Wireless RF Compliance Card · AU 2026EasyStagecraft Course · Tier 1B · Module 2 (Speak Sound) · v1.0 · ACMA-compliant frequency bands + the questions you need to ask

Why this matters. Wireless microphones in AU operate under ACMA (Australian Communications and Media Authority) frequency rules. Operating on the wrong frequency = (a) illegal, (b) prone to interference from TV broadcast or police comms, (c) potential prosecution. The supplier should handle this — but you need to ask the right question to confirm they have. This card is the one-page summary.

Section 1 · The legal-to-use frequency bands (AU 2026)

Band	Frequency range	Licence type	Notes
520-694 MHz	UHF Band 4 + lower Band 5	Class Licence (free, no application needed)	The main wireless mic band. Most school-appropriate kit (Shure SLX-D, QLX-D, Sennheiser EW-DX) operates here.
1790-1800 MHz	L-band	Class Licence (free)	Some premium digital systems (e.g. Sennheiser EW-DX in 1G8 variant).
1880-1900 MHz	DECT band	Class Licence (free)	Less common in theatre; some IEM systems.
2.4 GHz ISM	2400-2483.5 MHz	Class Licence (free)	Some consumer + low-end wireless. Heavy WiFi interference — unreliable.

Section 2 · Bands that USED to be available but are NOT now

Frequencies 694-820 MHz were reallocated to mobile carriers in 2014. Equipment operating in this band is now illegal. If a supplier brings in old kit (e.g. Sennheiser EW100 G2 / G3 in the 800 MHz band, or Shure SLX original in the 700 MHz band), it's not legally usable. ACMA can impose fines up to A$13,000 per device per day.

Question to supplier: "Confirm all wireless equipment operates between 520 and 694 MHz, or in another currently-licensed band. Provide the frequency band of each unit in writing."

Section 3 · The Class Licence (no paperwork needed)

The ACMA Radiocommunications (Cordless Microphone Services) Class Licence 2015 permits anyone to operate wireless microphones in the 520-694 MHz UHF band without a licence application or fee, provided the kit is ACMA-compliant. Practically: if the supplier is using kit currently sold in AU, the licence is automatic and free.

If a supplier tries to charge an "RF licence fee" or "ACMA admin fee", challenge it. There is no fee. The Class Licence is free.

Section 4 · The two questions you must ask the supplier

Question	Right answer	Wrong answer
"What frequency band is each unit using?"	"All units are in 520-694 MHz Class Licence band."	"700-800 MHz" — that's illegal. Stop the conversation, refuse the kit.
"Have you coordinated frequencies between units?"	"Yes — we've done a frequency scan + assigned each unit a clean channel. Here's the coordination chart."	"We'll do it on the day" — accept reluctantly but follow up day-of.

Section 5 · Frequency coordination basics

When you run 8 wireless units in the same venue, they need to be on different frequencies — and the frequencies need to be far enough apart not to create "intermodulation" (IM) products that interfere with each other.

The rules:

Each unit on its own clean frequency. No two units on the same MHz value.
Frequencies spaced at intervals that avoid IM products. Modern coordination software (Shure Wireless Workbench, Sennheiser Wireless Systems Manager) handles this automatically.
Avoid local TV broadcast frequencies. Check the ACMA Wireless Microphone Finder tool for your venue location.
Account for venue + city RF environment. A school in regional Mildura has different RF than central Melbourne.

Section 6 · What to expect in a quote for RF coordination

Line item	Reasonable cost	Notes
RF coordination (one-time setup)	A$300-700	Once. Frequencies don't drift between shows.
Per-channel coordination "subscription"	A$0	This is not a real thing.
RF "admin fee" per show	A$0	Not a real thing. Class Licence is free.
Spectrum scan + IM analysis	Included in coordination fee	Should not be a separate line.
Re-coordination during show run	A$0	Frequencies don't drift. If interference appears, that's coordination's fault, not a new charge.

Section 7 · Day-of-show RF checks

On bump-in day, the engineer should perform:

Spectrum scan — to identify any new interference (TV broadcast, other events nearby).
Walk-test — each wireless mic walked through the performance area + checked for dropouts.
Battery check — every body-pack with fresh AA lithium batteries (last 4-6 hours).
Antenna check — antennas positioned for line-of-sight to the stage, not behind metal scenery.

This should take 15-30 minutes. Not "half a day". If the supplier quotes more, ask why.

Section 8 · Common RF issues + what they mean

What you might hear	What it means	Who fixes
"We've got dropouts on channel 4."	Antenna placement issue OR low battery OR frequency contention.	Engineer. ~10-20 min fix.
"Channel 6 has IM products on channel 8."	Coordination missed an intermod relationship.	Engineer. Re-coordinate the affected channels. ~15-30 min.
"The diversity rack is showing low RX."	RF signal weak at receiver — distance, obstruction, or antenna issue.	Engineer. Repositions antenna.
"Local TV broadcast is on our channel 3."	The frequency-scan missed a digital TV broadcaster.	Engineer. Move to clean frequency. ~5 min.
"The pack on Anna is interfering with the pack on Marcus."	The two body-packs are too close together physically, causing RF coupling.	Engineer. Coordinate via spacing or re-frequency.

Reference

For full ACMA wireless microphone information, refer to:

ACMA Wireless Microphones webpage (search "ACMA wireless microphones")
ACMA Wireless Microphone Finder tool (search "ACMA wireless microphone finder")
Radiocommunications (Cordless Microphone Services) Class Licence 2015 (current as of 2026)

Your supplier should be familiar with all of the above. If they aren't, that's a red flag for the supplier-selection conversation.