The circuit is low impedance, so any rail-to-rail op amp specified for 3V (or less) single ended operation should work.The OP177G does not even come close, but the AD623 might work.
No. pH probes are completely different. I suggest to buy the kit. It is clear that you have no idea what you are doing.
i am mechanical engineering student also i must make mu own circuit board of dissolved oxygen sensor.question 1- why circuit board of pH probes are completely different compared with dissolved oxygen sensors? both of them send millivot and the circuit board must detect voltage. what are differents ?
what are differents ?
i am mechanical engineering student also i must make mu own circuit board of dissolved oxygen sensor.