Motorola GM300 Series - Page 32

2-14 FEATURES AND BENEFITS
Carrier Gone Timer Expired – This option only allows transmission when carrier has not been
detected for a programmable period of time.
This option is used to prevent operators currently not involved in calls, transmitting over other users
who may be active on the channel, but are de-keyed with their auto-reset timers running.
PL/DPL Not Detected – This option only allows transmissions when carrier is not present, or
when carrier is present and the radio is not currently detecting the PL decode frequency for the
channel.
This option may be used:
 To prevent PL users in the same group from transmitting over each other;
 If one group is monopolising a repeater, it allows another group to ‘break in’ during
repeater hang time if a PL is also transmitted;
 If used on repeaters that transmit PL during hang times, users from other groups can gain
access during the repeater hang time.
Potential problems are:
 Should not be used on repeaters that transmit PL during repeater hang time as users
within the same group cannot transmit during this period and this leads to enforced gaps
in the conversation.
 A PL user from one group can transmit at the same time as a PL user from another group.
Past PL/DPL Not Detected – This option only allows transmissions when carrier is not present, or
when carrier is present and the radio is not and has not detected the PL decode frequency for the
channel since carrier was detected.
Channel Free or No PL/DPL but Past PL/DPL – This option only allows transmissions when
carrier is not present, or
when carrier is present and the radio is NOT currently detecting the PL decode frequency for the
channel but has detected the PL decode frequency since carrier was detected.
Benefits
 Enforces channel discipline.
 Prevents improper radio transmissions.
 Prevents crosstalk on a shared frequency.
 Equal user access when combined with Time Out Timer.
6.2.1 Transmit Admit Criteria not Applied in Auto Reset
It is possible to disable the Transmit Admit Criteria whilst the radio is in Auto Reset.
Benefits
 Once a call is set up, the user is always able to transmit during the Auto Reset time, this
means they can always finish their call.