Mt8870 Proteus Lib 35 -

If the component doesn't show up despite copying the files:

In the context of the MT8870 and Proteus, "35" likely refers to: mt8870 proteus lib 35

Since the MT8870 is not native, you must import a third-party library. Here is the safe, functional method to add the DTMF decoder. If the component doesn't show up despite copying