The frequency of a metal detector is one of the main characteristics that determines how well targets can be detected. Generally, a single frequency detector that transmits at a high frequency will be more sensitive to small targets and a single frequency detector that transmits at low frequencies will give more depth on large targets. Minelab’s single frequency technologies are VLF and VFLEX. Minelab’s revolutionary BBS, FBS and MPS technologies transmit multiple frequencies and are therefore simultaneously sensitive to small and deep large targets.
The frequency that a metal detector operates at (transmitted by the search coil) affects its performance, as a rule of thumb, the lower the frequency, the deeper it can penetrate the ground. At low frequencies however, sensitivity to small low conductive targets is reduced. The higher the frequency, the higher the sensitivity to small targets, but will not penetrate as deeply.
In general, gold detectors operate at higher frequencies (to find small nuggets), while coin and treasure detectors work at lower frequencies for deeper penetration. The exception to this is MPStype metal detectors that are sensitive and deep seeking simultaneously.