Debugging and operation of food metal detector
In addition to the sensitivity regulating potentiometer, the testing and operation of the metal detector for food metal detector does not adjust the part. As long as the welding is not mistaken, the circuit can work properly. The whole machine is static, that is, when loudspeaker doesn't make sound, the total current is about 10mA. When the metal loudspeaker makes a sound, the whole machine current rises to 20mA. A new stacked battery can work for 20~30 hours. If the new welding metal detector can not work properly, it is necessary to check whether the components and wiring of the circuit board are mistaken, the voltage of the battery and the power supply loop are normal, the stable voltage of the VD1 diode is between 5.5 and 6.5V, and the VD2 polarity is not welded. Do not detect the first and the last ends of the oscillating coil inside the disc. Before the metal detector is used, the length of the probe needs to be adjusted. As long as the black glue is loosened, the glue is pushed through the sleeve to the appropriate length, and then the pipe is rotated to tighten the cable, and the tip of the handle is upwards. Finally the black glue is tightened and the rubber sleeve is locked. In this way, when holding the detector handle, the thumb is close to the sensitivity adjusting potentiometer. When adjusting the sensitivity of the metal detector, the probe disk (oscillating coil) should be far away from the metal, including the paper with aluminum foil, and then turn the sensitivity fine-tuning potentiometer knob (FINE TUNING) to open the power switch, rotate to half of the position, and then adjust the roughing potentiometer knob (TUNING) to stop the loudspeaker audio calls, most of which stop the loudspeaker. After fine-tuning fine-tuning potentiometer, the loudspeaker sounds just stop, when the highest sensitivity of metal detectors. When a metal detector detects metal, the loudspeaker will make a sound as long as the detection disc is near any metal, and it will stop automatically when it is away from the location.