Development of UHF spark-switched L-C oscillators

We have constructed L-C oscillators (LCOs) with center frequencies of 450 MHz up to 800 MHz. The Q of these oscillators varies from 6 to 8 for the 450 MHz device, down to 1 to 2 for the 800 MHz unit. Q is increased when a resonant antenna or antenna-reflector combination is added. Prototypes with simple fat-dipole antennas and small parabolic reflectors (8" x 20") have radiated normalized electric field strengths of 60 kV/m at 1 meter (measured in far-field and extrapolated back to 1 meter).