Hello...

How to calculate the gain for this circuit because the original output from the bridge is so small and cannot be measured. Thank you

 

There appears to be an error. R7 should go to ground.

hgmjr

 

hello...

i have change it to ground but i forgot to change on the diagram. I need your help on how to calculate the gain for the op amp because the original output from the bridge is too small and cannot be measured. Is there any way how to calculate the gain by calculating the gain based on the resistor attached to the amplifier. Thank you

 

There is - we have it in our Ebook -- http://www.allaboutcircuits.com/vol_3/chpt_8/5.html.

 

If Vin is taken at the input to R4 the gain of the amp is -R6/R4 where the negative sign simply means 180 degree phase inversion. Your amp has a gain of 2200 volts per volt.

 

Hello.

Thank you very much that help me a lot.