The transistors of this circuit found in an English 1980s documentation may be the modern BC548 equivalents. The circuit is battery powered and the earphone must be crystal.
This circuit, which uses a planar silicon sensor, is from a 1964 Electronic Design. The component...
We found this circuit in a technical documentation from Texas Instruments. The circuit can be...
This well-known configuration of the guitar effects pedal was obtained in an English magazine from...