One-second timer (CB22059E)

Obviously longer intervals can be obtained with this timer found in old documentation. The indicator is an LED, and the time is set in VR1.

Voltage Comparator (CB6549E)
This circuit uses amplifiers from the 60's American company Microlin. The circuit can be designed...
SCR 600 W Control (CB13900E)
This power control from Motorola's 1971 SCR Power Control Fudamentals can control full wave loads...
Audio signal generator (CB8044E)
Despite being from a 1969 publication, the transistors used have current equivalents such as BC548 and...