Sorry, meant to reply to this earlier.
Yes, that’s how it works and the tuner in the KX3 seems to cope although the changes in frequency changes the match of course. I might put the analyzer on and see what sort of mess it really looks like…
As I suspected, not pretty…
Looking across 1 to 30MHz there were two points where the setup approached resonance. One at about 6MHz (VSWR 1.29:1, RL 17.8dB, Z 50.3, R 48.6 Ohms, X -12.8 Ohms) and another at about 10MHz (VSWR 1.36:1, RL 16.4dB, Z 44 Ohms, R 42.7 Ohms) the rest was well out of range.
I think the best idea to to salvage what I can, cut the wire into ‘proper’ quarter wave lengths and add suitable elevated ground wires.
Single band antennas are probably more simple and efficient, but as you say, you have to change them to change band.
The other variable is “what you aim to achieve” from an activation. For me, at present, I like to operate for half an hour or so, maybe on more than one band, and around 20 contacts feels good - more is a bonus, fewer is a little disappointing!
I use an FT817 with an Elecraft T1, which I think is the same tuner as your KX3 has. (My favourite bit of kit, saves a lot of fiddling around, and the design just makes me smile every time I use it :o)
The antenna is either an inverted V cut approximately for 7MHz, or a piece of wire about 7.5 metres long either wound in a spiral along my 5m pole, or strung out as a sloping wire. In each case the single wire is tuned against a single random counterpoise. I have used the V on 5MHz, 7MHz, and 10MHz, and the vertical on 10MHz and 24MHz. I haven’t tried other bands with these antennas.
The purist engineer would not be satisfied with this, but I have yet to fail to qualify a summit with this arrangement. If, as many do, you want to work as much DX as possible from the summit, then antenna efficiency becomes more important.
One final thought, more to the point, rather than have different lengths of wire made up for single band ground planes, you could either use links, or shorten the wires electrically, by folding them back on themselves. You could mark the fold points with tape for each band.
73
Adrian
G4AZS
That’s an idea, I’ve done that before but forgotten about it!
I’ve just disassembled the Balun from the Pro whip, I’ll post some pictures in a minute or two so people can see what’s inside the black box…
Inside the Pro whip black box.
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