KX-FT25LA 1 INTRODUCTION 1.1. SAFETY PRECAUTIONS 1. Before servicing, unplug the AC power cord to prevent an electric shock. 2. When replacing parts, use only the manufacturer´s recommended components. 3. Check the condition of the power cord. Replace if wear or damage is evident.
KX-FT25LA 1.6. PERSONAL SAFETY PRECAUTIONS 1.6.1. MOVING SECTIONS OF THE UNIT Be careful not to let your hair, clothes, fingers, accessories, etc., become caught in any moving sections of the unit. The moving sections of the unit are the rollers and a gear. There is a separation roller and a document feed roller which are rotated by the document feed motor.
KX-FT25LA 1.7. FEATURES General · Desktop type · LCD (Liquid Crystal Display) readout · Help function · Copier function · Digital answering system Facsimile · Space Saving Compact Design · Resolution: standard/fine/super fine/halftone · Copier Function · Automatic Document Feeder (10 Sheets) ·...
KX-FT25LA 1.8. SPECIFICATIONS Applicable Lines: Public Switched Telephone Network Document Size: Max. 216 mm (8 1/2”) in width Max. 600 mm (23 5/8”) in length Effective Scanning Width: 208mm (8 3/16”) Recording Paper Size: 216 mm max. 30 m (8 1/2”×98”) roll Effective Printing Width: 208 mm (8 3/16”)
KX-FT25LA 1.13. INSTALLATION 1.13.1. INSTALLING THE RECORDING PAPER Note: Only use the included roll of paper or specified recording paper, or else the print quality may be affected and/or excessive thermal head wear may occur. For accessory order information. When the power cord is connected, every time you close the cover a message will be printed. If the recording paper is set to the wrong side, the message will not be printed.
KX-FT25LA 1.13.4. To select characters with the dial keypad Pressing the dial keys will select a character as shown below. 1.13.5. Documents you can send Note: Remove clips, staples or other similar fastening objects. Check that ink, paste or correction fluid has dried.
KX-FT25LA 1.14. MAINTENANCE ITEMS AND COMPONENT LOCATIONS 1.14.1. OUTLINE MAINTENANCE AND REPAIRS ARE PERFORMED USING THE FOLLOWING STEPS. 1. Periodic maintenance Inspect the equipment periodically and if necessary, clean any contaminated parts. 2. Check for breakdowns Look for problems and consider how they arose.
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KX-FT25LA 1.14.2.1. MAINTENANCE LIST 1.14.2.2. MAINTENANCE CYCLE...
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KX-FT25LA 1.14.3. MAINTENANCE 1.14.3.1. CLEANING THE DOCUMENT FEEDER UNIT If misfeeding occurs frequently or if dirty patterns or black bands appear on a copied or transmitted document, clean the document feeder.
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KX-FT25LA 1.14.3.2. CLEANING THE THERMAL HEAD If dirty patterns or black bands appear on a copied or received document, clean the thermal head. Disconnect the power cord and the telephone line cord. Thermal head Open the cover by pressing the cover open button.
KX-FT25LA 2 TROUBLESHOOTING GUIDE 2.1. TROUBLESHOOTING SUMMARY 2.1.1. TROUBLESHOOTING After confirming the problem by asking the user, troubleshoot according to the instructions and observe the following precautions. 2.1.2. PRECAUTIONS 1. If there is a problem with the print quality or the paper feed, first check if the installation space and the print paper meets the specifications, the paper selection lever/paper thickness lever is set correctly, and the paper is set correctly without any slack.
KX-FT25LA 2.3. TROUBLESHOOTING DETAILS 2.3.1. OUTLINE Troubleshooting guide provides a logical path of deduction to assist in locating a fault and suggests methods of restoring the unit to full working condition. Use the reported symptoms of the fault to determine the best troubleshooting method. Even difficult faults can be tracked to a specific block or area, for example, the "Digital Board"...
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KX-FT25LA 2.3.4.2. Communication Section Find the problem in the table shown below, and refer to the corresponding troubleshooting procedure in 2.3.4.2.1. Defective facsimile section.
