Uniden scanning radio Manual page 45

The indicator which
remains on, even if
when there is no
traffic, represents the
frequency being used
as the data channel.
If an indicator turns
on and you don't hear
a conversation, then
the channel is
probably being used
for a telephone
interconnect call or a
private call. These
calls are not
monitored by your
scanner.
The indicator which
flashes when an ID
displays represents
the frequency being
used by the talk
group.
If you're holding on
an ID which isn't
active, the activity
indicators will turn on
and off as other
groups use the
system.
Note: If more than 20 channels are stored in a
bank, then the indicators represent multiple
channels. For example, if 29 channels are
programmed, the first 9 activity indicators each
represent two channels.
45