We found this configuration in a 1974 publication. Transistors can be replaced with equivalents such as 2N2222. The circuit has a dynamic range of 60 dB.
This crystal configuration can be made with triggers of any logic. The frequency is given by the...
Only two transistors are used in this preamp for low-sensitive transducers, such as guitar and...
This project from a 1983 publication can be assembled using more modern transistors. We can use...