Two-tone solar buzzer (CB20493E)

This circuit was found in a 1991 publication. The transistor can be a general-purpose type.

Debounced Switch 7404 (CB3861E)
This traditional TTL anti-clock setting was found in a 1993 American documentation. The circuit...
Latest Single-Wire Serial EEPROM from Microchip Enables Remote Identification
The AT21CS11 memory device offers an extended voltage range to accommodate lithium-ion battery...
Dual trace for oscilloscope (CB5438E)
This circuit shows on the screen of an oscilloscope two signals alternately at a frequency that depends...