This tone recognizer circuit that relies on R5 and C1 was found in the December 1994 issue of Electronics Now. The circuit operates on voltages from 6 to 12 V typically.
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...