Successful HH project

[habitbraker]

Hello everybody! I will make my first post in this forum by showing my HH which I finished today.


You can see that I used IC sockets an socketed many resistors an made many jumpers so that when I will get scope I could experiment alot.



This funny coil (6cm ) Is just for testing. This even isnt made for HH. I made it for simple BFO probe an it is center tapped. But its works ! I dont have adjusted pulse lenght, delay an dont have calculated damping but I can detect 15mm coin about 10cm far.

So everything is just started an lot of experimenting and learning will be done

Thanks Carl for this great design!!

[GoldenKiwi]

Hi habitbraker, congratulations, well done!

[habitbraker]

thanks!! Saw yours too - great work!

So I had time and I put everything on handle. I got question about coil shielding. Why it is needed and what are the indicators that I need it? (Acctually a got a hunch) Doesnt it affect sensivity?

[habitbraker]

How much voltage should be at TP5 with coila connected and no target?

I got 3,5V with coil and no target indoors.
Without coil its around 0V

Doesnt it mean that amp is pretty overloaded so its affect sensivity?