Using only an ultra-bright white LED, red blinking LED, PNP transistor, and a diode, the circuit gives a strong visual indication of current consumption by blinking brighter and more frequently as ...

The test circuit used 17 "slave" LEDs plus the flashing LED. Peak collector current measured 155 mA using the 3-V rail. A final version of the circuit incorporated a surface-mount transistor and ...

Of course, blinking LEDs isn’t the sole purpose of a multivibrator. ... Using a darlington transistor (such as MPSA14) in place of 2N3904 can improve it. Report comment. Reply.