Despite being from a 1969 publication, the transistors used have current equivalents such as BC548 and BC558. The circuit generates signals from 1 500 to 20 000 Hz and 4 scales.
This circuit generates frequencies determined by R3 and C1. We found it in the Radio Electronics magazine...
Found in a 90s Elektor, this circuit makes use of general-purpose transistors, except T4 that can...
This circuit is based on a component from the time, the MSM0322 integrated circuit. It modifies the...