This circuit is from a Radio Electronics from March 1960. The generator works with a 22.5 V battery, generating good intensity signals determined by the LC circuit.
This circuit was found in a 1969 Mullard publication. The transistor may be the modern equivalent...
This circuit uses an operational like to the 741 having been found in a 2001 documentation. The...
Found in English documentation, this timer produces an audio signal at the end of the timing. The...