Tenda AC1200 User Manual page 117

Wireless AC1200 ADSL2+ Dual Band Modem Router
The best DSL configurations are the factory defaults. Only change them if you are instructed by your ISP or our
technical staff when your router fails to negotiate with ISP in DSL (ATM) mode. Usually, this failure can be identified
and confirmed if the ADSL LED on the device keeps displaying a slow or quick blinking light.
Check the checkbox next to a modulation to enable it and then click Apply/Save.
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Advanced Settings: Click it to enter the Advanced Settings screen as below.
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