A Proposed Standard Dummy Antenna for Testing Aircraft-Radio Transmitters

A new type of dummy antenna employing a 35-foot roll of coaxial cable and a power indicator is described. It roughly simulates the impedance characteristics of an actual aircraft antenna, which is used over the range of 2 to 30 megacycles. Its impedance characteristics are not appreciably affected by mechanical shock, humidity, ageing, etc. Power measurements can be made with it over a wide impedance range with a single indicating instrument. The impedance presented to the transmitter terminals is unaffected by lead geometry, ammeter impedances, etc. Its power-dissipating capability is limited by the flow temperature of the cable dielectric, and is of the order of 125 watts.