Does anyone know where I can find some construction plans for a "wheel
antenna" in the 33cm band?

Depends which variant you're looking for.

One "wheel" antenna type is the halo, which is basically a halfwave
dipole bent into a circle, with the ends an inch or two apart (the
distance is an important factor in the tuning), usually fed via a
gamma match. Google for "2-meter halo" (a common variety) and rescale
the design as necessary.

Another variant is the "big wheel", which is three full-wavelength
loops (each bent into a third-of-an-apple-pie shape) fed in parallel,
with a hairpin inductor shunted across the common feedpoint. Older
editions of the ARRL VHF Handbook contain plans; I don't know about
the current edition.

--
Dave Platt AE6EO
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