antenna height

ground mounted vertical antenna for 11m quick over view

get a 6m pole stand it on the ground and guide rope it

run a length of 5.5m wire up the pole(half wave)

connect wire to center pin pl259 via a length of coax

connect ground to ground wires at base of pole (would suggest around 32 wires each 2.25m long) small garden 64 lengths at 1.125m long.

enjoy. and who now has a problem with planning permission

this is the basis of how a dx commander works.

please note only a quick overview will need tweaking for swr

glenn north lincs wrote:

ground mounted vertical antenna for 11m quick over view

get a 6m pole stand it on the ground and guide rope it

run a length of 5.5m wire up the pole(half wave)

connect wire to center pin pl259 via a length of coax

connect ground to ground wires at base of pole (would suggest around 32 wires each 2.25m long) small garden 64 lengths at 1.125m long.

enjoy. and who now has a problem with planning permission

this is the basis of how a dx commander works.

please note only a quick overview will need tweaking for swr

Actually, what you have built is just a simple half-wave end fed antenna.  Nothing wrong with that at all, but the DX Commander is a multi-band, multi-element vertical, some of which are quarter wave, and some bands come from harmonics of others, and hence are not quarter wave.  From memory, my DXC Lite gets 15m (with help from a tuner) from the 40m element and 10m (though not perfectly where I want it) from the 20m element, on a 7m pole.

However, I am surprised you are getting anything like a decent SWR, as that antenna should have an impedance of a few thousand ohms (As opposed a quarter wave vertical which is about 30ohms) and need a matching system of some sort.  Half wave end-feds usually use a 49:1 or similar matching transformer, but it's equally common commercially to centre feed them and get closer to the usual 70ish ohms of a dipole, with a much simpler matching network for monobanders.

The best article I found when I started building my EFHW was this one:  http://www.aa5tb.com/efha.html

Wasn't sure on the impedance so i didn't say anything but i was thinking along those lines.
It might listen but i wouldn't try transmitting.

As in not much height it seems. Ground mounting correctly designed antennas with ground plane radials, if the antenna design requires it, on 11m is a compromise 1/2, 1/4, or 5/8 waves. Through experience I have had poor results, even on E layer hops. All antennas work to a degree and in great conditions but for 11m you want some space below your feed point to improve low angle take off for DX.... in my experience. I am sure you will find models to the contrary but models are not reality.

This is only my experience so do find out for yourself.

I reckon on 6m to feed point is a good starting point.

You will do a bit of DX with a ground mount for 10/11 in good conditions. You will do more dx with an elevated antenna.

No ground mounted antenna (on good or average ground, i.e. UK mud/grass) for 10/11m has made me think this is the way to go.

10/11 is a frequency set where you can actually get height under your chosen antenna without too much hassle. As such it is a good plan to use that advantage. Whereas using lower frequencies you have to encounter much more inconvenience to get antennas high off earth relative to wavelength. (Although generalized propagation benefits can mitigate some of the downside of ground mounting for lower freqs)

glenn north lincs wrote:

ground mounted vertical antenna for 11m quick over view

get a 6m pole stand it on the ground and guide rope it

run a length of 5.5m wire up the pole(half wave)

connect wire to center pin pl259 via a length of coax

connect ground to ground wires at base of pole (would suggest around 32 wires each 2.25m long) small garden 64 lengths at 1.125m long.

enjoy. and who now has a problem with planning permission

this is the basis of how a dx commander works.

You have a problem with planning permission as does anyone who has a DX commander ground mounted in their garden. If you already have one antenna on the property which most houses do for their TV then under planning regulations any additional antennas cannot be more than 60cm in any linear direction to be able to be used without planning permission.And yes that does include wire antennas - a guy at my radio club got told to take down a wire doublet between his house and a tree because he and a neighbour had a fall out, they called planning and planning told him to remove it and apply for permission.

In regards to the pole any structure which is >3m in height needs planning.

Whether or not you get a visit depends on how many neighbours you upset.