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Just Linked Dipole or multiple antennas?

As I am new in the SOTA adventure, What does everyone carry for antennas? This past weekend I used my EARCHI endfed antenna, but I am looking at building a linked dipole. The issue I see with a linked Dipole is that on popular summits (such as the one I did on saturday), there was not much room for me to be able to push up a mast and have ~60ft of wire strung up, or in an inverted V… So I’m just curious what everyone carries for different situations!

Hi Jared,
I’m sure you will get many differing answers as we all face these problems. The best antenna for a summit is the one that you have with you. That being said there are summits where there is very little space or are very busy with other visitors. (I’m presuming we are talking about HF not VHF, with these comments). For restricted summits (which I try to spot from satellite photos if its a summit I haven’t activated before) I have a tripod mounted loaded vertical antenna (Diamond RHM-8B) with an added counterpoise. In some cases an end-fed with tuner is also a possibility on a restricted summit if the ground is rocks - you can even get away with laying the antenna across the rocks (but not across soil).

If there is more room, an Inverted-V antenna (needing only one support rather than a horizontal dipole requiring two) in either linked dipole or off centre fed form will give better results than the vertical (normally). The advantage of the off centre fed is it’s multi-band capability without having to lower and raise the antenna to change bands. The advantage of a resonant linked dipole is its lighter weight as it doesn’t need the balun that the OCF does. I usually take both with me. I have the Linked dipole “band hopper” from SOTABeams (80-20m) and the UL-404 OCF from Aerial-51/Spiderbeam. If you want to build your own linked dipole antenna there is a very useful length calculator on the Sota Mapping Project webite. http://www.sotamaps.org/extras.php (click on the Linked antenna designer tab). For an OCF, there are many, many designs on the Internet to help you with this.

The rule for everyone who is starting new into SOTA is take what you have to start with. Decide only after doing a few activations what you need to change. Our biggest enemy is weight, so batteries tend to be the first to change from SLABs to LIPOs or LifePOs, then the rig, that FT-897 or 857 might seem good because it can output 100W but an FT-817 or KX-3/2 is MUCH lighter! Then the mast that you need to support the Inverted-V, most people use fishing poles rather than aluminium masts. And so it goes on …

The first thing though, is to get out there with what you have to a “simpler” summit and have fun.:grinning:
You will work out yourself what you want to change first and your solution will be different to other people (although you may adopt some of their ideas).

Have fun & welcome to SOTA activating 73 Ed DD5LP.

Jared,

I use a link dipole that has all bands 6-40 meters on it. I have tied the ends of the “inverted vee” less than a foot off the ground and it still works very well. Turns out that the dipole acts like an NVIS antenna on 40M, which is great for shorter range DX contacts, and it has no effect on 20M at all. I try and elevate the dipole higher when the shrubbery allows, but it makes very little difference in how the antenna works.

I use a 13 foot tall Crappie Pole for my mast…so I can change to most bands without lowering it at all, or by dropping it down one 3 foot section for 6/10/12 meters.

I have activated 258 summits without a miss…I have always gotten at least 10 QSO’s on every peak with this set up.

73 and good luck

Pete
WA7JTM

Jared -

See the poll on the NA SOTA reflector for an idea of what’s popular for antennas.
https://groups.yahoo.com/neo/groups/nasota/polls/poll/2791512?pollType=ENABLED&sortOrder=DESC&orderBy=DATECREATED
You’ll see the end fed half wave is very popular.

The SOTA Tuner (http://qrpkits.com/sota.html) is one way to implement an EFHW for multiple bands.

Some folks are now using trapped dipoles and EFHW antennas for ‘no tune’ solutions on multiple bands.

In space limited situations I have a ‘vertical dipole’ which is essentially a vertical with one radial. I use a 22 foot fiberglass fishing pole (not carbon fiber) to set this up for 20m and up. With the tuner in a KX3, it also does decent service on 30m.

73, Etienne-K7ATN

Normally a link dipole for 60m/40m/30m and a vertical for 30m/20m/17m/15m/12m/10m.

For special occasions I have a .64lambda 10m vertical which was used in the 6m/10m challenge and a 12m 1/4wave ground plane for the 12m challenge.

A W3EDP for 80/60/40 with a home brew tuner, and a copy of MM0FMF’s vertical for 20-10.

Brian

Just got a simple vertical vert wire of 11m strung onto a 8m telescopic pole and use the MFJ949D via a 9:1 unun h/b and four way 1/4w 40m counterpoise helps too. My first active summit and only so far as had great first contact into VK on 10w on 20m gtom G/DC-003

But rate things going here won’t be out much this year…
Be more of a chaser

But got the gear if the occasion arises

Karl

This must be some new definition of simple… :wink:

Hi Jared

A linked dipole for 6/10/20/30 and 40m. 15m is not a popular band for the east coast of Australia. Also carry a coaxial vertical for 6m and a wire J-Pole (designed by Herbert OE9HRV) for 10m. My feedline is a convenient 10m length of RG58AU.

I use telescopic fiberglass poles to support the antenna of choice. Pole lengths are 6m, 7m and 10m.

SOTA blog http://vk1nam.wordpress.com

73, Andrew VK1AD in Austria OE.

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