Superscan PI

[GeoMax]

Hi Hassanp,
I don't have a working circuit board. But I've looked at the various schematics here in these posts and they look good at first glance. I couldn't see any obvious errors like you see in other circuit diagrams on the internet. I have not checked every IC pinouts. Many times people write wrong pin numbers at the ICs in the drawing. Have you checked them aginst the manufacturers datasheet?

[profesor]

I am asking friends who have succeeded in building this circuit to help my circuit work and I will give a great project for free to a friend who helps.

I assume you have the necessary measuring instruments to operate this circuit.
oscilloscope .multimeter etc.
1-Before connecting the coil, check the +5v,-5v,-12v,-24v lines. Are there the required voltages?
Check the 3rd leg of the 2-pulse generator 555. See the approximately 90hz pulse signal on the oscilloscope.
3-Make a test coil of approximately 380uh 2R 20cm in diameter and connect it to the circuit with an RG58 cable.
If you have assembled the 4-circuit correctly, connect the TX end and RX end with the coaxial cable.
5-Connect the first channel of the oscilloscope to the output of LM 709.
6-If everything is OK, you will see the signal. Adjust the signal so that GND is in the middle with a 100k trimpot.
Connect the second channel of the oscilloscope to the output terminals of the 6-4538s and see the sampling signals.
7-If everything is correct so far, you should see the metal detection signal on pin 7 of the TL072 opamp on the second channel of the oscilloscope.

[Hassanp]

Hello, my dear friends, thank you for your reply. I have the frequency of 90 Hz on the base 3 oscillator and the base voltages are 5 volts positive and 5 volts negative, 24 volts positive and 12 volts negative on the board and there is no problem. I will inform