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Quiz of the day 3 - Make an antenna out of this.

This is the summit shelter on Mount Blair GM/ES-035. It has a fancy viewpoint indicator capping the stone walls.

Now, the question is, how can this be made into an antenna?

73, Fraser

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Everything can be antena. But I think, this not because you need to drill holes for connections. And that is destroying of the property. Maybe even some kind of monument

But, it is good ground for mag mount antenna :slight_smile:

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Could you put a vertical antenna and use the gap to create a beam? Something like the image below where the antenna would be where all the rays cross. Might only be useful for UHF and there was a listener in line with the gap. It looks a bit heavy to rotate. :slight_smile:

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Nice loop antenna :grinning_face_with_smiling_eyes:

Are those screws holding the plates? Unscrew one on the right and one on the left of the entrance and attach a wire with a banana plug to each. (If there are no screws, clamp the wire to the edge or tape it) Plug the two connectors into the banana to BNC adapter on the antenna connector of the KX2 and let the tuner do its work. :sweat_smile:

Armin

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Hi Fraser,

Here you can make a big loop with only 2 holes (for the big CV) :joy:

3m diameter will work on 160m but not sure of parasite capacitance… :rofl:
Tks Armin idea

73 Éric

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Really if you can ensure the continuity of the metal surface between the top of the “C” and the bottom of the “C” with an ohmmeter why not try :wink:
You need a coupling loop which remains motionless during your tests! So it will take you a long time !!! We might as well take advantage of the beauty of the site and use its (or these) antenna (s) duly tuned for our Hobby !

:wink: Éric

It’s stainless steel by the looks and that is an awful conductor of elastictrickery. If you want a simple antenna on Mount Blair, throw a wire up on to one of the masts up there.

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Oui un bon plan de sol :+1:

My initial thought was “mmm… Loop?” Then I read further, and Eric F5JKK has already got my idea!

I agree, not a good idea. :grinning:
But a ground for another antenna is another good idea.

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Possible ground plane for a VHF or UHF mag mount antenna. Note: A lot of stainless steel is magnetic.
Bar clamps in lieu of holes, good solid connection. Clamps can be plastic, so insulators, but they can pin wire, strapping, foil, etc to the open ring.
Gamma match a horizontal loop. Can’t tell the diameter, maybe an 80m or 160m magnetic loop?

Can anyone say: RF burns?

73, Bruce

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There’s a square tower up there festooned with microwave dishes and mobile phone masts. I felt it would be best avoided. I set up down the southern slope on soft heather out of the breeze and away from the brain cookers. :wink:

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Well Fraser, I’m late. However I’m sure undoing screws or drilling into the metal would be against the Spirit of SOTA and probably illegal. Being on a pile of rock it’s not going to be a great radiator. Being stainless steel it’s probably not magnetic.

If you were desperate the outside circumference could be loop coupled to without interfering with the view of function of the ring. Some duct tape would hold the link in place. It would not affect the use as a visitor guide or even be noticed by them.

With a good tuner you could probably get resonance on 20 m or 30 m and secure 4 contacts on CW. The efficiency might not support SSB.

A project for those with time to spare.

73
Ron
VK3AFW

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I thought of using it as a DDRR loop but connecting to it would be the issue with the high current required.

So the backup suggestion is to mount a camera tripod on it with a vhf antenna on that. It’s nicely elevated for that task.

Andrew vk1da

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Yes. The biggest RF field is probably from cellphone antennas. But there may be RF noisy equipment in the huts, like AC systems and power supplies.

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I suppose the microwave dishes are very tight beam compared the the cell antennae. I managed a couple of 2m QSOs on the yaesu ft3d handheld into Edinburgh without issue too…

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