Two Way Radio General Information
Base Station - A Transmitter / Receiver sited in a fixed location
Battery Options :
Lithium ion (Li-ion)
This is the battery technology used in most mobile phones. Li-ion batteries hold more energy than other batteries of the same weight. They do not suffer from the memory effect that can damage other batteries if charged incorrectly.
NiCad (Nickel Cadmium)
NiMH (Nickel Metal Hydride)
Community Repeater - A repeater base station which is shared by several separate user groups
CTCSS - Continuous Tone Controlled Squelch System. CTCSS codes are sometimes referred to as ‘privacy codes’ as they allow several groups of radio users to make use of the same channel without overhearing the other groups.
dB - Decibel
DTMF - Dual Tone Multi-Frequency
Duplex - Simultaneous two-way sending and receiving
ERP - Effective Radiated Power
FM - Frequency Modulation
Handie-Talkie - Became a trademark of Motorola for a hand portable radio in 1951
Hz (Hertz) – 1 cycle per second
KHz (Kilohertz) - 1,000 cycles per second
MHz (Megahertz) - 1,000,000 cycles per second
Lone Worker - A safety feature that is available on some radios for those who work alone. At pre-set intervals the lone worker will receive an audible alert from his radio to press a button. By pushing the button he is letting his control centre know that he is ok. However should the user continue to ignore the audible alerts then the radio will go into Emergency Mode and alert the control centre accordingly.
Fixed Mobile - Desk mounted radio with power supply and fist or desktop microphone
Man-Down - This is a safety feature available on some radios. A tilt-switch within the radio automatically sends an alarm signal when the radio is tipped on its side for longer than the pre-set period. However the radio will first bleep to alert the user that the alarm signal will be sent if the radio is not repositioned upright. This feature alerts the other radio users to the possibly that the lone worker may have been, for example, overcome by a sudden illness or attacked.
Mobile Radio - Radio installed in a vehicle
Ofcom - Office of Communications - Government organisation responsible for controlling and licensing the use of the airwaves.
PMR446 - This is a UK & European standard for basic, short-range radio that can be sold and used by anyone without the need of a radio license. The radios use the same eight frequencies in the UHF band, around 446MHz, hence the name. The radios can have a maximum power output of 0.5 watts.
PMR - Private Mobile Radio or Professional / Personal Mobile Radio
PTT - Press-To-Talk or (Push-To-Talk) - This is the button on the radio that is held down to make the radio transmit and then released to receive.
RF - Radio Frequency
Repeater Base Unit - Unmanned fixed base unit with external antenna providing enhanced site coverage
RX - Receive
Sellcall - Selective Calling
Semi-Duplex or Half Duplex - This is when you can send and receive, but only one-way at a time, as with a two-way radio. The radio user is unable to interrupt the calling party and must wait until they finish before they can reply
Simplex - A one-way communications channel as used in paging systems
STS - Sequential Tone Signalling
Squelch - Electronic circuitry that mutes the radio speaker and controls the hissing ‘white noise’
TETRA - Terrestrial Trunked Radio
Transceiver - A radio that transmits and receives, the term being created by combining the words ‘transmitter’ and ‘receiver’
Two Way Radio - A term used for any radio that transmits and receives
TX - Transmit
UHF - Ultra High Frequency (400 – 470 MHz) for business radios
VHF - Very High Frequency (136 – 174MHz) for business radios
Walkie Talkie -Is another reference for Two-Way Radio although the original name referred to a back pack radio.
Which is better UHF or VHF?
UHF offers the best coverage and penetration inside buildings or outdoors. VHF is fine in flat open areas or around wood structures.
How much power do I need?
Power is a major factor in achieving the range and coverage in a particular
structure as well as providing a clear, crisp signal that is easy to
understand. Coverage is improved when power is increased.
How many Channels do I need?
One channel per work group is typical. Use multi-channels when separating
multiple workgroups. Examples: Managers, shipping, manufacturing,
maintenance, security, general and sub contractors, different departments
such as stock, customer service, etc.
Do current Motorola radios talk to older models and other brands?
Yes, as long as the frequencies and codes match.
How many two-way radios can be used together?
There is no limit.
How rugged are Motorola two-way radios?
These radios are built rugged for business and meet Motorola's
accelerated life testing including a 5 foot drop to concrete on all sides.