There's another possible option, and I haven't analyzed it but if
someone's interested it's a pretty easy process in EZNEC
Start with a 40m Moxon... on 30m use relays to switch a loading
capacitor in the reflector to get good directional properties and an
L-network at the feedpoint to match it.
I'll work it up tonight. I actually built one for 20/17m and it works well.
I also analyzed a 10/12 version and it works.
I'll check out the 40/30 version and get back to the group.
It's pretty simple if you use a boom & aluminum elements... you only
need to split and insulate the reflector too. The Moxon is already
somewhat compact on 40...
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