Vertical Communications and FXT - Manual (Page 115)

Speakerphone Characteristics
When using your speakerphone, the microphone and loudspeaker are farther
away from you than when you use a handset. Both the signal from the
loudspeaker and the signal to the microphone must be strengthened. When
microphones and loudspeakers are close together (such as in a speakerphone),
additional amplification typically generates a ringing sound (public address
systems do this if the volume is too high or the microphone is too close to a
loudspeaker).
NOTE: The 8412F-** speakerphone can function in the full-duplex or
half-duplex mode. Both sets of guidelines are applicable to the 8412F-**.
The 8412S-**, however, can only function in half-duplex mode.
Full-Duplex Speakerphone Guidelines
The Impact SCS 8412F-** speakerphone uses the latest full-duplex speakerphone
technology. (Full-duplex technology enables both parties on a speakerphone call
to speak simultaneously—half-duplex speakerphones carry only one person’s
voice at a time.) The 8412F-** will operate in either full-duplex or half-duplex
mode depending on the current line conditions. For example, satellite calls or
calls with a delay involved may prevent the telephone from operating in
full-duplex mode.
To operate in full-duplex mode, the telephone must perform a “speech training”
test at the beginning of each call. To achieve optimum performance from the
full-duplex speakerphone, Comdial recommends that each user in turn speak
about 10 consecutive words to allow the telephone to “train” itself. Note that
during the “speech training” test, the speakerphone is operating in half-duplex
mode.
Depending on the telephone line conditions and the type of speakerphone at the
other end, it may not be possible for the 8412F-** to operate in full-duplex mode.
If the speakerphone at the other end is a half-duplex speakerphone and both
parties are in speakerphone mode, the half-duplex speakerphone is the
controlling factor, preventing the 8412F-** from operating in full-duplex mode.
Large Screen Display Speakerphone Station User’s Guide 107
GCA70-349 Speakerphone Characteristics
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