A vertically pointing Doppler radar was installed approximately 50 meters from an instrumented platform where lightning is constrained to strike and where the lightning current is recorded. The experiments were designed to study the effect of lightning on the surrounding precipitation but no discernable disturbance of the precipitation particle velocity or radar reflectivity was ever detected in any of the 39 radar observed events. However, well-defined Doppler spectra attributed to transient lightning channel echoes were occasionally observed. These data suggest that a sustained lightning continuing current is required to allow a persistent radar return from the channel and, therefore, the observation of a well-defined Doppler spectrum. The sidebands observed in the lightning Doppler spectrum can be interpreted in terms of a modulation of the radar echo associated with the time variations of the continuing current noticeable in the recordings.