I, Made it work , so it's working just like Gary shows in the pictures.You have to be aware of some things like the coil lets say if you look at the shematics legend you will see that the polaraties in the coil is oposite, and you have to remove 2k2 resistor witch is just before the potenciometter /if you use bigger coil it wont oscilate if you dont.The first transistor 3904 is all the time open and work as an aplifire and by turning the pot you are adjusting the curent that goes to the 5088 witch is a switch that grounds the 555 timer and make it stop beeping. It took me a while to find out hou its working so I can make it work if you play with it for a while it will do.You can use a diode with 100 k resistor to see if you have make a good cirquit 3904 it have to be open all the time and if you disconect its colector leg /with a coil wired/ the beeper have to stop wich means that 5088 is wired correctly. At first I tried to make it with the pcb but after I have use the shematic and I think is better if you try to understand how it works.I m an absolute beginer in electronics it's actualy my first try and I'm so happy that I made it wirk. Sorry for my bad english by the way. If someone have the shematics for Garys Pulse metal detector 1 or 2 I will be happy to try to make it as my second project.
Ok I see! The page is down so it looks like I'm the last one to do pin pointer 3. I'm starting to make updates If I make it work bether..Now I'm trying to make it set automaticly the best setting I will keep you in touch.