LED FLASHER

  
The circuit uses a flashing   
LED to flash a super-bright
  20,000mcd white LED

LED FLASHER WITH ONE TRANSISTOR!

This is a novel flasher circuit using a single driver transistor that takes its flashrate from a flashing LED. The
flasher in the photo is 3mm. An ordinary LED will not work. The flash rate cannot be altered by the brightness of the high-bright white LED can be adjusted by altering the 1 resistor across the 100u electrolytic to 4k7 or 10k. The 1k resistor discharges the 100u so that when the transistor turns on, the charging current into the 100u illuminates the white LED. If a 10k discharge resistor is used, the 100u is not fully discharged and the LED does not flash as bright. All the parts in the photo are in the same places as in the circuit diagram to
make it easy to see how the parts are connected.

LED FLASHER

These two circuits will flash a LED very bright and consume less than 2mA average current. The second circuit allows you to use a high power NPN transistor as the driver if a number of LEDs need to bee driven. The second circuit is the basis for a simple motor speed control. See note on 330k in Flashing Two LEDs below.