  Electric field instruments carried by spacecraft (SC) are complementary to
dedicated dust detectors by registering transient voltage perturbations caused
by impact-generated plasma. The signal waveform contains information about the
interaction between the impact-generated plasma cloud and the elements of
SC-antenna system. The variability of antenna signals from dust impacts has not
yet been systematically characterized. A set of laboratory measurements are
performed to characterize signal variations in response to SC parameters (bias
voltage and antenna configuration) and impactor parameters (impact speed and
composition). The measurements demonstrate that dipole antenna configurations
are sensitive to dust impacts and that the detected signals vary with impact
location. When dust impacts occur at low speeds, the antennas typically
register smaller amplitudes and less characteristic impact signal shapes. In
this case, impact event identification may be more challenging due to lower
signal-to-noise ratios and/or more variable waveforms shapes, indicating the
compound nature of nonfully developed impact-generated plasmas. To investigate
possible variations in the impacting materials, the measurements are carried
out using two dust samples with different mass densities: iron and aluminum. No
significant variations of the measured waveform or plasma parameters obtained
from data analysis are observed between the two materials used.
