- #1
nadersb
- 28
- 0
hello,
I have a strange problem!
I wanted to amplify my signal and i used 2op amps, each of them has a feedback resistor between (-) pin and output( pin 2 and 6 in 741) the ratio of resistors(r2/r1) is 150, but my signal only amplify 5times! I change the R2 resistor but nothing changed! i put different resistors but all of them had the same results! I changed my op amp but still the same results! the second op amp worked perfectly but the first stage has this problem!
does anybody have an idea what's wrong with the op amp?! you can see the circuit in the link below:( the value of capacitors are 0.47uf and the first feedback resistor is not 1M it is 1.5M)
http://www.2shared.com/photo/a_JmZITS/Untitled.html
I have a strange problem!
I wanted to amplify my signal and i used 2op amps, each of them has a feedback resistor between (-) pin and output( pin 2 and 6 in 741) the ratio of resistors(r2/r1) is 150, but my signal only amplify 5times! I change the R2 resistor but nothing changed! i put different resistors but all of them had the same results! I changed my op amp but still the same results! the second op amp worked perfectly but the first stage has this problem!
does anybody have an idea what's wrong with the op amp?! you can see the circuit in the link below:( the value of capacitors are 0.47uf and the first feedback resistor is not 1M it is 1.5M)
http://www.2shared.com/photo/a_JmZITS/Untitled.html