Cisco VG224 - Analog Phone Gateway Hardware Installation Manual page 32

Chapter 2 Planning Your Installation
Interference Considerations
If you remove any module, you must either install a module in its place or install a cover plate over the
opening. All module openings must be either occupied or covered to prevent electromagnetic
interference.
For advice on the prevention of electromagnetic interference, consult experts in radio-frequency
interference (RFI).
Cisco VG224 Voice Gateway Hardware Installation Guide
2-6
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