This is a combined circuit of tone generator and preamplifier. We found it in a 1975 documentation. Operational amplifiers of that time can be replaced by modern equivalents.
This circuit detects traffic problems on a miniature railway by triggering an alarm. The circuit was...
When establishing the voltage at the input of this regulator, the output voltage rises smoothly until...
This circuit was found in a Motorola documentation from 1975. Modern equivalent transistors such...