Personnel protection from electrocution through whip antennas

A device for personnel protection from electrocution through whip antennas is described. It is a high-pass filter implemented as a nonlinear capacitor possessing a falling capacitance-voltage characteristic installed in the middle part of the antenna. This filter presents low impedance to a high-frequency signal. To line-frequency voltage of up to 33 kV, the filter is a high impedance, limiting the current through the human body to 4-5 mA. This current is felt, but results neither in muscle contraction nor heart fibrillation. Short-term (up to several seconds) AC voltage withstanding capabilities of many capacitor types were investigated in a wide temperature range. The encapsulated capacitor fits easily between the antenna links. The flashover behavior of polluted skirted insulators made of different dielectrics with several types of coatings was studied at dry, wet and ice conditions. Experiments were made before and after environmental and field tests. Even under simulated heavy salt rain, there was no flashover of the 13 cm-long insulator at the test voltage of 24 kV rms. Field tests showed that the protection device can operate in extreme service conditions and is abuse-proof. Protected antennas were tested at an antenna range in the VHF diapason (30-88 MHz). Practically no impairment of the antenna RF quality was detected.