Impedance/frequency characteristics of some slot aerials

The ?earth-plane? measuring technique, together with a coaxial-type standing-wave indicator, was used to measure the input impedance near half-wave resonance of simple centre-fed slot aerials of various widths and of two inductively loaded (or dumb-bell type) slot aerials. The impedance characteristics of an end-fire slot aerial over an approximately 3/1 frequency range were also determined.