😋😜

Hmmm, tempted, just to have the original version as a reference point, but I'm sure others will bite your hand off!

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