An LED that flashes is more economical than a constant LED that is at the same brightness, but it also attracts more attention. For this reason, this mode of operation of LEDs is quite often used in advertising installations of any kind.
Instructions
Step 1
If you are not versed in electronics, get a dedicated flashing LED. Connect it to a voltage source in the correct polarity and across a resistor. Use the same method for selecting this resistor as for conventional LEDs.
Step 2
In order to make several LEDs blink at the same time, and not in a confusion, calculate in the usual way a chain of a resistor and several non-blinking LEDs connected in series. Replace one LED in this string with a blinking one.
Step 3
In order to make LEDs not equipped with a built-in control circuit blink, assemble such a circuit yourself. To do this, take any two low-power low-frequency transistors (one p-n-p structure and one n-p-n structure), two resistors - one for 200 ohms and the other for 100 kΩ, as well as an electrolytic capacitor with a capacity of 10 picofarads, designed for a voltage of at least 16 V.
Step 4
Connect the collector of the n-p-n transistor to the base of the p-n-p transistor directly.
Step 5
Connect the collector of the p-n-p transistor to the base of the n-p-n transistor through a capacitor, with its positive plate facing toward the collector of the p-n-p transistor.
Step 6
Connect the emitter of the PNP transistor to the base of the NPN transistor with a 100K resistor.
Step 7
Connect the emitter of the n-p-n transistor to the common wire.
Step 8
Connect the anode of the LED to the collector of the pnp structure transistor directly.
Step 9
Connect the LED cathode to common with a 200 ohm resistor.
Step 10
Apply a voltage of about 5 V with the positive pole to the emitter of the p-n-p transistor, and negative to the common wire. The LED should blink. If this does not happen, turn off the power and select other transistors (of the same structure), then check the operation of the device again.
