Suggested for the control of photographic enlargers, this 1967 General Electric circuit uses still common components. The circuit directly controls a lamp for exposing negatives.
This high-gain circuit uses junction FETs (JFETs) and must be powered by somewhat high voltages. The...
This circuit counts 1 per second, displaying the value in binary. The circuit is TTL and must be...
Critical components of this project are the Geiger tube and the 300V battery. The battery can be...