One wire

If you go out portable with a radio, the ability to multiband easily and quickly is often quite an important feature for an antenna.

All my work to date has been with elevated monoband verticals, using two elevated radials.  These are, of course, extremely good antennas, cheap and easy to build and very robust.

But the radials, spanning a diameter of 10m at 14MHz, can present a trip hazard when there are a lot of people around.  Dogs also tend to walk into them, getting very confused!  Even though I have public liability insurance via EURAO, we all have to do what we reasonably can to reduce the chances of causing injury.

No radials!  At IO73rj today.

So, I got out one of my 9:1 end-fed antennas, which I bought many years ago from EARCHI.  It's the most simple antenna you can imagine, bottom fed, and needs any random length wire that isn't a half wave on any band you want to use it for.

Using a 10m pole at the beach is not easy for two reasons: (1) there are no easily-available screw-in bases for them and (2) they are very much more prone to wind than a 7m pole.

Accordingly, I limited my coastal experiment this afternoon to a 7m pole and a plastic ground screw used for rotary clothes lines.  The wire was therefore limited to about 6m.

I found this length of wire matched up easily with the internal rig ATU (Kenwood TS480SAT), on all bands 40-6m.

After about an hour of 14MHz WSPR listening, I found a median enhancement at the coast with this antenna of+6.3dB, with a range of +2dB to +14dB.  Allowing for a 2-3dB advantage in favour of the slightly inland delta I was comparing with, this comes out at a true like-for-like advantage of about 10dB.  The best enhancements were for long-haul DX (VE7AHT (+10.5db) and AE7YQ (+14dB)).

Whilst the end-fed is likely to be a few dB weaker than a monoband elevated vertical with radials, it offers performance not too different to such an antenna, with the three big advantages of being multiband, not requiring radials, and of short length.

(Thanks to AI3V, who asserts in a typical 'Trumpian' fashion that enhancements from the coast are "BS".  But not to worry,  QRZ.com swung into action to defend a white old Republican under an attack of his own making, and deleted the thread when, after repeated requests to explain why that is so, he could do no more than submit increasing levels of idiocy.)