Operating instructions

Operation DMH Series VHF Radio
BK RADIO Page 3-15
If a message is received on a priority channel, the radio receiver locks on to the
priority channel and checks to see if the proper Channel Guard value is present. If
the signal contains the proper Channel Guard value, the radio receives the message.
Otherwise, the radio will re-check the channel every 4 seconds, until the activity on
the channel ceases.
3.12.1 DUAL PRIORITY SCAN
In each group, up to two of the 16 channels can be designated as priority channels.
These two, PR1 and PR2, are periodically tested for activity, even if a different
transmission is being listened to. Activity on PR2 preempts activity on any of the
non-priority channels. Receptions on PR1 have priority over any other channel in the
group, including PR2.
Either priority channel can be programmed as a fixed channel, tied to the Channel
Selector knob, or programmed OFF. If the radio is programmed to transmit on the
first priority channel, transmissions will occur on PR1 if PR1 isn’t programmed OFF,
when operating in Dual Priority Scan Mode.
If PR1 is a fixed channel, and changes to the 1
st
priority channel are allowed, the
user can move the channel selector to a new channel and press and hold the [PRI]
button for more than 1 second to choose a new PR1 channel.
Dual Priority Scan is automatically disabled when Group Scan is on.
3.12.2 OLD-STYLE BK PRIORITY SCAN
The radio can be programmed with one of three Priority Modes: A, B, or C. The table
below shows how the priority channels and the transmit channels are selected in
each mode.
Mode A Mode B Mode C
Priority Channel Channel Knob Preset Preset
Transmit Channel Channel Knob Channel Knob Priority Channel
3.12.3 PRIORITY MODE A WITH SCAN
In Priority Mode A, the priority channel is set by the Channel Selector knob. Priority
Mode A is seldom used by itself because the radio receives and transmits only on the
knob-selected channel.
When Scan and Priority Mode A are enabled, scanning occurs until an active scan
channel is found. The radio receives the message while continuing to check the
priority (knob-selected) channel. The display shows the scan channel.
If the priority channel becomes active during this message, the Priority indicator
illuminates. The radio changes to the priority channel and holds for the duration of
the message. The display shows the priority channel.
To reply to a message on the priority channel, press the PTT switch and transmit on
the priority channel. Once activity ceases on the priority channel, the radio returns to
scan operation.