The problem of simulation of sine wave generator

[hfc1993911hfc]

the following is the circuit of a bubba oscillator sketched by multisim , but I can/t get the expected output. The oscillator only shows a 6V DC .It seems that it cannot oscillate by itself, who can help me ?

 

[FvM]

You need to cause a deviation from equilibrium to make the circuit oscillate in simulation. A simple method is to skip the initial transient solution. Otherwise inject a small "kick-start" pulse. If the pulse shows an oscillation of decreasing amplitude, increase the loop gain.

 

[hfc1993911hfc]

You need to cause a deviation from equilibrium to make the circuit oscillate in simulation. A simple method is to skip the initial transient solution. Otherwise inject a small "kick-start" pulse. If the pulse shows an oscillation of decreasing amplitude, increase the loop gain.

yeah, I am not sure how to introduce a 'kick--start' pulse ,can you explain it in detail or draw it for me ? thx very much.

 

[FvM]

This is a two part suggestion. Did you try the first part. (See Multisim manual: Setting Transient Analysis Parameters, Initial conditions: Set to Zero).

 

[zorro]

There is something wrong: The left terminal of R4 should be connected to the noninverting input of U2A.

Z

 

[hfc1993911hfc]

no , R4 should be connect to the inverting terminal of U2A

 

[zorro]

Oh, sorry, I intended to say that but confused the name