Help With 180 Degree Phase Shift

[Schmoopsiepoo]

I want to take an audio signal, and shift the waveform 180 degrees. How would I do this? I have read that if you take a simple class a amplifier, and feed the signal into the base of the NPN transistor, you will get an output that is shifted 180 degress. Example:

Will this work?

 

[Bobbywhy]

Schmoopsiepoo, Welcome to Physics Forums!

The Example you posted has a red "X" inside it and does not work. But you are correct about a class "A" amplifier: its output is 180 degrees out of phase with the input.

 

[dlgoff]

Another way would be to use a Operational Amplifier (op-amp) configured like this:

You can find many other way to use these fairly simple integrated circuits here:

http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/opampvar.html