This is my replacement of the original Elektor Formant RFM module. It follows closely the original. Because this one is for my Next Generation Formant project i started with the original Elektor Formant RFM schematic and added my changes to the design. All parts are updated to today (2017/10) available parts. The connections are the same as in the original to keep the possibility for internal wiring. If you don’t need those features just leave them out. This PCB provides all functions as in the original Elektor Formant RFM. The only change I have made is adding a wet/dry potentiometer. So you can adjust the balance between the input signal and the filtered signal
The schematic follows closely the original Elektor Formant RFM. For details refer to the original documentation.