Simple 2 led flasher circuit

Hi guys I am new here so please have patience wit me. I need a simple 2 led flasher with transistors but not with a 555 ic. The ones I found on the internet doesn't perform as they claim. Thus I don't post any circuit diagrams. Must work from 3v to 4.5v.

by Daniedp76
September 04, 2021
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1 Answer

Answer by vanderghast

Multivibrator circuit

This multivibrator has two major problems.

First, in a material realization, the flashing can be too fast to be registered by the human eyes, so you may feel that it is not working, while it does. Use an oscilloscope.

Second, the simulators have numerical problem if R1=R4 and R2=R3, and would NOT show any oscillation if the circuit is too symmetrical. You have to add some difference in the values to exhibit the oscillation. Here, if you run the time domain simulation, you should see the oscillation, with the non-symetrical values.

+1 vote
by vanderghast
September 06, 2021
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