explain me hw it wrks

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reshmikc

New Member

• Sep 14, 2011

• #1

i am attaching a circuit diagram along this. can anyone help me by explaning how it works

 

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B

BrownOut

Banned

• Sep 14, 2011

• #2

The opamp is a simple multivibrator, that produces a square wave at it's output. Not sure what the "test points" are for, but if you conect a resistor across the two points, the LED's should flash alternately.

 

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reshmikc

New Member

• Sep 14, 2011

• #3

that circuit is actually a diode tester circuit.test points are for fixing that diode.so sir as u said instead of keepig that resistor by placing a diode if it is working led glows rgt?

 

audioguru

Well-Known Member

Most Helpful Member

• Sep 14, 2011

• #4

If you do not have a resistor in series with a diode being tested then the diode plus LEDs short the output of the opamp then it doesn't work.

 

audioguru

Well-Known Member

Most Helpful Member

• Sep 14, 2011

• #5

Why do you have two threads exactly the same??
The moderator should delete the other one.

 

AnalogKid

Well-Known Member

Most Helpful Member

• Sep 23, 2011

• #6

They're probably counting on the 741's internal current limiting to protect both its own output stage and limit the current through the diodes.