Channel 38 vs Channel 70: UK Wireless Microphone Frequency Guide
Key Takeaways
- Channel 38 (606–614 MHz) requires a £85 annual licence but offers 8MHz bandwidth and reduced interference risk for professional applications
- Channel 70 (863–865 MHz) is licence-free but limited to 2MHz bandwidth, 10mW power, and higher interference potential
- UK wireless systems must comply with Ofcom regulations – using Channel 38 without a licence can result in £5,000 fines or imprisonment
- Professional venues and touring crews typically benefit from Channel 38’s licensed protection, while small events may use Channel 70
- Reputable suppliers provide RF scanning, frequency coordination, and fully compliant equipment for both channels
When selecting frequencies for your wireless microphone system, the choice between Channel 38 and Channel 70 can make or break your audio setup. These two specific channels represent the core options available to UK users under Ofcom regulations, each serving different needs and budgets within the programme-making and special events sector.
Understanding the technical differences, legal requirements, and practical implications of each frequency band is crucial for musicians, engineers, churches, small venues, and touring crews operating in the UK. The wrong choice can lead to interference issues, legal penalties, or inadequate coverage for your audio equipment needs.
This comprehensive guide examines both options to help you make an informed decision based on your specific requirements, budget constraints, and technical expertise.
Channel 38 vs Channel 70: The Essential Differences
Aspect | Channel 38 | Channel 70 |
|---|---|---|
Frequency Range | 606–614 MHz | 863–865 MHz |
Bandwidth | 8MHz | 2MHz |
Licensing | Required (£85 annually) | Licence-free |
Maximum Channels | 16-32+ (depending on system) | 4 simultaneous |
Power Output | Higher permitted levels | 10mW handheld, 50mW bodypack |
Interference Protection | Licensed user coordination | No protection guaranteed |
Best for | Professional use, multiple frequencies | Basic applications, budget-conscious users |
The fundamental choice between these two specific channels comes down to balancing cost against performance and reliability. Channel 38 operates as a licensed PMSE frequency band requiring annual fees but providing significantly larger bandwidth and professional-grade reliability. Channel 70 offers licence-free operation but with strict limitations on simultaneous channel usage and no interference protection.
For quick decision-making: choose Channel 38 for professional applications requiring multiple wireless microphones, reliable performance, or touring use. Select Channel 70 for basic applications with 1-4 microphones where budget constraints outweigh performance requirements.
Understanding UK Wireless Microphone Frequency Allocations
The UK’s approach to wireless microphone frequencies operates within Ofcom’s broader PMSE framework, which covers all radio microphones, in-ear monitors, and related audio equipment used in entertainment, broadcast, and events. This regulated approach ensures that multiple frequencies can coexist without harmful interference to tv channels, mobile networks, or other critical services.
Channel 38 and Channel 70 represent carefully planned allocations within the uhf spectrum, designed to provide professional and entry-level options respectively. The 606–614 MHz range (Channel 38) sits within television broadcast frequencies but operates under a shared licence system, while the 863–865 MHz band (Channel 70) functions as a de regulated licence-free zone specifically designated for low-power audio applications.
UK-specific equipment requirements stem from these unique allocations. Wireless microphones designed for US or European markets often operate on completely different frequency ranges that may be illegal in the UK or subject to severe interference from mobile phone networks. The 600 MHz band commonly used in the United States, for example, has been largely allocated to 4G and 5G mobile services in the UK, making American-specification equipment problematic for UK users.
Following the digital dividend process that cleared spectrum for mobile broadband deployment, many traditional PMSE frequencies became unavailable. Channel 69 (854-862 MHz), previously the main licensed band for radio microphones, was withdrawn from PMSE use around 2012. This transition forced the industry to consolidate around Channel 38 as the primary licensed option and Channel 70 as the licence-exempt alternative.
The current allocation provides stability for pmse users while accommodating the spectrum demands of mobile operators and broadcast television. However, ongoing pressure for additional mobile spectrum means that frequency planning remains subject to future regulatory changes, making compliance with current Ofcom requirements essential for all wireless microphone users.
