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Emp Analysis Of An Fm Communications Radio With A Long Wire Antenna, George H. Baker Iii, Werner J. Stark
Emp Analysis Of An Fm Communications Radio With A Long Wire Antenna, George H. Baker Iii, Werner J. Stark
George H Baker
A Norton equivalent circuit is developed for a long-wire antenna used with a VHF man-pack FM radio exposed to an incident electromagnetic pulse (EMP). The required short-circuit current and antenna impedance are computed by use of a transmission-line model for the antenna, and the computations are compared with measurements of the short-circuit current and antenna impedance. The comparison shows that the transmission-line model for the antenna is adequate for performing a vulnerability analysis of the radio. A network model is developed for a portion of the radio and is used as the load in the Norton equivalent circuit. Load currents …
Radar Observations Of Two Dimensional Turbulencein The Equatorial Electrojet, 3. Nighttime Observations Of Type I Waves, D. T. Farley, Bela G. Fejer, B. B. Balsley
Radar Observations Of Two Dimensional Turbulencein The Equatorial Electrojet, 3. Nighttime Observations Of Type I Waves, D. T. Farley, Bela G. Fejer, B. B. Balsley
Bela G. Fejer
The large vertically directed 50-MHz radar at Jicamarca has sufficient sensitivity to study nighttime echoes from the equatorial electrojet in detail with good resolution. Here we concentrate on type 1 (‘two-stream’) echoes. We find that (1) these echoes sometimes dominate the spectrum (which is never the case in daytime for a vertically directed radar), (2) they are observed over a much wider range of altitudes than they are during daytime, (3) they show an asymmetry which reverses from day to night (downgoing waves are more common at night), (4) the magnitude of the mean Doppler shift appears to increase somewhat …
Direct Observation Of Pulsed Third Sound Mass Displacement Waves In Unsaturated Superfluid 4he Films, Robert Hallock, J. S. Brooks, F. M. Ellis
Direct Observation Of Pulsed Third Sound Mass Displacement Waves In Unsaturated Superfluid 4he Films, Robert Hallock, J. S. Brooks, F. M. Ellis
Robert Hallock
We report direct observation of pulsed third-sound film thickness oscillations in unsaturated superfluid 4He films using a capacitance technique. Simultaneous measurements of accompanying temperature oscillations allow the first study of the relative amplitudes of these oscillations and the results are in reasonable agreement with the theory of Bergman although some discrepancies are noted.