No standard problem there is no standard answer, just only guessing answer and guessing problem.

1. What kind of the power supply? (liner power, battery, switching power.)
2. How is the input frequency?
3. What are the waveforms of +15V, -15V, ground, outpout?
4. Which op amp were you really used in breadboard or PCB?

 

There's too many "maybe's" in this problem.

Hi,

So it's just like real life then
From the first post and post #6 it appears that he has common mode noise and wants to get rid of it.

He has to come back to clarify some things of course, unless maybe he found the answer already. I have a feeling that happens sometimes, where people ask the question but then get the answer from some other source either online or offline and then dont get back to proclaim any success because they are busy implementing that solution.

 

Hi,

So it's just like real life then
From the first post and post #6 it appears that he has common mode noise and wants to get rid of it.

He has to come back to clarify some things of course, unless maybe he found the answer already. I have a feeling that happens sometimes, where people ask the question but then get the answer from some other source either online or offline and then dont get back to proclaim any success because they are busy implementing that solution.

What you said that it also happened in Taiwan, the TS will spread out their questions in some forums, when they got the answer then never come back again.

 

What you said that it also happened in Taiwan, the TS will spread out their questions in some forums, when they got the answer then never come back again.

Another factor is the due date. If they don't get someone to work their problem for them by the time it's due, then they figure there's no point going any further since they only wanted an answer in order to get some points and don't have any interest in actually learning anything.

 

Another factor is the due date. If they don't get someone to work their problem for them by the time it's due, then they figure there's no point going any further since they only wanted an answer in order to get some points and don't have any interest in actually learning anything.

Yes, and the TS only 2 posts in this thread .

I found a sadly true, the helper on the internet are more enthusiastic to offering the solutions, but many posters that they seem treated it as a free lunch.

I met some internet user in the DIYer forums to asked for help and not just to get a works circuit that they even asked someone to do the layout for him, or soldering for him, sometimes that I really like to ask this in my mind : Could you sharing your money to me? ...

 

hey!
please,can anyone tell me the difference between TL084, LM318 and LM741?!
I wanna know which one is better for the circuit shown in the figure if the input signal is noisy and the same amount of noise exists on the ground signal also wanna know why .
thanks in advance..

Unwanted ground loop established in a circut can be major cause of noise or hum...check any ground loop in your circut.....A a ground loop develops because each ground is usually tied to a different earth potential(real life conditions) This condition allows current to flow between the grounds by way of the process loop,which can be a cause of noise in your circuit...

 

I can tell you I haven't seen this question from any posters in the same time frame at ETO. Here and ETO are the two forums I visit.

The forums I know that have a homework help section are: AAC, ETO, EDA, and EP

http://www.electro-tech-online.com/
http://www.edaboard.com/forum.php (forum is called "Electronic Elementary Questions") which is close enough to "homework help"
http://www.electronicspoint.com/