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KX-MB2571RU

The general ITS operation is performed by IC201 which has a handset circuit. The alarm tone, the key tone, and the beep are
output from modem (IC203).

1. Function

This is the function when you are not holding the handset and can hear the caller’s voice from the line.

2. Circuit Operation

(Signal Path)
Signals received from the telephone line are output through at the speaker via the following path.

3. Signal Path

Refer to Check Sheet for Signal Route of MONITER RX (P.175).

1. Function

This circuit monitors various tones, such as (1) DTMF tone, (2) Alarm/Beep/Key tone/Bell.

2. Signal Path

a. DTMF Monitor

(Speaker Operation)
Refer to Check Sheet for Signal Route of DTMF Monitor (Speaker) (P.175).

b. ALARM/BEEP/KEY TONE/BELL

Refer to Check Sheet for Signal Route of MONITER RX (P.175).

1. Function

When TAM is connected to this unit, the unit receives documents for FAX calls or the external TAM records a voice message
automatically.

2. Circuit Operation

The TAM INTERFACE circuit consists of Soc(IC300) to detect the other party CNG signal, and RLY100 to separate EXT.TAM.

a. CNG Signal Detection Circuit

The CNG signal from the other party’s FAX is detected in modem (IC203).
(Signal path)
Refer to Check Sheet for Signal Route of CNG/DTMF detection (P.175).

b. Remote Receiving

This is the parallel-connected DTMF signal for the TEL or EXT.TEL mode between T and R. When the other party is a
FAX, the unit switches to FAX receiving.
(Signal Path)
Refer to Check Sheet for Signal Route of CNG/DTMF detection (P.175).

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KX-MB2571RU

The scanning block of this device consists of a control circuit and a CIS (contact image sensor), and AFE (Analog Front End)
include A/D Converter.

When start the scanning, pin B20 of IC300 will be high level and IC907 turns on, 3.3V is supplied to the CIS. The CIS is driven by
each of the signals (CIS_SP, CIS_CLK, RESOLUTION) which are output from IC300. The analog image signal is input to the AFE
(1,3,5pin of IC700), and converted into 16-bit data by the A/D converter inside. Then this signal undergoes digital processing in
order to obtain a high-quality image in IC300.

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KX-MB2571RU

1. Functions

All driving forces of printer engine part are supplied by this main motor.
Main motor is controlled so as to rotate at constant speed during printing and copying.

2. Motor operation

<Start operation>
In order to start the motor rotation, following 3 signals are supplied from IC300.

1. SS signal (Output pin: Pin U2/Output Signal: "H")
When this signal is inverted by transistor Q521 and becomes "L", motor recognize this signal as "start" signal.
2. Clock signal (Output pin: Pin U1/Output Signal: Pulse)
Pulse frequency :approx. 1.8KHz (at normal printing speed)
Pulse frequency :approx. 0.9KHz.(at half printing speed)
This signal is also inverted by transistor Q522, and supplied to motor as "clock" signal.
3. Brake signal (Output pin: Pin U3/Output Signal: "H")
When this signal is inverted by transistor Q524 and becomes "L", motor recognize this signal as "brake off" signal.

When motor reaches constant speed, "L" signal is supplied from motor to IC300 pin U4 as "Lock detect (LD)" signal.
If "LD" signal does not becomes "L" within predetermined period after "SS" signal becomes "H", or if "LD" signal becomes
"H" during rotation, it is judged that motor Error occurred.

Timing Chart of Start operation

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KX-MB2571RU

<Stop operation>
In order to stop the motor rotation, following 2 signals are supplied from IC300.
1. SS signal (Output pin: Pin U2/Output Signal: "L")
When this signal is inverted by transistor Q521 and becomes "H", motor recognize this signal as "stop" signal.
2. Brake signal (Output pin: Pin U3/Output Signal: "L")
When this signal is inverted by transistor Q524 and becomes "H", motor recognize this signal as "brake on" signal.

Timing Chart of Stop operation