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Is the circuit ok? also please explain "What the circuit is doing"? Answered

The circuit shown is supposed to produce AC where v1 is a 9v battery, c1,c2,c3,c4 are capacitors and t1 is  a transistor (BD140), R1 is a resistance

AC squarewave of 140-150 kHz is required .........sorry for poor image quality please use "magnifier " if needed.....Thanx in advnce!

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user
jatinbatra (author)2013-01-03

I have tried simulating it but output is weird
i'm getting0voltage supply
any changes in circuit ?
http://www.docircuits.com/circuit/display/id/224

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mpilchfamily (author)jatinbatra2013-01-03

Why are you trying to use this design?

The design doesn't work because the +V doesn't have any way of reaching the output. Follow your connections. Each circle is a connection point between multiple lines. Any other lines crossing each other are not connected. So V+ is connect directly to ground through C4 and thats it. Everything else is only connected to the ground side of the circuit. All that circuit is doing is charging C4 to the same voltage as V1. All the other components are only connected to ground so you don't have a completed circuit there.

What you need to do is drop this circuit and start fresh. Unless you know what your doing with designing a frequency generator your not going to be able to sort it out. So find a known working circuit. All you need to do is goolge for a frequency generator schematic and you'll find many workable options.

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user
steveastrouk (author)2013-01-02
user
jatinbatra (author)steveastrouk2013-01-02

can u explain what is circuit doing?

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iceng (author)jatinbatra2013-01-02

R1, C1, C3 and one side of the output are only connected
to ground through C2, T1 and the base emitter junction.

There is no connection to +V1 !!!

Sorry  the  CIRCUIT  DOES  NOTHING as it is drawn.

A

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user
jatinbatra (author)iceng2013-01-03

i didn't get...can u explain further?

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user
steveastrouk (author)jatinbatra2013-01-03

There's no supply of power to the output.

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mpilchfamily (author)2013-01-02

I could be wrong but i don't think that will produce a square wave for you. My knowledge in this area is limited but i think you will need a PWM circuit to generate a good clean square wave. You could use a micro controller that has PWM to generate 150 Hz easily. All you would have to do is program it and your good to go.

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jatinbatra (author)mpilchfamily2013-01-02

if possible please explain in detail...and what is this circuit doing...and please see again i have updated it!

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mpilchfamily (author)jatinbatra2013-01-02

That circuit will likely create a sign wave. Like i said my knowledge is limited here. So i'm unable to explain exactly how it will all work.

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mpilchfamily (author)2013-01-02

Depends... what are you trying to accomplish? What kind of AC output are you looking to get?

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jatinbatra (author)mpilchfamily2013-01-02

i am looking for squarewave of some 150 kHz frequency

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