increase gain surfmaster

[giuseppem94]

I would like to change the gain of my homebuilt Surfmaster (first version, not pro), formulated on I saw that you can do by changing the values of some resistors and capacitors, but I have not found the exact values, could someone tell me the new values to increase gain?
What will change if I increase the gain? improves the detection of gold, the stability?

[Silver Dollar]

You already have lots of gain.
Some people break the gain into 2 stages to allow for sampling closer to the turn off.
You could get the Pro schematic off here and make those changes to upgrade yours.
Other changes are strictly experimental and should be done with a bit of knowledge
and a good scope.

I don't have both schematics handy but if you post them here I could help identify the
differences so you can do the upgrade.