Oki OKIFAX 5400 Maintenance Manual page 335

TELU/TEL-W2/TEL-W1/TEL-W2D/TEL-W2F
3-3 TEL-W1 circuit diagram
Note: Refer to each country's hardware parameter comparison table.
1)
2)
3)
40838301TH Rev.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.
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.
Country
UK
Italy
Denmark
Norway
Belgium
• 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).
Receiving Level Adjustment
The receiving level is adjusted by the selection of resistors allocated for individual
countries by the dip-switch settings. The dip-switch set to ON correspond to the
country as shown in the table below.
Country
UK
Italy
Denmark/
Belgium
Norway
• 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).
Dip-switch Symbol
SW3-1 R47
SW3-2 R48
SW3-3 R55
SW3-4 R56
SW3-1,4 R47, R56
Dip-switch Symbol
SW5-1 R35
SW5-2 R36
SW5-3 R72
SW5-4 R73
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