i was be told by using the LM741Cn the circuit will not working its tru or not.. i have made a emg circuit by using lm741cn, until now the circuit not working,... i really frustrated by troubleshoot for many time.. need help

 

here i has attached the circuit i made
View attachment 12.bmp

 

Correct. LM741 opamp is a poor choice. It is 40 years old and past its best due date.
Select a modern instrumentation amplifier that provides high CMRR.

 

thank you for read my thread..
can give some example..

 

thank you for read my thread..
Can give some example..

op37, opa365, ca3240, tlc272, lm358 are just a few.....

 

Making R1 and R2 not match seems the wrong thing to do. U2 and U3 seem to be drawn wrong because they are just square wave generators the way they are drawn now. The labels on the capacitors are difficult to read. One of the worst difficulties with the LM741 is the dead zones near the power supply voltages, but no power supply voltages have been listed.

Fixing these things will make this easier for the rest of us.

 

Check out this video and this video. The guy mentions specific ICs to use. I have no idea how good his advice is, as I haven't tried out his circuit yet. I am also interested in EMG signal processing. I have just ordered EMG sensors that should arrive tomorrow. Maybe in the near future I will have more practical advice for you.

 

http://www.youtube.com/watch?v=H-WiHlVN_uw

i follow the circuit on this youtube.. on the end of video, he made it to working.. but on my case it not working.. why.. any problem with the circuit

 

View attachment 122.bmp

my new design.. i follow instruction from #12.. please help me..

 

value capaciot is 100nano and 50 nano

 

The input labels on U2 and U3 are backwards.
You fixed the resistor network properly then labeled the amplifiers backwards.

 

can you tell me, how voltage input and frequencies that electrodes detect

 

i already take your advice but it still same.. i also change the op amp to lm 358p.. still not working.. please help any circuit that suitable so that i can continue my final project.. the due date are near..

 

I see about 8 Hz to 700 Hz.

 

can i make ina118 concept by using lm358N.. on my electronics market.. i do not found any ina118 or ina128