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That'll never work!

I thought it might be interesting to share an experience from the recent trip to Cornwall which illustrated rather well that it’s always worth giving an idea a go; ignore conventional wisdom and just do it.

 

As part of the aerial arrangements for the 'try to work the Bouvet DXpedition adventure' I wanted to have some capability for 80m.  Normally a vertical is the way to go but I wasn’t equipped for that so the only simple solution was a dipole.  Now the theory says that a dipole needs to be at least a half wave above ground to have any kind of useful radiation pattern.  The lower it is, the higher the angle of take-off and on a band like 80m a low dipole would be pretty much an NVIS antenna, more commonly known as a cloud burner with most of the energy going straight up and useless for DX.

 

Well a half wave at 80m is of course 40m and on the coast in Cornwall there are no trees that high, in fact there are no trees. All I had was the club mast which was at half height due to the 40+ mph winds. This put the centre (the 1:1 balun) of my dipole hanging below the Spiderbeam at about 6m above ground.  That left the problem of what to do with each end of the dipole.  In the end I used the longest pieces of string I could find, attached them to the end of the wire and anchored the string ends to stakes in the ground resulting in the ends of the wire elements being about 1.5m above ground making this dipole an inverted V. Hopeless. Never mind the clouds; this was going to burn grass.

 


Low-slung dipole

Picture 1: The low-slung dipole highlighted


 

So just how bad was it? When I arrived in Cornwall I had worked 47 countries on 80m from home on my 40m Off-Centre Fed Dipole (that’s not supposed to work either) and it had taken three years.  At the end of the trip I had worked 102 countries on the band including ZL2OK on 80m SSB with a report of 55 both ways.


 

QSL from New Zealand

Picture 2: QSL from New Zealand


So, never mind the theory, just do it. It’s amazing what a few pieces of wire can achieve on HF. If you fancy a bit of long distance DX but think you don’t have room for an HF beam, just throw a length of wire out of a window or up a tree.  You’ll be amazed at what it can do and doubly amazed when you put FT8 into the equation.


73


Chris G8AJM


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