A 2-kW electron accelerator was launched in October 1974 from the White Sands Missile Range, New Mexico, as the initial launch in the Excede series of artificial auroral experiments. The launch, designated Precede, was supported by a number of ground-based optical systems to record the electron-induced atmospheric emissions as a remote diagnostic technique of accelerator performance in addition to recording emissions of aeronomic interest in a controlled artificial aurora. The electron source, square wave modulated at 0.5 Hz, was initiated at 95 km on payload ascent and continued through apogee (120 km) to a descent altitude of approximately 80 km, providing a total of 90 pulses of the 2.5-kV 0.8-A electron beam over a period of 180 s. A rocket-borne retarding potential analyzer provided a measure of the energy distribution of electrons returning to the vehicle skin. The energy distribution of the return current electrons has been compared with laboratory measurements of the energy distribution of secondary electrons as a function of scattering angle to infer a vehicle potential due to a net positive charge buildup on the electron-emitting payload. The steady state vehicle potential at apogee is less than 30 V, with substantially smaller values determined a lower altitudes. Langmuir probe theory is shown to model accurately the altitude dependent steady state vehicle potential. Ground-based optical systems included an image-intensified spectrograph and a dual channel telephotometer recording the time dependent emission profile of the N2+(B2&Sgr;u+→X2&Sgr;g+) first negative (0-0) band at 3914 ¿ and the O(1S→1D) transiion a 5577 ¿. The spectrograph recorded emissions in the 4200- to 8500-¿ wavelength range including the prominent transitions of the N2+ first negaive, N2(B3IIg&ggr;A3&Sgr;u+) first positive and N2+ (A2IIu &ggr; X2&Sgr;g+) Meinel systems as well as the O(1S) 5577-¿ line. With the exception of the N2+ first negative system the image-intensified spectrograph indicated that these emissions are collisionally deactivated in the 80- to 110-km altitude range. The ground-based telephotometer measurements were corrected for the effects of atmospheric extinction by monitoring the apparent photon emission rates of several bright stars. An electron-induced luminous efficiency of (4.5¿0.4) ¿10-3 was determined for the N2+1 N(0--0) transition at 3914 ¿ in the 80- to 100-km altitude range.