The BOTTOM VIEW includes the following:
7) Tone/Pulse switch
This switch us used to select the dialing mode, either TONE (DTMF) or PULSE (Decadic). The correct mode depends on the telephone network.
8) Ringer volume switch
The settings on this switch affects the ringer volume during an incoming call. There are three available ringer volume positions: Low, Medium, and High.
9) Ringer pitch control
The pitch of the ringing sound can be changed by rotating this control on the bottom of the telephone.
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