Metal detector sensor device

 Sensors for this device may be different, depending on the purpose for which it is collected. To search for metal fragments in the walls is the most convenient to use the PIN from the transformer iron section 20 x 20 and 300 mm long. Frames are made for him, such as hardboard. The coil formers are coiled coil. Frames should move freely on the rod. Adjustment of phase coil shall be so installed that, in the absence of metal near the headphones could be heard almost no sound. The frames are fixed firmly on the Web with glue. All three contain the same number of turns of the coil-250. MOTAT them maximally accurately to L2 and L3 are absolutely identical, as far as possible. Coil L1 is disqualification from 20 revolution. If a generation is not stable, it has washed away try to make withdrawal from the larger number of turns.

With the coil L1 is worth the experiment. To increase the sensitivity of the device from the Electrolytic Capacitor, transistor collectors you can connect the generator to the top not found, and the additional allotment of fewer coils, counting from the bottom. This should be reduced in proportion to the number of turns until the bottom drain. The capacitor (C) still leave connected to the top-the conclusion. Such a change would increase the sensitivity of the scheme, but will lead to increased energy consumption from the power source.

I made this with a mass of coil taps and connected to different, achieving the best performance.

Diameter of wire windings of the generator is not critical. However, the thicker the wire, the smaller windings ohmic resistance, less heat loss, less consumption of energy from the batteries. So, the battery will last longer. I use wire 0.2. Rx coils can overlap quite a thin wire.

For easy retrieval of the metal in the grass and ground my buddy has made the original sensor. Is described from the metal rod placed into the bottom of the hollow bamboo canes. The device placed in the hilt. Wire between sensor and device used shielded, missed their inside canes. Used in-ear headphones from your music player. Their invisible wire is to the canes through the sleeve. Using this tool, you can search for lost items without drawing attention to himself.