# Cutting Down Power Sources

#### aroumanidakis

Joined Mar 25, 2009
3
Hello, I'm working on a project, and I need to run a device running on three 9v batteries on one power source. I can't exactly figure out how to pull this off however, because one lead has power from one source, and ground from another source hooked together at the same spot. So the layout looks similar to this

P=Power #
G=Ground#

L1----P1

L2----P2
L2----G1

L3----G2

L4----P3

L5----G3

I've included pictures of the circuit

#### Attachments

• 128.4 KB Views: 17
• 147.3 KB Views: 16
• 23.5 KB Views: 11

#### thatoneguy

Joined Feb 19, 2009
6,349
It appears to use a "Virtual Ground" between two of the three batteries, so that +9V and -9V are available, 18V total. Usually in op-amp related circuits. The 3rd 9V appears to run another section of the circuit, with the + of one 9V and the - of the other two 9V as a common ground.

There isn't a simple way to change the existing to one 9V.

What is the function of the device? Is there a way to get clearer pictures?

#### aroumanidakis

Joined Mar 25, 2009
3
It appears to use a "Virtual Ground" between two of the three batteries, so that +9V and -9V are available, 18V total. Usually in op-amp related circuits. The 3rd 9V appears to run another section of the circuit, with the + of one 9V and the - of the other two 9V as a common ground.

There isn't a simple way to change the existing to one 9V.

What is the function of the device? Is there a way to get clearer pictures?
Well, we just need to run it off of one source, the voltage doesn't matter right now. If it needs 18v it can be done. The device is a metal detector, and I can see about using a better camera today.

#### thatoneguy

Joined Feb 19, 2009
6,349
Need better pictures, might be able to use two batteries, unsure what all is in the circuit.

Somebody else may have better ideas as well once details are visible.