The two integrated circuits used in this configuration can still be found. The frequencies of the effects are determined by the capacitors, which may have their values changed.
With 3 transistors, we found this receiver in a documentation from 1966. The circuit has an output...
This sonic relay or vox was found in a Popular Electronics from the 90's. The power MOSFET can be of...
This tri-state comparator was found in a circuit manual from the 1980s, but it can be easily...