This sound intensity meter was found in a 90s Elektor. The circuit uses an integrated device from the time that is not common today. The indicator is a milliammeter.
This 1 kHz circuit was found in American documentation from the 90s. The original operational...
January 2017 - Atmel / Microchip's ATA8520 single-chip card for SIGFOX RF transceivers can be...
This oscillator was found in a 1967 General Electric documentation. The UJT is P-channel, an unusual...