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It can be programmed for times up to 7.5 minutes.

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It is reset when the time between transmissions 
exceeds the time programmed for the penalty timer.

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A warning beep sounds 5 seconds before this timer 
disables the transmitter.

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When this timer disables the transmitter, a contin-
uous tone sounds and the red transmit indicator 
turns off. The PTT switch must then be released 
until the penalty timer expires (indicated by a beep).

Normally, all transmissions go through a repeater 

which usually increases range. However, there may be 
times when a user is out of range of the repeater and 
therefore unable to talk to anyone even though the user 
being called is only a short distance away. To allow 
communication in this situation, repeater talk-around 
can be selected. Transmissions then occur on the 
receive frequency which permits direct radio-to-radio 
communication.

Repeater talk-around can be selected if the RTA 

option switch or menu parameter is programmed. 
When talk-around is enabled by this switch, 

 is 

displayed. This feature remains enabled during scan-
ning, and changing channels or turning power off does 
not change the selected condition. Talk-around is 
available on conventional channels only, and power 
output is reduced in this mode.

If the Displayed Information option switch or 

menu parameter is programmed (see Section 4.1), it can 
be used to display the channel frequency in megahertz. 
Pressing this switch toggles between displaying the 
standard channel alias and the channel frequency. The 
receive frequency is displayed when receiving and the 
transmit frequency is displayed when transmitting. This 
feature is available on conventional channels only.

5.10.1  INTRODUCTION

Emergency Alarms and Calls are separate func-

tions that can be individually enabled or disabled on 
each analog and P25 conventional system. The Emer-

gency option switch or menu parameter is required for 
these functions. Emergency Alarms and Calls are 
transmitted on the global (radio wide) emergency 
zone/channel if one is programmed. If it is not 
programmed, the emergency is transmitted on the 
selected channel. The emergency programming of the 
system to which that channel is linked controls the 
emergency operation.

5.10.2  EMERGENCY ALARMS

An emergency alarm is a special transmission that 

alerts a dispatcher of an emergency situation. It is sent 
automatically by simply pressing the Emergency 
option switch or selecting the Emergency menu 
parameter. The system to which the emergency 
channel is linked must have Emergency Alarms 
enabled. If it does not, Emergency Alarms are 
disabled. 

In the P25 conventional mode, a special P25 

emergency data transmission is sent, and in the 
conventional analog mode, an DTMF emergency ID is 
sent. This ID is programmed on the Conventional 
Radio Wide screen. Refer to Section 5.15 for informa-
tion on MDC1200 Emergency Alert.

Proceed as follows to send an emergency alarm: 

1. If required, select a channel of a system on which 

Emergency Alarms are enabled and then press the 
Emergency option switch or select that menu 
parameter. The radio then automatically transmits 
the emergency alarm.

2. Either Normal or Silent operation can be 

programmed. With Normal operation, the red LED 
lights, the emergency tone sounds, and 
“EMERGNCY” flashes in the display. This indica-
tion continues to flash until the alarm mode is ended 
(see step 4). If silent operation is programmed or the 
Surveillance mode is selected (see Section 4.7), 
none of these indications occur. If “No Receive 
Activity During Emergency” is programmed, 
receive audio, the front panel LED, and receive 
icons are disabled in the receive mode.

3. When the emergency alarm is acknowledged by the 

dispatcher, “ACK RCVD” is briefly displayed and 
the emergency acknowledge tone (two beeps)