On October 8, 2024, the Federal Communications Commission (FCC) issued an Erratum correcting the Report and Order, FCC 24-22, which was initially released on February 15, 2024. This Erratum pertains to the amendment of Parts 15 and 74 of the FCC’s rules governing wireless microphones, specifically in the following frequency bands:
- TV Bands (54-72 MHz, 76-88 MHz, 174-216 MHz, 470-608 MHz)
- 600 MHz Guard Band (614-617 MHz)
- 600 MHz Duplex Gap (657-663 MHz)
- Other frequency ranges: 941.5-944 MHz, 944-952 MHz, 952.850-956.250 MHz, 956.45-959.85 MHz, 1435-1525 MHz, 6875-6900 MHz, 7100-7125 MHz
The amendment includes changes in emission masks, operating limits, and incorporation by reference of several standards for wireless microphones and multichannel audio systems. These updates impact a range of industries, particularly those utilizing wireless microphones and multichannel audio systems for broadcasting, performance arts, and in-ear monitoring.
Key Changes Introduced by the Erratum
The Erratum replaces Appendix A of the original Report and Order to ensure consistency with the National Archives and Records Administration’s (NARA) standards and publishing conventions. Some of the notable changes include:
- Incorporation by Reference: Various technical standards have been incorporated by reference from organizations like ETSI (European Telecommunications Standards Institute). These standards govern emission masks and operational requirements for wireless microphones operating in different frequency bands.
For example, ETSI EN 300 422-1 V2.2.1 (2021-11) is now referenced for defining emission masks for both analog and digital systems, as well as for Wireless Multichannel Audio Systems.
- Power Limits and Emission Masks:
- For wireless microphones operating in the TV bands, the maximum power allowed is set to 50 mW EIRP for most frequency ranges, while multichannel systems can operate at 100 mW EIRP with a wider bandwidth of up to 1 MHz.
- Emission masks for analog, digital, and wireless multichannel audio systems are clearly defined, ensuring compliance with ETSI standards for both in-band and spurious emissions.
- Operating Frequency and Bandwidth:
- Wireless microphones and multichannel audio systems now have clearly defined bandwidth limits and channelization requirements. Wireless microphones, for example, are restricted to a maximum bandwidth of 200 kHz, while multichannel systems can operate over bandwidths up to 6 MHz in certain bands.
- Spurious Emission Limits: Emissions outside the designated masks must comply with stringent limits outlined in the incorporated standards, ensuring minimal interference with neighboring services.
Importance of the Erratum
This Erratum provides crucial clarifications for those working with wireless audio devices, especially in industries such as broadcasting, theatrical production, concerts, and live events. The rules ensure that wireless microphone operations remain compliant with federal regulations while minimizing interference with television broadcasts and other critical communications services.
For manufacturers and operators of wireless microphone systems, these changes necessitate close attention to equipment specifications and compliance procedures, particularly when designing or utilizing equipment in the newly defined frequency bands.
The FCC has made these updates to accommodate growing wireless microphone use, particularly in crowded spectrum environments, ensuring that audio quality is maintained without disrupting other essential services.
If you need assistance with certification or ensuring your wireless equipment complies with FCC regulations, reach out to our team of experts who can guide you through the approval process. Contact iCertifi today.