We found this circuit with the LM3914 IC in a Radio Electronics magazine from June 1985. The circuit is intended for monitoring the battery voltage through an LED bar.
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...