Sennheiser EM500 Instruction Manual page 8

The EM 500 G3 rack-mount receiver
Each of the channels in the frequency banks "1" to "20" has been factory-
preset to a fixed frequency (frequency preset).
The factory-preset frequencies within one frequency bank are intermodu-
lation-free. These frequencies cannot be changed.
For an overview of the frequency presets, please refer to the supplied
frequency information sheet. Updated versions of the frequency informa-
tion sheet can be downloaded from the EM 500 G3 product page on our
website at www.sennheiser.com.
The frequency banks "U1" to "U6" allow you to freely select and store
frequencies. It might be that these frequencies are not intermodulation-
free (see page 47).
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