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Confused about all the technical terms? Don't know your UHF from your VHF? We have compiled a list of technical terms to help you find your way around the world of Radios.
5 Tone (Select 5) Signalling
In 5 tone systems, each radio has a unique numeric identity (e.g. 12345). To signal the number 12345, a sequence of 5 tones is sent. Tone sequences are audible and of short duration. Most 5 tone sequences take less than half a second to send. When the radio receives the correct 5 tone sequence it sounds alert beeps and flashes LEDs to indicate to the user that they have been called. The squelch opens so that activity on the channel can be heard, as this is a message specifically directed at them. Authorisation
This allows the control of call set up and monitoring activity. Only authorised radios have the ability to make calls or monitor channels.
Backlight
Illuminates the radio display, keypad and menu navigation keys.
Call Forward
Allows calls to be forwarded to another radio user.
Call Reminder Alerts
The radio will sound distinctive alerts when an incoming call is not answered. Different indications are provided for individual and group calls.
Call Status Indicators
Audible indications are provided by the radio to indicate the call status, e.g. the called party is busy.
Call Timer
limits the duration of calls. Prior to the call ending, warning indications are given (visual and audible) to inform the callers that the end of the call is imminent so allowing the conversation to be ended.
Carrier Squelch Scan
The radio need only detect a carrier for it to land on a channel and unmute. Scanning just for carrier is the fastest scan method. Channel Alias
To make it easier to recognise the channels, each channel can be given a meaningful alphanumeric name (or Alias) up to 14 characters long.
Contact List
Akin to a phone book - allows access to up to 255 pre-programmed numbers accessed via the menu.
Data Transmissions (GM Series)
The GM300 Series mobiles have been designed to carry data - flat transmit and receive audio available on the accessory connector; special programmable digital lines on the accessory connector; and the ability to connect an internal or external data modem to the radio.
Dedicated Call Buttons
Allows a button to be programmed with a contact number or a pre-programmed (status) message which is dialled whenever the button is pressed.
DTMF
DTMF (Dual Tone Multi Frequency) is used when the radio is required to operate with an interface to a telephone system Dual Power Levels
See High/Low Output Power
Emergency Calls
Pressing a single button establishes immediate communication with a pre-defined person or group of people. Incoming emergency calls are unique and easily identifiable. Emergency calls are prioritised by the radio system.
Escalert
This allows the volume of incoming call indications to steadily increase.
Group Calls
Allows a single user to call a number of other radio users at the same time.
High / Low Output Power
The radio output power can have two settings and these can be varied whilst the radio is being used to conserve power or boost output for greater distance/penetration.
Keypad Lock/Unlock
Allows the keypad keys and menu keys to be locked in order to eliminate accidental key presses.
Low Level Expansion
(LLE)
LLE attempts to remove the noise heard during speech pauses by attenuating the receiver audio. LLE is mutually exclusive with XPand but unlike XPand can be used in mixed fleets of radio products where not all radios have LLE.
Lone Worker
Enables individuals to work alone with added safety by causing the user to press radio buttons on a regular basis. If ignored an emergency signal would be sent.
Low Battery Level Indicator
Audible/visual battery warnings indicate the battery level status - both during calls and on standby.
Memory Channel (GM360/380)
A Memory Channel button has a specific channel assigned to it. A short press of the button will take the radio direct to that channel without having to use the channel scroll buttons or keypad.
Missed Calls List
If an incoming call is unanswered, the caller’s ID will be placed in the Missed Calls List. This details the Caller ’s radio ID, Status digits and Telegram number (advanced multicall users only)
Monitor
Allows voice activity on a channel to be listened to. It is particularly useful in radio systems when a single communication channel is shared by several different teams of people, as it allows individuals to check that the channel is free prior to making a call.
Nuisance Channel
Delete
Allows channels which continually generate unwanted calls or noise to be temporarily removed from the scan list.
Option Board Support
Enhance the functionality through adding an option board for: Voice Storage, SmarTrunk Transcrypt Encryption and Mandown.
Power Off Logic (GM Series)
Enables powering off the radio to be dependent on whether the ignition is on or off and whether the radio is in emergency mode.
Power Off Memory
Certain features are remembered when the radio is turned off, and reinstated when the radio is turned on, including: Channel - (unless there is a designated power up channel), Last selected Address, Last selected Status, Last stored Memory Channel, Backlight ON/OFF, Keypad Tones, ON/OFF, Keypad lock ON/OFF, Escalert ON/OFF, Voice messages, Stun state, Missed calls.
Power Up Channel (GM Series)
The radio can be programmed to power up on a pre-defined channel or the last used channel.
Power Up Logic (GM Series)
The radio can be powered up by: Pressing the on/off switch; starting the radio when the ignition is turned on, turning on the radio in emergency mode when the emergency button is switched on.
Repeater/Talkaround
see Talkaround
Scan Vote
Used in multi-frequency simulcast systems that provide wide area repeater coverage in applications where frequency spectrum is readily available. The typical system has a set of scattered base sites that are transmitting the same information on different frequencies. The radios scan the frequencies of these base sites and perform a voting algorithm to select the strongest base site. The radio’s transmit frequency is typically the same on every channel, but the radio’s receive frequencies are different.
Scanning
Allows activity on different communication channels to be monitored. For the GP or GM series up to sixteen different channels can be put into a scan list which are listened to sequentially. The radio supports up to 16 scan lists.
Squelch Features
Squelch settings are used to keep the radio’s loudspeaker turned off unless the required type of signal is detected.
Status Calls
A status is a code for transmitting prearranged messages of up to 14 alphanumeric characters, e.g. status “05” may indicate “Return to Base”. The prearranged messages and associated code digits are contained in a Status List which contains up to 255 entries. This list is used for both incoming and outgoing calls.
Stun/Un-stun
Disables a stolen radio or a radio being abused by someone not complying with correct communications protocol. Radios can only be unstunned by a signal sent by the system administrator or by reprogramming.
Talkaround
Allows a base station/repeater to be bypassed - it will then be possible to directly contact other radios which are within the normal communication range.
Transmit Admit Criteria
Automatically check the channel for activity and only allow the radio to transmit if certain criteria are Met, including : Never Allowed, Always Allowed, Channel Free, PL/DPL Lockout, Past PL/DPL Lockout Transmit Time-Out Timer (TOT)
Limits the duration of calls by cutting off transmission after a pre-programmed time. Can be cumulative for all calls or non-cumulative.
Voice Recorder
Use as a memo or record incoming calls. Can also send a pre-recorded emergency voice message.
VOX
Works in conjunction with a special VOX headset - enabling calls made by the radio whenever the user speaks into the headset mic. The Mic’s sensitivity can be adjusted to take account of background noise.
Whisper
Allows a user to speak quietly into a radio and still be heard clearly over the air.
XPand
XPand enables background noises to be filtered out by compressing transmit audio and expanding the received audio. If XPand is to be used, ALL members of the team must have this feature engaged. XPand is mutually exclusive with LLE. |
