Magnetic-field pickup for low-frequency radio-interference measuring sets

A magnetic-field pickup has been developed utilizing the Hall effect in intermetallic semiconductors. Unlike a loop pickup, the sensor responds to magnetic flux density and thus is independent of frequency. Due to its extremely small size, it makes possible the measurement of magnetic fields in constricted regions. When used in conjunction with ferrite flux collectors, its sensitivity is 10
^-7
gauss in the range of 30 cps to 15 kc. Details of design and construction are given.