Steren TEL-605 Manual De Instrucciones página 35

IF YOU ARE SUBSCRIBER TO A DSL SERVICE (OPTIONAL)
If you receive high speed Internet through your telephone line (commonly
referred as DSL) and you are experiencing interference during conversations,
your caller ID features are not functioning properly, install a DSL filter to the
telephone line between the telephone base and the telephone line jack
(
Steren 300-997).
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