White light seen at 10:30 pm traveling from NW to SE at very high rate of speed.Slows momentarily to beam down conical light, then resumes course

My wife and I were camping 4 1/2 miles east of Taft, CA while attending a model airplane meet. Weather was calm, clear, temperature very mild, moon- less sky & dark except for lights of Taft and Bakersfield (30 miles away).  While sitting in front of our trailer enjoying the serenity of the Spring evening at approx. 10:30 pm, I noticed a white light approaching from the NW in the direction of Taft Airport.  The light was fairly un- spectacular in appearance, not nearly as bright as an aircraft landing light and rather indistinct. The light, however, kept my attention due to its very high speed and relatively low altitude of approx. 5,000 ft. Once the light was directly over the town of Taft it began to slow down considerably to what I would say was a normal lightplane cruising speed. At that moment, the object "blinked" on an enormous conical shaped beam of yellowish light straight down. The beam at its widest & lowest point was at least five times the size of the object itself.  I grabbed a pair of 8x50 binoculars out of my flight box and observed the object and the beam for only a very few seconds. The object was a very hazy, indistinct ball of white light with no apparent anti-collision or navigation lights like an airplane.  The beam was very well defined against the night sky and did not reach the hill tops below it. As quickly as the beam "blinked" on it turned off and the object started to accelerate very rapidly as it resumed its southeasterly course paralleling the Diablo Range & heading over the Tehachapis towards Los Angeles. My wife saw the object too, and remained fairly unimpressed by the spectacle, dismissing it as nothing more than an experimental military aircraft from Edwards AFB.  The craft followed the same course as the airliners that were flying high above it since this is on the main flight corridor between L.A. and the S.F. Bay Area following the Coast Range. The object was in sight approx. 15 seconds and made no sound even though it travelled at jet fighter-like speed.