Opamp setup doubt

Using Arduino Audio
93

Marciokoko:
Right, but at this moment I still have the 2 batteries making up a split supply +9V and -9V. Thats what I mean by "I have connected to GND and some connected to Vcc-).

Im thinking I should move the:

GND opamp
100uF (Vo) thru 10k R
2n3906 collector

to real GND from the supply, 0V.

The two 9V batteries will be connected like this...

  • -******+ -

The starred symbols represent the connecting wire between the - terminal of battery #1 and the + terminal of battery #2.

The wire will become the '0V' side of things (itself).

  • -*******+ -

*0V

The + terminal battery #1 will be +9V.
The - terminal of battery #2 will be -9V.

The connecting wire itself will be 0V.

And, if we're working with arduino...... we also usually connect that wire (0V) to the GND pin of the arduino as well.