Oki B4100 - Manual (Page 479)

40055101TH Rev.4 479 /
3-3 TEL-W1 circuit diagram
Note: For each country’s hardware parameter comparison table refer to page A3-88.
1) Speech IC
General functions of the speech IC are as follows:
•
Basic speech functions included.
• Separate receive pre-amplifier with signal output terminal
• Separate receive power amplifier input terminal.
• Balanced input for microphone input to provide immunity to common mode noise.
• MF pre-amplifier input terminal.
• Dial pulse waveform improvement circuit included.
• Manual pad function included.
• The transmit, receive, and DTMF amplifier are provided with AGC in accodance with
the line current.
2) Sending Level Adjustment
The sending level is adjusted by the selection of resistors allocated for individual countries
by the dip-switch settings. The dip-switch set to ON corresponds to the country as shown
in the table below.
• Increase the resistor value to set louder sending level (i.e. lower SLR value).
• Lower the resistor value to set quieter sending level (i.e. higher SLR value).
3) Receiving Level Adjustment
The receiving level is adjusted by the selection of resistors allocated for individual coun-
tries by the dip-switch settings. The dip-switch set to ON correspond to the country as
shown in the table below.
Country Dip-switch Symbol
UK SW3-1 R47
Italy SW3-2 R48
Denmark SW3-3 R55
Norway SW3-4 R56
Belgium SW3-1,4 R47, R56
Country Dip-switch Symbol
UK SW5-1 R35
Italy SW5-2 R36
Denmark/
Belgium
SW5-3 R72
Norway SW5-4 R73
• Lower the resistor value to set louder receiving level (i.e. lower RLR value).
• Increase the resistor value to set quieter receiving level (i.e. higher RLR vallue).