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KX-FT25LA 2. Sometimes there is a transmit problem...
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KX-FT25LA 3. Reception problem Confirm the following before starting troubleshooting. Is the recording paper installed properly? There is the receiving problem when sometimes the below errors may be occurred. OUT OF PAPER CHECK COVER Unit OVERHEATED (If it doesn´t return automatically, COVER OPEN, etc., reset the unit.) CHECK DOCUMENT Please refer to 2.2.
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KX-FT25LA 4. The unit can copy, but cannot transmit/receive...
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KX-FT25LA 5. Unit can copy, but cannot transmit/receive long distance or international communications The following 2 causes can be considered for this. Cause 1: The other party is executing automatic dialling, the call has been received by this unit, and the CED or DIS signal response time is too long.
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KX-FT25LA (Causes and Countermeasures) (Cause A) When a training signal is transmitted from FAX1 during the communication procedure at the time of transmission from FAX1 toFAX2, there is a delay until the echo canceler operates. S1 is closed so that a part of the head of the training signal may dropout.
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KX-FT25LA 6. The unit can copy, but the transmission and reception image is incorrect (Long distance or international communication operation) This depends widely on the transmission and reception capability of the other FAX unit and the line conditions. The countermeasures for this unit are shown below.
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KX-FT25LA 7. How to output the Journal Report:...
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KX-FT25LA SND=TRANSMISSION RCV=RECEPTION Most fax communication problems can be resolved by the following steps. a. Change the transmit level. (Service code: 596, refer to 2.4.4. Service Function Table.) b. Change the TX speed/RX speed. (Service code: 717/718, refer to 2.4.4. Service Function Table.)
KX-FT25LA 2.3.4.2.2. Remote programming If, after the call is connected, the customer describes the situation and it is determined that the problem can be corrected by making parameter changes, this function makes it possible to change parameters such as the user code and service code from another fax (using DTMF tones).
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KX-FT25LA 1. Entering the remote programming mode and changing service codes...
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KX-FT25LA 2. Program Mode Table Code Function Set Value Default Remote setting Set the date and time dd/mm/yy hh:mm AM/PM --------- Your logo --------- --------- Your telephone number --------- --------- Print transmission report 1:ERROR 2:ON 3:OFF ERROR Auto receive mode...
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KX-FT25LA Code Function Set Value Default Remote setting Receiving Sensitivity 20~48 Transmit speed select 1:9600/2:7200/3:4800/4:2400bps 9600bps Receive speed select 1:9600/2:7200/3:4800/4:2400bps 9600bps Ringer off in TEL/FAX mode 1:ON/2:OFF Pause tone detect 1:ON/2:OFF Redial tone detect 1:ON/2:OFF CPC mode 1:A / 2:B / 3:OFF...
KX-FT25LA 2.3.4.3. Digital Board Section One of most difficult problems to deal with is when the system will not boot up. The symptom: No response when the power is turned on. (No LCD display, keys are not accepted.) Then first thing to do is check the power source, If there is no problem with the power supply unit, then there is a problem with the digital unit (main board).
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KX-FT25LA 2.3.4.3.1. Digital Block Diagram...
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KX-FT25LA The signal lines that must be normal for the system to boot up are listed here [List 1]. For signal lines other than these, even if they malfunction they do not directly affect booting up the system.
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KX-FT25LA For these reasons and the software sequence to boot up the unit, if you use an oscilloscope to judge whether a signal is OK or NG, you must check in the same order as in [List 1]. (If the ASIC (CPU) failed to access the ROM, the ASIC cannot access the SRAM normally.)
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KX-FT25LA After the power is turned on, the ASIC (CPU) initializes and checks each IC. The ROM, SRAM, and Modem are checked. If initialization fails for the ICs, the system will not boot up.
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KX-FT25LA 2.3.4.3.2. Check the Status of the Digital Board Put the unit in the test mode and check the voltage at lands A, B, C and D.