Channel 38: The Licensed Professional Option
Frequency Range and Bandwidth
Channel 38 operates within the 606–614 MHz frequency range, providing approximately 8MHz of usable spectrum for wireless microphones and in-ear monitors. This substantial bandwidth allocation allows for significantly more simultaneous channels compared to licence-exempt alternatives, with professional systems routinely supporting 16, 24, or even 32+ concurrent transmissions when properly coordinated.
The lower uhf frequencies around 600 MHz offer superior propagation characteristics compared to higher frequency bands. This translates to better signal penetration through walls and around obstacles, typically providing 3-5dB improved signal strength compared to Channel 70 systems using identical antenna configurations. For larger venues or challenging RF environments, this propagation advantage can mean the difference between reliable operation and frustrating dropouts.
Professional audio equipment manufacturers design their flagship wireless microphone systems around these frequencies, offering features like automatic frequency coordination, high-resolution frequency scanning, and sophisticated intermodulation avoidance algorithms. The additional frequencies bandwidth permits advanced RF management techniques that are simply impossible within Channel 70’s restricted 2MHz allocation.
Licensing Requirements
Operating wireless equipment on Channel 38 requires an Ofcom uk wireless microphone licence, currently priced at £85 annually (£75 when purchased online). This shared licence covers operation throughout Great Britain but does not provide exclusive frequency access – other licensed users may operate on the same channel in your location.
The licensing system serves multiple purposes beyond revenue collection. Licensed operation provides some interference protection through Ofcom’s coordination procedures, particularly for large events where multiple production companies might otherwise conflict. Licence holders can report interference issues to Ofcom and expect investigation, unlike licence-exempt users who must resolve conflicts independently.
Crucially, operating Channel 38 equipment without appropriate licensing constitutes a criminal offence under UK communications legislation. Penalties can include fines up to £5,000, equipment confiscation, and in extreme cases, imprisonment. For professional users, the annual licence cost represents excellent value compared to the potential legal consequences and performance benefits.
Many professional hire companies hold umbrella licences covering their equipment, providing written permits for client use. This arrangement allows occasional users to access Channel 38 benefits without purchasing their own standard licence, though coordination with the hire company remains essential for legal compliance.
Best Use Cases
Channel 38 excels in professional environments requiring guaranteed audio quality and multiple simultaneous channels. Touring productions benefit enormously from the consistent frequency availability across different venues, eliminating the need to reconfigure systems for each location while maintaining reliable performance standards.
Theatre and concert hall installations typically specify Channel 38 systems for their ability to support complex wireless setups involving multiple handheld microphones, body worn transmitters, and in-ear monitor feeds. The licensed status provides confidence that other users cannot legally interfere with carefully planned frequency coordination.
Corporate events with critical audio requirements – product launches, shareholder meetings, high-profile conferences – justify Channel 38 investment through risk mitigation. The interference protection and professional-grade equipment availability ensure that audio failures won’t compromise important presentations or broadcasts.
Large churches and worship centres increasingly adopt Channel 38 for multi-microphone worship bands, drama productions, and complex audio setups. While the annual licence represents an ongoing cost, the ability to expand beyond four simultaneous channels and the reduced interference risk make this investment worthwhile for active congregations.
Channel 70: The Licence-Free Alternative
Frequency Range and Limitations
Channel 70 occupies the narrow 863–865 MHz band, providing only 2MHz of uhf spectrum for licence-free wireless microphone operation. This restricted bandwidth fundamentally limits the number of simultaneous systems that can operate without harmful intermodulation, with four channels representing the practical maximum for most applications.
The frequency range sits close to mobile phone bands and other communications services, increasing the potential for interference from neighbouring spectrum users. Unlike the licensed Channel 38, Channel 70 users have no recourse when interference occurs – they must simply find alternative frequencies or accept degraded performance.
Intermodulation becomes a critical concern within such limited bandwidth. When multiple transmitters operate simultaneously, their signals can combine to create spurious emissions on usable frequency slots, effectively reducing the available channels below the theoretical maximum. Professional frequency coordination software becomes essential even for the modest four-channel capacity, requiring technical expertise that many small venue operators lack.
The uhf licence exempt range designation means that any compliant device can operate within these frequencies without coordination or notification. This includes not only wireless microphones but also various industrial, scientific, and medical applications that may create unpredictable interference patterns.
