How does groundbalance exactly work on a VLf

[Prospekteur]

Hi, eventually a dumb question

.....but what does exactly happen when we use the groundbalance potentiometer? I know how to use and know a bit about the electronics also I build several units. But would be nice if some of the professionals here can explain me exactly what happens exactly in the elecronic parts. I will also check my books now.....I think Ive read something about it in the past;-)

[Prospekteur]

Ok I found it. "Inside the metal detector", site 87-91. A very good explanation;-)