Service manual
Operation GPH Series VHF Radio
Page 3-8
3.4.1 Dual Priority Scan
In each group, up to two of the sixteen 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 the
[PRI]
key is not locked out, the user can move
the channel selector to a new channel and press the
[PRI]
key to choose a new
PR1 channel.
Dual Priority Scan is automatically disabled when Group Scan is on.
3.4.2 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 channel and the transmit channel 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
3.4.2.1 Priority Mode A
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
lights.
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.