You can view the noise spectrum that displays the levels of low frequency (870 Hz - 9 KHz), in-band (9 KHz - 39 KHz), and high frequency noise (39 - KHz - 100 KHz).
Note: Before taking a noise measurement, remove the AC adapter from the
Trex unit, if it is connected. This isolates the Trex unit from the local power
grid.
Note: The spectrum measurement will fail if the noise amplitude exceeds
1.5 V (peak-to-peak). If you see multiple high-amplitude noise peaks, look for
an unattached wire that may cause high noise and saturate the noise detection.