There are different types of metal detectors and different ways of working depending on the design and use desired. Here is a brief picture of some type of metal detector:

Metal detector VLF (Very Low Frequency): This detector uses very low frequency signals (VLF) to detect metal objects. It is transmitted through the Litz wire wafting (coil) and when it touches metal objects, it experiences fluctuations that can be detected by detectors. These detectors are relatively cost-effective and are good at detecting metal objects in the ground.

Metal detector PI (Pulse Induction): This detector uses high voltage pulses to generate magnetic fields that are then used to detect metal objects in the soil. The range of this detector is usually better than VLF, but the sensitivity of the average VLF is a little less than the VE.

Metal detector BFO (Beat Frequency Oscillation): This detector uses two parts of the coil that are oscillating to detect metal objects. One part of the coil produces signals, and the other detects changes in signals caused by the presence of metal around the coil. The detector is relatively simple and cost-effective, but not as many as the other type of metal detector.

Metal detector TR (Transmit-Receive): This detector uses transmission coils to generate signals and the receiver coils to detect changes in signals caused by metal. This detector is more sensitive than the BFO detector and is good for detecting small metal objects and is located on the surface.

Metal detector MF (Multi-Frequency): This detector uses several frequencies to detect metal objects. This MD is more sensitive than a single frequency detector and is good at detecting different kinds of metal and gold objects. This detector signal is more stable than any other detector signal and can find different types of gold in the soil. This multi-frequency device also works well in high-land mineralization environments because in Indonesia, the average mineralization is recommended.

Zero Voltage Transmissionl detector (ZVT):It's a metal detector that uses a specific oscillator sequence to generate signals. It is transmitted through the coil of wire litz and when it touches the metal object, it experiences fluctuations that detectors can detect.

One of the key features of ZVT technology is its ability to produce high voltage pulses in the transmission section without using any voltage.

The metal detector ZVT is GPZ7000 It's known for its depth and its ability to detect large metal objects in very deep, so there's already a lot of large gold nuggets found with these detectors, and they're often used by treasure seekers and archaeologists to find embedded metal objects.

Altogether, ZVT technology is a state-of-the-art metal detection system and has significantly increased the performance and efficiency of metal detectors.

The kind of metal detector that suits you depends on your specific needs and what you're looking for is detected.