Explaining the Clone PI detector schematic

[Hesamavr]

hello,

is there anybody to explain the duty of the 4 opamps (TL074) in the below schematic of the Clone PI detector?

[waltr]

U1a- Pre-amp, Gain =10
U1b- second amp, Gain = 56 with Switch U2C is open, G = 1 with U2C closed
U1c- Integrator, Adds signal when switch U2a is closed (Sampling switch). Switch U2D 'resets' integrator.
U1d- Active pre-amp clamp, helps prevent U1a from saturating and improves recovery to allow earlier sampling

[rickb]

Hesamavr:

Your post has nothing to do with the book "Inside the Metal Detector". Please restart your thread in the the Tech forum.

[Hesamavr]

Hesamavr:

Your post has nothing to do with the book "Inside the Metal Detector". Please restart your thread in the the Tech forum.

I did