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KX-FT25LA 2.3.4.4. Analog Board Section The analog parts check is actually different than the digital parts check. The signal route is determined by the purpose of the check. For example, the handset TX route begins from the handset microphone and is output in the telephone line. In this route, it is mainly an analog signal.
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KX-FT25LA Note: { }: Inside the digital board [ ]: Inside the operation board...
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KX-FT25LA 2.3.4.4.2. Defective ITS (Integrated Telephone System) Section...
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KX-FT25LA 2.3.4.4.3. Digital Speakerphone The digital speakerphone has different features from the analog speakerphone. The analog speakerphone switches between Tx or Rx. Either Tx or Rx is able to pass through a telephone line or speaker, depending on the Tx and Rx signal (voice) level. The higher-level signal (either TX or RX) can pass through the route.
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KX-FT25LA Refer to 2.3.4.4. Analog Board Section.
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KX-FT25LA 2.3.4.5. Power Supply Board Section 1. Key components for troubleshooting The following components have been known to break frequently: F101, D101-D104, C109, Q101, PC101, ZD203, R302. This comes from our experience with experimental tests. For example: power supply, lightning surge voltage test, withstanding voltage test, intentional short circuit test, etc.
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KX-FT25LA 3. Broken parts repair details (D101, D102, D103, D104) Check for a short-circuit in terminal 4. If D101, D102, D103 and D104 are short-circuited, F101 will melt (open). In this case, replace all of the parts (D101, D102, D103, D104, F101).
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KX-FT25LA 2.3.4.6. Operation Board Section 1. No key operation 2. No LCD indication...
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KX-FT25LA 2.3.4.7. Sensor Section Refer to 6.5. SENSORS AND SWITCHES for the circuit descriptions. 1. Check the document sensor (PS1)...."CHECK DOCUMENT" 2. Check the read position (PS2)...."REMOVE DOCUMENT"...
KX-FT25LA 2.4. PROGRAMMING AND LISTS The programming functions are used to program the various features and functions of the machine, and to test the machine. Programming can be done in both the on-hook and off-hook conditions. This facilitates communication between the user and the service while programming the machine.
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KX-FT25LA 2.4.3. USER MODE (The list below is an example of the SYSTEM SETUP LIST the unit prints out.) Note: The above values are the default values.
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KX-FT25LA 2.4.4. SERVICE FUNCTION TABLE Code Function Set Value Effective Range Default Remarks Setting the pause time 001~600 X 100 msec 001~600 05000 msec Selects the pause time in 100 msec steps. Setting the flash recall time 01~99 X 10 msec...
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KX-FT25LA Code Function Set Value Effective Range Default Remarks Setting the overseas DIS 1: Detects on the 1st 1, 2 Detects on the Sets the recognition format of the DIS signal. detection time.2: Detects on the 1st time. 1:Detects the first DIS signal sent from the 2nd time.
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KX-FT25LA 2.4.5. SERVICE MODE SETTINGS (Example of a printed out list) Note: The above values are the default values.
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KX-FT25LA 2.4.6. OTHER 2.4.7. SPECIAL SERVICE JOURNAL REPORTS Journal 3 shown below, which are special journals giving the additional detailed information about the latest 35 communications, can be printed by Service Code 882. Remote printing function for the journal reports (JOURNAL and JOURNAL 3) is also available for service technicians.
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KX-FT25LA 2.4.7.1. JOURNAL 3 Descriptions: 1. ENCODE Compression Code: MH/MR 2. MSLT MSLT means Minimum Scan Line Time. Used only at the factory. 3. RESOLUTION (RESOL) Indicates the resolution of the communication. If multiple pages are transmitted or received, it indicates the last page´s resolution.
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KX-FT25LA 2.5.1. DTMF SIGNAL TONE TRANSMIT SELECTION Note: After performing this check, do not forget to turn the setting off. Otherwise, dialing using DTMF will not be possible. 2.5.2. BUTTON CODE TABLE Note: These codes (00, 01) are only for the data in the History Report.
