Measurement of the electromagnetic-radiation hazard to weapon fusing circuits

The electromagnetic-radiation hazard to weapon fusing circuits is discussed. This hazard may occur when a weapon is situated near to a transmitting aerial and is caused by induced r.f. currents in the weapon circuits. Two methods of measuring the hazard are described. The first, a bridge method, measures change in resistance of a fuse, and the second, a thermometric method, indicates rise in temperature. The main difficulty in such measurements is the possible perturbation of any induced r.f. currents owing to the presence of the measuring system. Means of overcoming this are indicated.