How to assemble a simple flashing light of the available radio components

Any radio amateur wishes to collect any grandiose setting, but most always starts out small, and if you just at the beginning, it is better to gain experience when assembling simple circuits that you will be able to collect even with his child. In this article, we are together with you collect a simple blinker of the components that you can find and vypayat from an old radio. She must be found in the garage or in the attic.

Driving flashers

So, let us carefully examine the concept of our future with you flashers.

The basis of the above protocol is symmetrical multivibrator. A principle of operation of the scheme lies in the following:

Transistors, indicated in the diagram VT1 and VT2, alternately opened. In the open position through a chain of emitter - collector current flows, which causes the light from the LED HL1 and HL2.

In this open-close frequency transition, and hence the frequency of flashing the LEDs included in the circuit can be approximately calculated from the following formula:

As seen from the above formula, in order to change the flashing frequency, it is sufficient to change the denomination or the resistor R2 (the resistance is equal to R3), either of the capacitor C1 (capacitance C2 is identical).

At the same time, in order to properly calculate the frequency of resistance in kiloomah record, and the capacity in microfarads. The frequency is measured in hertz (Hz).

For example, if we take 47 uF capacitors, and the resistors 27 ohm, the flashing frequency will be approximately equal to 0.5 Hz, i.e. the LEDs will flash with a frequency of approximately one per two blinking seconds.

If you take the capacitors of different capacities, our multivibrator turns from synchronous to asynchronous, that is, the LEDs will light up one another longer.

For modulating the flashing frequency sufficient to make an additional circuit element in the form of the variable resistor circuit and acquires the following form:

So now let's implement theoretical knowledge to practical experience.

We prepare the necessary details

So, we are with you the successful assembly of need:

1. A pair of transistors. It really does not matter what brand they are. Most importantly, they were N-P-N type.

2. A pair of electrolytic capacitors. Capacity can be selected in the range from 10 to 100 microfarads, and the voltage must be higher than 6.3 volts.

3. Resistors. Wherein R1 and R4 330 ohms nominal value of 0.125 W power dissipation, and R2 and R3 can be selected in the range of from 22 ohms to 27 ohms. I chose the resistors of 1 ohm power dissipation as 0,125 watts.

4. A pair of LEDs.

5. Power Supply. To our collected scheme to work, you need just regulated power supply connected in parallel or three penlight batteries. I'll use a regulated power supply

KPS-3010DF, reviewed here.

The assembly process and testing of circuit

In fact, the scheme is very simple and should not cause any difficulties in implementation. At the end of the build you should get the following construction:

Demonstration of the operation of the circuit with continuously variable blinking frequency is represented as follows.

conclusion

The scheme is simple and it can even you collect with your child and it may thus encourage him to study physics and electronics. Like this, then vote it Like. This will allow to show it to as many people. Thanks for attention!