Power Restrictions
Channel 70 operation is restricted to 10mW maximum power for handheld transmitters and 50mW for bodypack units. These low power limits reduce transmission range compared to licensed alternatives, typically limiting reliable operation to smaller venues or requiring additional receiver antennas for adequate coverage.
The power restrictions aim to minimize interference between multiple users sharing the same frequency band. However, they also compromise signal reliability in challenging environments such as venues with metal construction, thick walls, or significant RF noise from lighting systems and other electronic equipment.
Battery life in wireless microphones correlates directly with transmitter power output. The reduced power levels in Channel 70 devices can extend battery runtime compared to higher-power licensed systems, though this advantage may be offset by the need for higher RF gain settings to maintain adequate signal levels at the receiver.
Range limitations become particularly problematic for larger venues or outdoor events. While Channel 38 systems might achieve reliable coverage across entire theatre spaces, Channel 70 equipment may require receiver antennas positioned much closer to performers or additional frequency diversity to maintain signal integrity.
Interference Considerations
Channel 70’s licence-free status creates an inherently challenging RF environment with no interference protection from Ofcom. Multiple unrelated users can operate simultaneously in the same location, creating complex interference patterns that change unpredictably as equipment is activated or moved.
Mobile phone networks operating in adjacent bands can create significant interference, particularly in urban environments or venues near cell towers. The proximity of 4G and 5G services around 800 MHz and 900 MHz means that Channel 70 users must contend with high-power licensed services that can easily overwhelm low-power wireless microphone signals.
Cheap imported wireless microphones often operate poorly within frequency specifications, creating spurious emissions that interfere with other users. The licence-free nature of Channel 70 attracts budget equipment manufacturers who may not invest in proper RF design, creating a challenging environment for all users within the band.
Interference mitigation requires constant vigilance and flexible frequency management. Unlike licensed bands where coordination is possible, Channel 70 users must be prepared to change frequencies at short notice when conflicts arise, often during live events when technical adjustments are most problematic.
Which Channel Should You Choose?
For Professional Events and Tours
Professional touring productions should prioritize Channel 38 for its reliability, expanded capacity, and interference protection. The annual licence cost becomes negligible when distributed across multiple events, while the performance benefits prove essential for maintaining professional standards across different venues.
Multi-venue tours benefit enormously from standardized Channel 38 frequency plans that work consistently regardless of location. Professional hire companies can coordinate frequencies across multiple clients and venues, ensuring that touring productions don’t conflict with local installations or other events.
The shared licence system covers operation throughout Great Britain, eliminating the need for venue-specific permissions or local coordination. This simplifies logistics for touring crews while ensuring legal compliance in all locations.
Professional users should invest in equipment from reputable manufacturers offering UK-specific frequency variants. These systems typically include advanced features like automatic frequency coordination, interference detection, and remote monitoring that justify the higher costs through improved reliability and reduced technical labor.
For Churches and Small Venues
Churches with basic audio needs – single pastor microphone, occasional guest speakers – may find Channel 70 adequate for their requirements. The licence-free operation eliminates ongoing costs while providing sufficient capability for simple applications with minimal interference risk.
However, churches planning worship band amplification, drama productions, or multi-microphone events should seriously consider Channel 38. The four-channel limit of Channel 70 becomes restrictive quickly when adding wireless instruments, multiple vocal microphones, and in-ear monitors for musicians.
Growing congregations benefit from the expandability that Channel 38 provides. Starting with a licensed system allows gradual addition of wireless microphones and in-ear monitors without requiring complete system replacement when needs exceed Channel 70’s capacity limitations.
Small venues operating occasional live music or events might use Channel 70 for basic public address requirements. However, venues hosting multiple acts or providing technical services to visiting performers should invest in Channel 38 capability to avoid limiting their programming options.
For Musicians and Engineers
Freelance musicians and sound engineers must consider their typical venue requirements and client expectations. Those working primarily in smaller venues with basic audio requirements might manage with Channel 70 equipment, particularly if budget constraints are significant.
