DMR digital radios: what you gain over analogue

What DMR is

DMR (Digital Mobile Radio) is an open digital standard of ETSI, the European standards body, for business radios. The Motorola MOTOTRBO radios we sell use it. Voice is turned into a digital signal and the channel’s time is shared between two time slots (TDMA), so one 12.5 kHz channel carries two calls at once.

Like analogue radios, DMR radios work on VHF or UHF frequencies assigned by EETT and talk directly to each other or through a repeater for larger areas.

What you gain in practice

Capacity: two groups can talk at the same time on the same frequency, useful when your licence has few frequencies. Battery: in digital mode the radio uses less power, as Motorola’s figures for the DP2400e show (7–12 hours analogue, 10–17 hours digital).

Audio: in digital mode you do not hear signal noise as you do in analogue; near the edge of range the voice drops out instead of filling with static. Features: the DP2600e shows contacts and sends short messages, the DP3441e has GPS, the DP3661e Man Down and Lone Worker, and the R2 basic privacy.

How to move to digital step by step

You do not have to replace every radio at once. New MOTOTRBO radios are programmed with the analogue channels you already use, so they talk to the old fleet from day one. When digital radios are the majority, you switch on digital channels for the groups you choose.

Before you order, send us the details of your licence (band, frequencies, channel width) and of the radios you have. That way we programme the new ones to match and check whether the licence also covers digital operation.

Which DMR radio

For simple use without a display: R2 (UHF, 240 g), DP1400 (VHF, 5 W) and DP2400e. For tough sites: the R5, with IP67 and audio up to 106 phon. For front-of-house staff: SL1600 and SL2600. With a display and many channels: DP2600e, DP3661e and DP4601e. For a vehicle or a desk: DM1400 and DM4600e. For hazardous areas: the ATEX radios DP4401Ex, DP4801Ex and R7Ex.

Coverage and repeaters

A portable radio talks directly to others as far as its signal reaches, which depends on power, terrain and buildings. For larger areas, such as a port or an industrial zone, a repeater on a high point relays calls across the whole area. This applies to analogue and digital radios alike. If your team is spread over several cities, also compare with PoC radios, which need no infrastructure.

Safety for people who work alone

Some digital radios have features our analogue radios lack. The DP3661e has a Man Down sensor, which raises an alarm if the radio stays tilted or falls, and Lone Worker, which raises an alarm if the user does not respond within a set time. Together with GPS, the supervisor knows where to send help.

Vehicles and the office

A digital fleet can also include fixed radios: the DM1400 gives up to 25 W on UHF with a numeric display, and the DM4600e has a colour display, a keypad and a version up to 45 W, on VHF or UHF. They also run analogue and digital channels.