Privacy Policy
Multivibrator » Electronics » Basic Circuits » Multivibrator » Let's go... » Experiment 9 -astable MV II

Experiment 9 - The astable Multivibrator II

Take the shown circuit into consideration. You have replaced the capacitor C1 by a capacitor with a capacity of 100 μF.

Circuit of an astable multivibrator. (Enlarge)

Circuit diagram of a astable multivibrator.

The multivibrator remains significantly longer in one of the two states.

In fact you can calculate the switching times T1 and T2 by using the formula...

T1 = R2C1 × 0.693

T2 = R3C2 × 0.693

(Want to know where this formula comes from? See Experiment 25.)

Put the values into the formula to get...

T1 = 47,000 Ω × 0.0001 F × 0.693 = ca. 3.3 sec.

T2 = 47,000 Ω × 0.00001 F × 0.693 = ca. 0.3 sec.

From the formula you can see that the resistors R2 and R3 influence the switching time. However, you are not free to choose any resistance value. This you investigate in Experiment 26.

In the next experiment, you change the astable multivibrator a little bit...