Two-transistor astable / flashing LEDs
This is a classic circuit using capacitors, resistors and transistors to alternately flash two LEDs. Could be used to make a warning sign or as the basis of other oscillator-based projects (such as a miniature electronics organ). Supplied with a PP3 clip so that it can be powered from a standard 9v battery.
This kit is available in packs of 8 or more – see the Prices and Ordering page for details.