I am using Vishay 120 ohm Strain Gauges, (specifically EA-06-062AP-120) to try and generalize certain readings taken from aircraft engines. We have set up a small device to vibrate to simulate an engine on a small scale. The strain gauge is mounted to this device and the leads are then attached from the strain gauge terminals to a low noise signal amplifier and then to a computer based oscilloscope.
Here is a link of a sample output image taken at 16.7 Hz. The small wave is coming from a signal generator while the larger wave is from the strain gauge and amplified by low noise amplifier.
The signal generator is at 16.7 Hz with a setting of 1.5V per division, while the signal from the strain gauge is a setting of 50 mV per division.
On a different note, the amplifier has a gain based on the resistance value of a particular potentiometer mounted to a circuit board. Is there a way to measure the resistance of that potentiometer while it is mounted to the circuit board? Is it acceptable just to use an ohmmeter across available terminals?
Any help is much appreciated.