[UPDATED, COMPLETED VERSION OF THIS ANTENNA PROJECT DETAILED HERE.]
Well the sun is shining in Wales, but the wind is still a bit strong at 35mph gusts today.
I like the 30m band, but don't do enough operating there. So I wanted to see if I could use a standard, nominally 7m fishing pole, to suspend a 5m long wire so that it would work as a 30m vertical with a loosely-calculated, detachable coil at the base, and as a 20m vertical without the coil.
10MHz bottom-loaded vertical, flapping in the wind... |
Well, even though the coil was a bit of a guess, and I only have one radial for getting a rough idea if it would work at all, I already get a 1.25:1 match. A standard 1/4 wave vertical has a native SWR of 1.3:1, so this is working well.
The coil itself is loosely wound on a 38mm diameter, ~170mm long PVC drain pipe section, 1.3mm enamelled copper of 13 turns. Matching done using a SARK analyser and spreading/compressing the coil until best match achieved.
First test of the coil. It worked! Wire can later be taped or glued in place with silicone sealant, etc. |
I'm currently sending 200mW WSPR, with very good early results, considerably better than anyone else I can find on the database in the UK on the 10m band running 200mW. So this antenna can be made to a higher standard, have another 1/4 wave radial added, and deploy at the beach from the end of next week onwards, where travel to anywhere in Wales will be permitted.
My 200mW, vs. 5W from G0IDE. |
Spots of 200mW, 16:26-17:26UT 16/03/2021. |
Despite using 14dB more power than I am, my all-distances result is only 7dB weaker than G0IDE. |
At DX distances, my 200mW is only 2dB down on 5W from G0IDE, though more data is needed. |
Against what is probably a dipole (operators are extremely poor at corresponding or providing info about their antennas), my short 30m vertical is doing very well. |
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