Found in a 1990s American documentation, this circuit provides an output voltage approximately 4 times that of the input voltage. Diodes are general-purpose types.
This circuit was found in an old GE manual. It uses a thermocouple as a sensor. The SCR must be in...
This circuit is from a 90s Popular Electronics. It appears elsewhere on this site. Q1 can be any...
This circuit generates sinusoidal signals between 300 and 3000 Hz. We find a 303 Circuits from the 90's....