Thank you :) I want to understand the charging and charge measuring process better. A year ago I tried to just put the piezo nozzle, charge electrode and charge sensor together and tried to measure the charge, but it did not work very well and when I broke one amplifier I also saw that the result was not repeatable with other amplifiers. Now I want to try it step by step, starting with large drops at low frequency and a simple setup. My plan is to build my own amplifier next for measuring these drops and if everything works well I want to increase the drop frequency and reduce the drop diameter until ultimately ending up at 0.1mm drops at 40000 to 60000 drops per second for the CIJ printer. What I learned so far is that shielding seems to be very important to not pick up noise like the mains frequency with your charge sensor on the way to the amplifier.
