Eliminating Background Noise using Labview

[Solis]

Hello,

I have built a VI that is used to measure voltage from an amplifier connected to a photomultiplier tube.  The PMT reads a fluorescent light signal and sends it to the amplifier, which converts current to voltage.  I get a pretty decent signal reading, but I want to cut down the background noise that shows up.  For some reason, the background noise starts around 1.5V and randomly oscillates between 1.42 volts and 1.54V.  I am trying to find a way to cut down the noise so my readings are a little more clean.  I have attached my VI and a picture of the resulting graphs I get from a typical data run.  The left graph shows background noise in a 4second interval, and the right graph shows the complete run. 

Any help, suggestions or comments is very much appreciated.  Thank you!

[viScience]

It seems like you have plenty of S/N and can just use a peak detector to get at the essential data.

Otherwise you could try a median filter but it could easily wipe out your peaks if you are not careful.

[billko]

Looks pretty clean to me.  Just curious, why do you need it to look cleaner than that?