Professional musicians requiring wireless freedom for larger stages or complex performances benefit from Channel 38’s superior range and reliability. The annual licence cost often represents less than the value of a single failed performance due to wireless interference or dropouts.
Sound engineers serving multiple clients should invest in Channel 38 systems for their expanded capabilities and professional credibility. Clients expect reliable wireless performance, and the licensed band provides confidence that technical issues won’t compromise important events.
Equipment investment strategies should consider long-term requirements rather than immediate needs. Channel 38 systems retain higher resale value and provide greater versatility for different applications, making them better investments for professional users planning equipment upgrades.
Working with Professional Suppliers
Professional wireless microphone suppliers provide essential services beyond equipment rental, including RF environment scanning, frequency coordination, and regulatory compliance management. These services prove particularly valuable for Channel 38 systems where proper frequency planning can dramatically improve performance and reliability.
RF scanning identifies existing signals in potential operating frequencies, including TV broadcasts, mobile phone networks, and other wireless microphone systems. Professional suppliers use spectrum analyzers and specialized software to map the local RF environment and select clean frequencies for their equipment.
Frequency coordination becomes critical when multiple wireless systems operate simultaneously. Professional suppliers calculate intermodulation products, plan frequency spacing, and program receivers to avoid conflicts between different systems. This expertise proves invaluable for large events or venues with complex audio requirements.
Equipment quality differs significantly between consumer and professional wireless microphone systems. Professional suppliers stock equipment designed for demanding applications, with features like true frequency diversity, advanced companding algorithms, and robust construction standards that justify higher rental costs through improved reliability.
Technical support capabilities separate professional suppliers from general equipment rental companies. Experienced RF technicians can troubleshoot interference issues, reconfigure systems for changing requirements, and provide on-site support for critical events where audio failure would be unacceptable.
Cost comparisons between purchasing and hiring depend heavily on usage patterns. Occasional users often find professional rental more economical when all associated services are considered, while regular users benefit from equipment ownership combined with professional consultation for complex installations.
Ofcom Compliance and Legal Requirements
Current 2024 regulations maintain the fundamental distinction between licensed Channel 38 and licence-free Channel 70 operation. Recent updates have emphasized enforcement against non-compliant equipment and strengthened penalties for interference to licensed services.
Penalties for non-compliance include fines up to £5,000, equipment confiscation, and potential imprisonment for serious offences. Ofcom’s enforcement teams actively investigate interference reports and conduct market surveillance to identify non-compliant equipment sales.
Record-keeping requirements for Channel 38 licence holders include maintaining logs of equipment serial numbers, operating frequencies, and usage locations. While these requirements aren’t onerous, they demonstrate the professional responsibilities associated with licensed operation.
Reporting interference issues requires understanding the difference between licensed and licence-free user rights. Channel 38 licence holders can demand Ofcom investigation of harmful interference, while Channel 70 users must resolve conflicts through negotiation or frequency changes.
Staying updated with regulatory changes requires monitoring Ofcom announcements and industry communications. Professional suppliers typically provide clients with updates on regulatory changes affecting their equipment, making this another advantage of working with established companies rather than purchasing equipment independently.
Future spectrum planning continues to evolve as mobile operators demand additional frequencies for 5G deployment. While current allocations appear stable, users should be prepared for potential changes requiring equipment upgrades or frequency band migrations over the coming decade.
Frequently Asked Questions
Can I use the same wireless microphone equipment on both Channel 38 and Channel 70?
Many modern wireless microphone systems offer frequency-agile operation covering both Channel 38 (606–614 MHz) and Channel 70 (863–865 MHz) ranges. However, you must ensure your specific equipment model supports the full frequency range and complies with the different power limitations for each band. Additionally, you’ll need the appropriate licence for Channel 38 operation regardless of your equipment’s capabilities.
What should I do if I experience interference on my Channel 70 system during an event?
How does the £85 annual licence fee for Channel 38 compare to the cost of interference problems?
The licence cost represents excellent value when compared to potential losses from audio failures. A single wedding, corporate presentation, or concert ruined by wireless microphone problems could cost far more than the annual fee. Additionally, the licence provides access to larger bandwidth, more simultaneous channels, and Ofcom’s interference protection services.