have a few hours per night of useful recording through the ionospheric aquot;windowaquot; at 18.5 mc. ... The determination of antenna aperture requires knowledge of the antenna polar diagram and the efficiency of the reflecting surface. Our absolute measurements are being made with the simplest of antennas a dipoles a mounted over a large grid of reflecting wires. ... Comprehensive tests have been conducted to intercompare the noise power of conventional noise diodes with that ofanbsp;...
|Title||:||Annual Report of the Director|
|Author||:||Carnegie Institution of Washington. Dept. of Terrestrial Magnetism|