This conventional filter circuit is from American documentation from the 1990s. The operational amplifier admits an equivalent and the power supply must be symmetrical.
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...