Helicon waves were excited by a Nagoya type III antenna in a steady st
ate argon magnetized plasma column with Dc magnetic field B-o = 400-50
0 G, electron density 10(12)-10(13) cm(-3) and neutral species pressur
e about 20 mTorr. Wavelength measurements made with B-dot probes at th
e edge of the plasma column show the presence of multimode standing he
licon waves. Azimuthal mode numbers m = +1, 0 and -1 were detected wit
h m = +1 dominant. Radial density profiles were measured with Langmuir
probes. The wavelength measurements are shown to agree with theoretic
al calculations of helicon waves in radially non-uniform plasma.