KX-FT25LA 3 ADJUSTMENTS 3.1. ADJUSTING THE FEED PRESSURE If no feeding or multiple feeding occurs frequently, adjust the feeder pressure. 1. Open the front lid by pressing the front lid open. 2. Shift the position of the lever using an instrument with a pointed end, such as paper clip.
KX-FT25LA 5 HOW TO REPLACE THE FLAT PACKAGE IC If you do not have the special tools (for example: SPOT HEATER) to remove the SPOT HEATER´S Flat IC, if you have solder (large amount), a soldering iron, and a cutter knife, you can easily remove the ICs even if there are more than 100 pins.
KX-FT25LA 6.2. GENERAL BLOCK DIAGRAM The control section will be explained as shown in the block diagram. 1. ASIC (IC1) Composed mainly of an address decoder, modem control section, CPU and RTC. Controls the general FAX operations. Controls the operation panel I/F.
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KX-FT25LA 6.2.1. General Block Diagram...
KX-FT25LA 6.3. CONTROL SECTION 6.3.1. BLOCK DIAGRAM...
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KX-FT25LA 6.3.2. ASIC (IC1) This custom IC is used for general FAX operations. 1. CPU This model uses a Z80 equivalent CPU operating at 8MHz. Many of the peripheral functions are handled by custom designed LSIS. As a result, the CPU only needs to process the result.
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KX-FT25LA Pin No. Pin Name Buffer Power Supply Description Digital TONE1 3.3V TONE1 (Analog output) TONE1 TONE2 3.3V TONE2 (Analog output) TONE2 VOLU1 (3.3V) Electronic volume REF for speaker EVOL REF VOLU2 (3.3V) Electronic volume OUT for speaker EVOL OUT VOLU3 (3.3V)
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KX-FT25LA Pin No. Pin Name Buffer Power Supply Description Digital Ground Power supply for buffer RBA0 Bank address (also used as DRAM address) RBA1 Bank address (also used as DRAM address) RBA2 Bank address (also used as DRAM address) RBA3...
KX-FT25LA 6.3.3. ROM (IC2) This 512 KB ROM (OTPROM or MASKROM) has 32 KB of common area and bank area (BK4~BK 63). The capacity of each bank is 8 KB. The addresses of the common area are from 0000H to 7FFFH, and addresses 8000H to 9FFFH are for the bank area.
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KX-FT25LA 6.3.6. SRAM and RTC BACK UP CIRCUIT 1. Function This unit has a lithium battery (BAT1) which works for the RAM (IC4) and Real Time Clock (RTC, Integrated into ASIC:IC1). The user parameter for auto dial numbers, the transmission ID, the system setup date and so on are stored in the RAM (IC4).
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KX-FT25LA 6.3.7. SUPERVISION CIRCUIT FOR THE THERMAL HEAD TEMPERATURE 1. Function The thermistor changes the resistor according to the temperature and uses the thermistor´s characteristics. The output of pin 137 of IC1 becomes a low level. Then when it becomes a high level, it triggers point (A).
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KX-FT25LA 6.3.8. LED ARRAY(CIS) The LED ARRAY will light during transmission and copying as a light source to recognize document characters, patterns, or graphics on a document. It is also possible to light the LED ARRAY in the test mode.
KX-FT25LA 6.4. FACSIMILE SECTION 6.4.1. IMAGE DATA FLOW DURING FACSIMILE OPERATION COPY (Fine, Super-Fine, Half Tone) 1. Line information is read by CIS, via route (1), and is input to IC1. 2. In IC1, the data is adjusted to a suitable level for A/D conversion in the Analog Signal Processing Section, and via route (2) it is input to A/D conversion (8 bit).
KX-FT25LA 6.4.3. THERMAL HEAD 1. Function This unit utilizes state of the art thermal printer technology. The recording paper (roll paper) is chemically processed. When the thermal head contacts this paper it emits heat momentarily, and black dots (appearing like points) are printed on the paper. If this continues, letters and/or diagrams appear, and the original document is reproduced.
