  The charge released by impact ionization of fast dust grains impinging on
spacecraft is at the basis of a well-known technique for dust detection by wave
instruments. Since most of the impact charges are recollected by the
spacecraft, monopole antennas generally detect a much greater signal than
dipoles. This is illustrated by comparing dust signals in monopole and dipole
mode on different spacecraft and environments. It explains the weak sensitivity
of Wind/WAVES dipole antennas for dust detection, so that it is not surprising
that this instrument did not detect the interplanetary nanodust discovered by
STEREO/WAVES. We propose an interpretation of the Wind dust data, elsewhere
discussed by Malaspina et al. (2014), which explains the observed pulse
amplitude and polarity for interstellar dust impacts, as well as the
non-detection of nanodust. This proposed mechanism might be the dominant dust
detection mechanism by some wave instruments using dipole antennas.
