FM analog wireless presenter's microphones are a security nightmare...
and an eavesdropper's dream.
Security-wise...
You're naked!
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If you have analog wireless microphones, dump them.
If your A/V company uses them, dump them too, until they upgrade to encrypted wireless microphones.
Replace your info-leakers with one of these digital systems...
• Audio-Technica - SpectraPulse™ Ultra Wideband (UWB)
• Lectrosonics (...and an Encryption White Paper)
• Zaxcom
• Mipro ACT-82
• Telex SAFE-1000
The good news...
Your old wireless system may be eligible for a trade-in!
Most wireless microphone companies are currently offering rebates and free retuning due to changes in the FCC rules. Some are even offering trade-in money. Check here for a partial list of programs.