In the past days with the valuable help of Matteo L. we realised 4 NIM-modules able to filter an input signal with a lowpass filter of 2 order (cut frequency at 100 Hz) and to amplify it of a factor 100.
The scheme of the circuit, using a multiple feedback (MFB) filter, drawn with the software LTSpace is shown picture 1 and its transfer function in picture 2.
Each module can process two channels, so in total we have 8 available filters+amplifiers.
A picture of the circuits and the module are shown in attached files 3 and 4.
They will be used to filter and amplify the output signal of the PSD used for the filter cavity optical levers, replacing the stanfords that have been doing this job up to now.