Converting the radio into a 30 cm depth metal detector

 

The metal detector in our explanation today on this topic consists of the transmitter, which consists of the transmitter, where the first transistor with the first file sends an electromagnetic signal with the same value as the signal sent by the second transistor in the second file, and here we control the signal coming out of the circuit through a variable capacitor or two capacitors two variables on the device files. This method consists of transistor No. (2), capacitor 104 (8), capacitor 220 micron, and a resistance of 10 kOhm (4). Here, a radio is connected to both ends of a coil to get the total frequency. For the other coil they are connected to a variable capacitor to adjust the signal. The third transistor is a frequency mixer and amplifier transistor.

After the mixer stage, the device goes through the first amplification stage, which is the stage of mixing the two frequencies together and showing the difference with the amplification, and as we said earlier, the sound appears clearly on the radio.

 The most important thing about this method is that we can use a large file of 30 * 60 size and get a depth of at least a meter and a quarter of a large metal, and connect the output of the third transistor in the mixer to the terminal of the radio antenna and the negative of the circuit to the negative of the radio wave.

What distinguishes this device and this topic is that we connected the large file 30 * 60 to this circle and we got a depth of about a meter, which is an excellent depth for these devices

This metal detector can work on all radio waves, long and short

Here is the video, a beautiful video to show the excellent depth in converting the radio into a metal detector. For any inquiries, please write it in the comment

This picture is illustrative of the circuit with the radio, paying attention to the transistor legs, depending on the transistor being used:

Transistors that have been tested and work efficiently, and you can choose one or more of them in the same circuit, as follows:

 2n5551..... 2n5550 ..... 2n3904 ..... bc550 .... 

.....c1815... bc549 .... bc548 ..... bc547 .... bc546