DIY Surf Pi

Hello this is DIY Surf Pi Pro Pulsinduction Metal Detctor please put volume up the sound noise nearby video capture was too high sorry it was a plane your can hear first light signal at around 35 cm for a 2€ coin by pumping up and down at swinging good signal around 30-32cm not fine tuned already has to find out the best coil and then i will set while measuring output of ic´s thanks for looking regards