HP 3390 Service Manual - Page 123

NOTE The all-in-one has not been tested with all of the distinctive-ring services that telephone companies provide in all countries/regions. HP does not guarantee that the distinctive-ring function will operate correctly in all countries/regions. Set up the distinctive ring function 1. Press Menu. Use the < or > button to scroll to Fax setup and then press . 2. Use the < or > button to scroll to Fax recv. setup and then press . 3. Use the < or > button to scroll to Fax recv. setup Answer ring type and then press . 4. Use the < or > button to scroll to one of the following options: ● All rings (default setting) ● Single ● Double ● Triple ● DoubleTriple Press to save the setting. The fax subsystem The formatter, LIU, firmware, and software all contribute to the fax functionality. The designs of the formatter and LIU, along with parameters in the firmware, determine the majority of the regulatory requirements for telephony on the all-in-one. The fax subsystem is designed to support V.34 fax transmission, lower speeds (such as V.17 fax), and older fax machines. Formatter in the fax subsystem The formatter contains the modem chipset (DSP and CODEC) that controls the basic fax functions of tone generation and detection, along with channel control for the fax transmissions. The CODEC and its associated circuitry act to control transmit and receive gains, and to compensate for transmission signal coupling into the receive channel. The formatter also contains circuitry that adds termination impedance to help match the telephone network impedance. LIU in the fax subsystem Two versions of the LIU are used in the HP LaserJet 3390/3392 all-in-one. One is used in the North American, South American, and Asian countries/regions. The other is used primarily in European countries/regions. The following are features that are different in the European version: ● A different voltage-protection device ● Current limiting of the dc current ENWW Fax functions and operation 101