I have been working on replacing a test setup at my company that utilizes a Lock In Amplifier, and I am running into some issues due to a lack of understanding on my part.
To preface this, I will say that the test equipment is most likely from the 1970's (8-CFA by Vibro-Meter) and unfortunately after it was acquired by us, it no longer functions. The application is measuring a bridge voltage that has been excited by an AC signal. I gather that the system I am trying to replicate is working on a wheatstone bridge that has been excited by an 8 KHz signal. I am assuming that the bridge voltage is being used as the input for the lock in amplifier. The output was then read on an oscilloscope. The bridge voltage that I am trying to detect will most likely be on the level of 1 µV.
I am hoping to use the board as a replacement for the broken equipment. If I am understanding this correctly, if I ensure that my bridge supply voltage is a 6.25 KHz signal, that is in sync, I should get a DC voltage at the output of the board that could then be measured using a DMM or an oscilloscope?
Is there anything that I am missing?
Thanks in advance for the help.