Whites TDI SL Owner's Manual page 21

TDI SL
Owner's Manual
detectors due to the overwhelming number of EMI sources. If
you cannot minimize noise with the Frequency control, then
turning down the Gain or Threshold is your best bet. Excessive
chatter will easily mask targets, plus results in audio fatigue. It
is better to trade off sensitivity for smooth audio so you can hear
the targets.
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