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KX-FT25LA 6.4.4. SCANNING BLOCK The scanning block of this device consists of a control circuit and a contact image sensor made up of a celfoc lens array, an LED array, and photoelectric conversion elements. When an original is inserted and the start button pressed, pin 128 of IC1 goes to a high level and the transistor inside IC8 turns on.
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KX-FT25LA 6.4.5. STEPPING MOTOR DRIVE CIRCUIT 1. Function One individual stepping motor is used for transmission and reception. It feeds the document or recording paper synchronized for reading or printing. 2. Circuit Operation During motor drive, gate array IC1 pin 124 becomes a high level, and Q7 and Q5 go ON as a result. +24 V is supplied to the motor coil.
KX-FT25LA 6.4.6. GEAR SECTION This section shows how the motor-driven gear mechanism works in the main operations: FAX transmission, FAX reception the motor and copying. 6.4.6.1. Mode Selection When the motor attached to the Drive Motor Gear rotates counterclockwise (CCW), Swing Gear A-2 engages the CAM and the CAM turns counterclockwise to select a mode.
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KX-FT25LA 6.4.6.2. Mode Operation Once a mode is selected, the Drive Motor Gear rotates clockwise (CW) and then the Swing Gear A-1 controls the mode operation. A: Transmit mode Swing Gear A-1 engages G6 and conveys its drive power to the Separation Roller Gear for pre-feeding documents.
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KX-FT25LA 6.4.6.3.2. Scanning 6.4.6.3.3. Printing Note: See 6.5. SENSERS AND SWITCHES.
KX-FT25LA 6.5. SENSORS AND SWITCHES All of the sensor and switches are shown below. Sensor Circuit Sensor Sensor or Switch Name Message Error Location Digital Motor Position CALL SERVICE 2 Analog Cover Open and Paper set [CHECK COVER] and [OUT OF PAPER] Hook SW ————...
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KX-FT25LA 6.5.1. Motor Position Sensor This sensor is a detection switch for recording the position of the CAM. Digital Board Signal (IC1-119 Pin) Home position Low level Other High level 6.5.2. Recording Paper Sensor (SW1) When there is no recording paper, the plate is separated from the switch lever and the switch turns off.
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KX-FT25LA 6.5.3. Read Position Sensor (PS2) When a document is brought to the read position, the shelter plate passes the sensor light, the photo transistor becomes ON, and the input signal of the CN2-5 pin (Operation) becomes a low level. When there is no document at the read position, the shelter plate closes the sensor light, the photo transistor becomes OFF, and the input signal of the CN2-5 pin (Operation) becomes a high level.
KX-FT25LA 6.6. MODEM SECTION 6.6.1. FUNCTION The unit uses a 1 chip modem (IC5), enabling it to act as an interface between the control section for FAX sending and receiving, and the telephone line. During a sending operation, the digital image signals are modulated and sent to the telephone line. During a receiving operation, the analog image signals which are received via the telephone line are demodulated and converted into digital image signals.
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KX-FT25LA Phase D is the procedure for confirming that the message is completed and received. For continuous transmission, phase B or phase C are repeated for transmission. Phase E : Call retrieval Phase E is the procedure for call retrieval, that is for circuit disconnection.
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KX-FT25LA Explanation of Signals Control signals are comprised mainly of 8-bit identification signals and of the data signals added to them. Data signals are added to DIS and DCS signals. Signal..DIS (Digital Identification Signal) Identification Signal Format..00000001 Function: Notifies the capacity of the receiving unit. The added data signals are as follows.
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KX-FT25LA Bit No. DIS/DTC 17, 18 Recording width capabilities Recording width (0, 0) 1728 picture elements along scan line length of 1728 picture elements along scan line length of 215 mm ± 1% 215 mm ± 1% (0, 1) 1728 picture elements along scan line length of 2432 picture elements along scan line length of 215 mm ±...
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KX-FT25LA Note 2 - Standard facsimile units conforming to T.3 must have the following capability: Index of cooperation (IOC)=264. Note 3 - Standard facsimile units conforming to T.4 must have the following capability: Paper length=297 mm. Signal Identification Signal Format...
