Robin2:
If your amplifier is giving output voltages between 0 and 1 volt its hard to understand how the Arduino ADC is not reading them. I am really thinking of something in the region of 0.5 volts for testing. What is the output impedance of the amplifier? The Arduino ADC likes it to be 10k or less.Have you tried making a simple voltage divider with a potentiometer that gives similar votages and testing whether the Arduino ADC can read those voltages correctly?
I think you need to show us a diagram of how you have everything wired up. A photo of a clear pencil sketch will be fine.
...R
That is a really good idea, I will try out the divider and see how arduino behaves. Sure, I will see if I can make a little sketch later today.
Thank you.
EDIT: Voltage divider method also works fine and the arduino can read pretty low values.