A Guide to Radio Mic

Radio mics — the UK term for what Americans call wireless microphones — use a transmitter at the source and a receiver connected to your sound system to replace the cable between them. For any application where movement matters or cables are impractical, they solve a genuine problem: the performer or speaker can move freely, and the engineer at the desk no longer has to worry about a cable route.

How Radio Mics Work

The transmitter converts the microphone signal into an RF (radio frequency) signal and broadcasts it across a designated frequency band. The receiver picks up the signal, converts it back to audio and passes it to whatever it is connected to — a mixer, camera, recorder or PA system. Most modern systems use UHF frequencies in the 470–960 MHz range, which offer good range and interference resistance compared to older VHF systems.

Better receivers use diversity technology — two antennas — to continuously pick the stronger of two incoming signals. This reduces the dropouts that occur when transmitter and receiver lose line of sight. In professional systems, antenna distribution allows a single pair of receiver antennas to serve multiple channels simultaneously.

Types of Radio Mics

Handheld radio mics combine the microphone capsule and transmitter in a single unit shaped like a conventional vocal mic. The performer holds the unit and sings or speaks into it directly. Handhelds are the standard choice for lead vocalists and presenters who want a familiar-feeling mic in hand.

Bodypack systems separate the microphone from the transmitter. A small transmitter — the bodypack — clips to clothing or a belt and connects via a short cable to a clip-on lavalier (lapel) mic or a headset mic. These are standard for theatre, broadcast, fitness instructors and anyone who needs a mic but cannot hold one.

Instrument transmitters are also bodypack-based. A guitar cable connects the instrument's output to the transmitter, giving guitarists, bassists and other instrumentalists the freedom to move without a cable connecting them to the amplifier or DI box.

UK Frequency Licensing

In the UK, Ofcom regulates radio frequency use, and radio mics operating outside licensed or deregulated bands are illegal. Channel 38 (606–614 MHz) is the most important licence-free band in the UK — systems operating in this range can be used without a licence anywhere in the country. Systems in other UHF bands typically require a shared spectrum licence, particularly for large events. The 800 MHz band (790–862 MHz) was cleared for mobile broadband use from 2012, so equipment designed for that range is no longer usable in the UK.

Always check that any system you buy is specified for current UK frequency allocations before purchase.

Key Specifications

Range is the maximum distance between transmitter and receiver before signal quality degrades. Most consumer and prosumer radio mics specify 50–100 metres in open conditions; professional systems claim up to 300 metres or more. Real-world performance depends heavily on RF environment, obstructions and interference.

Latency — the delay between signal entering the transmitter and reaching the receiver — is effectively zero in analogue systems and a few milliseconds in digital ones. For most applications this is imperceptible; for live monitoring it may be relevant.

Channel count refers to how many simultaneous radio mic systems can operate in a given frequency range. More channels require broader frequency coordination. Professional systems offer wider tuning ranges and better channel management tools.

For those ready to buy, our buyer's guide covers what to look for. For specific recommendations across budgets, see our best for the money guide.

Frequently Asked Questions