this post was submitted on 31 Aug 2023
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Amateur Radio
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Do you have trees? Can you run a full wave loop for 40m? (40m circuference, does not have to be of any particular shape, triangle, rectangle or what can you fit should work okayish)
Like EFHW, it gives you 10 15 20 40m, and if you load it against ground, also lower bands, perhaps also 12 and 17 with tuner (can't do that with EFHW)
This is option for base station, for portable use EFHW is your best bet
or maybe linked dipole in inverted-V configuration, fed in middle. good both for mobile and base station, but no idea how much space do you have this way
that's regular dipole, just slightly bent in middle. it's more efficient as EFHW transformer is not a bottleneck in terms of power
on a specific length you can make it work on fundamental and odd harmonics (realistically only 40-15 and 30-10 combinations) as a linked dipole. for work on other bands you'd need to reconfigure your antenna (bring it down, connect something, bring it up again)
alternatively, consider OCFD, which gets you benefits of both (4:1 transformer as used with OCFD with the same toroid size won't limit you as badly as with EFHW) https://www.qsl.net/kk4obi/OCF%20Harmonics.html depending on where you feed it, you might need to skip one band (40, 20, 15 or 40, 20, 10, but there's a way to make it work with 40, 20, 15 and 10)
both antennas are good choice for portable operation
other option is fan dipole, that is 40m, 20m and 10m connected in parallel. this is bespoke, definitely not portable antenna, but it gives you 40m, 20m, 15m (3rd harmonic of 40m) and 10m out of the box
An EFHW can be oriented as an inverted-V, it's just that it's fed at the end rather than in the middle (at the top). If that's how you set it up, the main difference is some transformer losses in the EFHW, but it can operate on all harmonics rather than just odd harmonic bands. A center fed inverted v may be a little more tolerant with regards to tuning the length. Centre-fed is going to be more "idiot proof" in that respect and possibly easier as a first antenna.
EFHW it is then, or magloop