My first pulse induction metal detector works and i am casing up and just working out the coil housing , my thoughts are going to mark 2 .
I am making more as i have a few kids and daddy wants hes own !
What i want on the second one is a more simple power supply for a start !
Looking at a few versions of a Pulse induction type of detector again most were modified versions of the hammer head Pi so all have dual power supplies at best .
I came across this site
http://oldradiobuilder.com/mdetsp.html
and had the main schematic below which i liked but the ic's are hard to get .
I came across a forum some one had the idea to change the parts of that design and see if they could make a simple as possible pulse induction type .
Why i am posting the schematics up is i want to use a 4528 monostable instead of the 4538 as far as i can see they are pin for pin the same ?
i have a TL072 as a replacement for the 71 just i have one handy the 72 is a dual opamp i think the 71 is a single of the same family.
Also i am not sure about the last version in that the circuit for the TL071 is simplified .
Just running it past any one that wants to have a look and may pick up any problems on any of those circuits .
As far as i can see most of it makes sense .