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KX-FT25LA b. Redundancy Compression Process Coding Mode This unit uses one-dimensional MH format.
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KX-FT25LA 6.6.2. MODEM CIRCUIT OPERATION The modem (IC5) has all the hardware satisfying the ITU-T standards mentioned previously. When the ASIC IC1 (61) is brought to a low level, the modem (IC5) is chip-selected and the resistors inside IC are selected by the select signals from ASIC (IC1) ADR0-ADR4.
KX-FT25LA 6.8. NCU SECTION 6.8.1. GENERAL This section is the interface between the telephone line. It is composed of bell detection circuit, pulse dialing circuit, CPC detection circuit, line amplifier, sidetone circuits and Remote FAX activation circuit. 6.8.2. Line Relay (RLY1) 1.
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KX-FT25LA 6.8.5. LINE AMPLIFIER AND SIDE TONE CIRCUITS 1. Circuit Operation The reception signal received as output from line transformer T1 is given as input to C14, R13 and IC2(2). Then it is input to the reception system at an amplifier gain of 3.3 dB from pin (2).
KX-FT25LA 6.9. ITS (Integrated telephone System) and MONITOR SECTION 6.9.1. GENERAL The general ITS operation is performed by the special IC5 which has a handset circuit. The alarm tone, the key tone, and the beep are output from the ASIC IC1 (digital board). During the pulse dial operation, the monitor tone is output from the ASIC IC1.
KX-FT25LA 6.11. OPERATION PANEL The unit consists of an LCD (Liquid crystal display), KEYs, photo interrupters (sensor), and analog switches (for key scan). The key scan (analog switch control, reading), sensor detection (sensor control, reading) and LCD control are all controlled by I/O of ASIC (IC1) on the digital board.
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KX-FT25LA 6.11.2. SENSOR DETECTION When CN1(8) (OPSEL) is "L", the detection of the document sensor and read start position sensor are available. 6.11.3. LCD CONTROL "KTXD", "KSCLK", "KLATCH" and "KSTART" are sent as D4~D7 to control the LCD.
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KX-FT25LA Using a different winding ratio results in the voltage function given by the formula in figure (c). As you can see, it is possible to keep VO constant by changing the ratio of TON and TOFF in response to variations in input voltage.
KX-FT25LA 7 FOR THE SCHEMATIC DIAGRAMS Note: 1. DC voltage measurements are taken with an oscilloscope or a tester with a ground. 2. The schematic diagrams and circuit board may be modified at any time with the development of new technology.
KX-FT25LA 8.5. PRINTED CIRCUIT BOARD (SWITCHING POWER SUPPLY) (COMPONENT VIEW) (BOTTOM VIEW) CAUTION SRF912UC FOR CONTINUED PROTECTION AGAINST RISK OF MITSUMI ELEC. CO., LTD. FIRE. REPLACE ONLY WITH 68-4492A SAME TYPE AC125V 5A CN31 7694V-0 AC125V 5A 94V-0 RATINGS OF FUSE.
KX-FT25LA 14 REPLACEMENT PARTS LIST This replacement parts list is for KX-FT25LA only. Ref. Part No. Part Name & Description Remarks Refer to the simplified manual (cover) for other areas. PFJE1009Z LEAD, OPERATION Notes: PFDE1096Z LEVER, DOCUMENT DETECTION PFDE1100Z LEVER, READ DETECTION 1.
KX-FT25LA Ref. Part No. Part Name & Description Remarks Ref. Part No. Part Name & Description Remarks EC10 PFZZ2K2Z CONNECTOR, 2P (TRANSFORMER) T101 ETS29AK415AC TRANSFORMER KM79811245C0 BASIC FACSIMILE TECHNIQUE (VARIABLE RESISTOR) (for training service technicians) VR201 EVNDJAA03B53 VARIABLE RESISTOR Notes: Tools and Extension Cords are useful for servicing.