Uniden UBCD396XT Owner's Manual page 185

2. If the tone meets any one of the criteria, the scanner checks to
see if this tone frequency is already saved to a tone out channel
with the same frequency, modulation, and attenuator settings.
3. If the detected tone matches a saved tone, the scanner opens
squelch.
4. If the detected tone does not match any saved tones, the
scanner opens squelch, flashes the tone information on the
display, and asks if you want to save the tone information.
UBCD396XT
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