The walk through metal detector manufacturer tells you that the metal detector (underground metal detector) circuit has no adjustment part except the sensitivity adjustment potentiometer. As long as the welding is correct, the circuit can work normally. When the whole machine is static, that is, when the speaker does not make sound, the total current is about 10mA. When the sound of the metal speaker is detected, the current of the whole machine rises to 20mA. A new laminated battery can work for 20-30 hours.
If the newly welded metal detector (underground metal detector) cannot work normally, the walk through metal detector manufacturer tells you to first check whether the components on the circuit board and the wiring are soldered correctly, and then measure whether the battery voltage and power supply circuit are normal. The stable voltage of Zener diode VD1 is between 5.5 and 6.5V, and the polarity of VD2 should not be reversed. Do not weld the primary, secondary and the first and last ends of the oscillating coil in the detection dish wrongly.
The manufacturer of the walk through metal detector tells you that before using the metal detector, you need to adjust the length of the detection rod. Just unscrew the black rubber through, push and pull the rubber through metal sleeve to a suitable length, and then rotate the rubber inner through tube to make the cable tightly wound , and make the tip of the handle point upwards, and finally screw the black rubber tube tightly to lock the rubber tube sleeve. In this way, when holding the handle of the detector, the thumb is just close to the sensitivity adjustment potentiometer.
The walk through metal detector manufacturer tells you that when adjusting the sensitivity of the metal detector, the detection dish (oscillating coil) should be kept away from the metal, including the paper with aluminum foil, then turn the sensitivity fine-tuning potentiometer knob to turn on the power switch, and turn it to the half position, then Adjust the knob of the coarse potentiometer to stop the audio sound of the speaker, and finally fine-tune the fine potentiometer to make the sound of the speaker just stop. At this time, the sensitivity of the metal detector is the highest. When using a metal detector to detect metal, as long as the detection disc is close to any metal, the speaker will make a sound, and the sound will stop automatically when it is far away from a certain position.