DSL filter

A DSL filter is an analog low-pass filter installed on telephones and other analog devices to prevent interference between such devices and Digital Subscriber Line (DSL) service operating on the same line. Without the installation of DSL filters, high-frequency signals or echoes from analog devices can result in reduced performance and connection problems with DSL service, and the high-frequency signals from the DSL service can result in line noise and other issues for analog devices.
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