<strong>The Paradox of Part 74: Changes in Wireless Microphones</strong>

The Paradox of Part 74: Changes in Wireless Microphones

December 18, 2017
Wireless Microphones | Electronic Contracting Company

By Dan Balsinger

Many of our customers have asked for additional information about the changes in wireless microphones, and what our options are to reserve channels. For those who don’t know, the Federal Communications Commission (FCC) has auctioned off part of the 600 MHz band. Many wireless microphone users are having to once again pitch the wireless mics they have and buy mics in a new wireless range. The FCC has mandated a transition period, which ends on July 13, 2020. After this period, operation of wireless microphones in the 617-652 MHz and 663-698 MHz frequencies must cease, and even earlier if operations disrupt wireless communications for new service licensees. I’ve included information from RF Venue in this post to help answer some of the questions about these changes.


The Paradox of Part 74

Part 74 licensing was a major theme at each [wireless audio] event I attended, and many speakers and instructors implored audiences to get registered ASAP. But the imposed limits and bureaucracy of even getting setup with FCC Part 74 license protection illustrates the disconnect between what’s been planned and what the world actually looks like. Just look through the 75 steps outlined in this thorough screen by screen guide from IATSE Local 695…  [If you qualify, we recommend contacting one of our AV sales representatives to get licensed instead of doing it yourself.]

The qualifications for getting a Part 74 license include a minimum of 50 channels of wireless used “often” by a professional sound company or large venue operator.

That should cover a lot of production companies and end users, if they follow through an application to approval and submit frequencies to the database. But the vast majority of wireless audio systems in operation are significantly smaller than 50 channels. We ran survey and found that most (in our sample) were 8-16 channels. Should those systems not be afforded license protection? I just heard at the SVG Summit that 50 channel requirement may be relaxed, but we’ll see.

As of this writing there are 1,195 Part 74 licenses that have been issued, up from just a few hundred a couple years ago.

So people are signing up, but not at any kind of rate to see large scale adoption, which is the paradox. Getting Part 74 licensed en masse would afford wireless audio much more consideration at FCC, and yet the requirement limit the number of people who can even get involved right out of the gate.

System design + management

It’s no surprise that solid system design, RF spectrum analysis, and frequency coordination were also highlights at each event. Certain aspects of system design that have not necessarily been a focus in the past seem to be gaining airtime these days. Fixed and tunable bandpass filters, well-designed distributed antenna systems, RF over fiber links, and advanced antenna techniques are among them. What’s encouraging is these tools and techniques greatly improve system performance and are becoming more affordable and easier to use.

The question is, can end users get up to speed and take on these new challenges over the next few years of this transition?

This may well be the biggest challenge ahead. It’s one thing to turn on a mic system, auto-scan it in clear spectrum and walk away. It’s another to invest in spectrum analysis, software, filters, then optimize for SNR with various antenna techniques.

The topic of spectrum efficiency is also a recurring theme. In the past 10 years the new digital wireless systems that have come on the market have had a positive impact on efficiency. Lower power, high density operations are now much more prevalent. That efficiency trend and migration to digital looks like it will continue as analog systems are sunset from some manufacturers’ product roadmaps.

Please reach out to an Electronic Contracting Company AV sales representative to help answer any additional questions on this topic, or set up a site survey to determine the best solution for your wireless needs.