Triangle will work fine.
160m probably not; it's a bit short. It would help if you included a
relay opposite the feedpoint to open it on 160m.
I've read of people using an L/C resonant trap instead of a relay, for
just this purpose. The trap opens the loop on the lowest band, and
appears as a capacitive reactance in series with the loop on the
higher-frequency bands.
--
Dave Platt AE6EO
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