Reducing from 3.7VDC to 3.0VDC

I am trying to get my guitar hero guitar to run on an old cell phone battery and save myself from buying lots of AA batteries. The problem is I need to change the 3.7 volts from the cell phone into 3.0v for the guitar. I calculated that to get 3.0 volts from the cell battery I had add an 89Ω resistance to the battery. I guess I just want to Know if this is at all possible? It would be nice to use some of my junk parts that are laying around.

use a diode in series that will give you 0.7 V drop across, regardless of the current you will draw.

there is All DC voltages to 3VDC reducer chips. there are 4 pins or three pin modes.

A resistor will not work. As the current varies, so will the voltage drop. Bad idea.

A diode is a bad solution. It means that as the battery voltage falls, so will the supply to the guitar. That means short battery life.

A regulator (LDO) (Low Drop Out) is the ideal answer. That means that 3.0v will be given out while the lithium battery is between 3.8v (fully charged) and 3.2v (probably about the overhead).

Andrew

a diode is the simplest solution.

Depending on the design of the amplifier circuit, it could be that you dont need to do anything at all.

The amplifier may well tolerate 3.7v without any problems, but not knowung the details of the circuit, it is difficult to say.

JimB