Other Problems - Dell 2135cn Service Manual

Chapter 6 Principle of Operation (Fax)

8. Other Problems

Branch Connection (Parallel Connection)
During FAX reception, if the handset of another telephone on a branch connection is lifted, the
received image may be corrupted or a transmission error may occur. Branch connection may also
interfere with caller identification, call waiting, the receiving operation of connected telephones.
Call Waiting
If a call comes in during FAX sending/reception, as with branch connections the image may be
corrupted.
DSL (Digital Subscriber Line)
DSL, a high-speed digital transmission method using existing telephone lines, has several types.
These include ADSL (Asymmetric Digital Subscriber Line) with differing upstream and downstream
transmission speeds, SDSL (Symmetric Digital Subscriber Line) with symmetrical upstream and
downstream transmission speeds, and VDSL (Very high bit rate Digital Subscriber Line) which
features higher speed. However, because the line is used for both voice and data transmission,
various problems may occur, such as noise during spoken conversation, low sound volume, and
mis-dialing. Replacing the splitter may improve the situation.
Noise
If electronic equipment (television, computer, microwave, etc.) or devices equipped with motors are
located near a FAX, noise from them may degrade the line condition.
Also, a telephone line, acting as an antenna, may absorb electric waves generated from wireless or
broadcasting equipment.
Because FAX data is audio data, the line quality affects the quality/stability of image data as well as
that of conversation.
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Version 1 2008.02.01