BROTHER LASER MFC PRINTER – ERROR MESSAGES, HOW TO ENTER THE MAINTENANCE MODE, SERVICE MODE FUNCTION DETAILS

Applicable to Laser printer Brother DCP7055, 7055W, 7057, 7057E, 7057W – DCP 7060D, 7065DN, DCP7070DW/HL, 2280DW – MFC7060, 7060N, 7362N, 7365DN, 7460DN – MFC 7470D. 7860DN, 7860DW

Error messages and codes which the incorporated self-diagnostic
function of the machine will display if any error or malfunction occurs. If any error message appears, refer to this chapter to find which parts should be checked or replaced.

How to Enter the Maintenance Mode

Press the Menu button and then the Start button while the machine is in the ready state.
Next, press the [UP] button four times to enter the maintenance mode.Error codes, 

[Operation using Menu, *, 2, 8, 6 and 4 buttons is also available.]

The machine beeps for one second and displays “ || MAINTENANCE ||| ” on the LCD, indicating that it is placed in the initial state of the maintenance mode, a mode in which the machine is ready to accept entry from the buttons.

To select any of the maintenance mode functions shown below to enter the maintenance mode that you want to use using the buttons.

To exit from the maintenance mode and switch to ready state, press the 9 button twice in the initial state of the maintenance mode.

In the case of the model without the numeric keys; Press the [UP/DN] button. The “MAINTENANCE 99” appears on the LCD. Then press the OK button, and the machine returns to the ready state.

When the Stop/Exit button is pressed, the machine beeps for one second and returns to the initial state of the maintenance mode.

To Enter the End User-accessible Maintenance Mode

Basically, the maintenance-mode functions listed in the next page should be accessed by service personnel only. However, you can allow end users to access some of these under the guidance of service personnel by phone, for example.
The end user-accessible functions are shaded in the table given on the next page. (codes 06, 09, 10, 11, 12, 25, 43, 45, 52, 53, 54, 77, 80, 82, 87, 88 and 91)
Function code 10 accesses the worker switches, each of which has eight selectors.
The service personnel should instruct end users to follow the procedure given below.

Press the Menu, Start, Menu and [UP] buttons in this order when the machine is in the ready state. “MAINTENANCE 06” appears on the LCD.

Press the [UP/DN] button to display the desired maintenance code on the LCD. Then press the OK button.

To switch the machine back to the ready state, press the Stop/Exit button. When each of the user-accessible functions is completed, the machine automatically returns to the ready state.

Maintenance mode functions

EEPROM parameter initialization (Function code 01, 91)

This function initializes the setting values of the operation parameters, user switches, and worker switches (WSW) registered in the EEPROM.

Entering function code 01 initializes almost all of the EEPROM areas, but entering 91 does not initialize some areas, as listed below.

Operating Procedure

Press the 0 and 1 buttons (or the 9 and 1 buttons according to your need) in this order in the initial state of the maintenance mode. In the case of the model without the numeric keys; Press the or button. The “MAINTENANCE 01” appears on the LCD (or the
“MAINTENANCE 91” appears on the LCD to your need). Then press the OK button. The “PARAMETER INIT” appears on the LCD.

Upon completion of parameter initialization, the machine returns to the initial state of the maintenance mode.

Note: Function code 01 is for service personnel. Function code 91 is for user support.

Printout of scanning compensation data (Function code 05)

The machine prints out the brightness level data for scanning compensation.

Be sure to execute this operating procedure not immediately after the power is turned ON, but after conducting the document scanning operation at least once in scanning.
Since the machine initializes the brightness level data and obtains the standard value for document scanning compensation when starting scanning the document, the correct data for compensation cannot be printed out even if this operation is implemented without scanning the document.

The print result varies depending on whether implementing color scanning or black and white scanning immediately before this operating procedure. Make sure the brightness level data you want to print and implement the operation below.

For white and black scanning, copy the document. For color scanning, implement color scanning of the document.

Press the 0 and 5 buttons in this order in the initial state of the maintenance mode. In the case of the model without the numeric keys; Press the [UP/DN] button. The “MAINTENANCE 05” appears on the LCD. Then press the OK button. The “PRINTING”
will appear on the LCD, and the equipment prints out the scanning compensation data list  containing the following:

Black and white/color scanning

[In the case of the black and white scanning, the output data (B) and (R) are invalid.]

LED CURRENT DATA 1 Byte
b) LED pulse data 1(UP) (G) 2 Bytes
c) LED pulse data 1(DOWN) (G) 2 Bytes
d) LED pulse data 1(UP) (B) 2 Bytes
e) LED pulse data 1(DOWN) (B) 2 Bytes
f) LED pulse data 1(UP) (R) 2 Bytes
g) LED pulse data 1(DOWN) (R) 2 Bytes
h) REFH data 1 Bytes
i) Background color compensated data 1 Byte
j) Black level data by previous scanning pixel count
k) White level data (G) by previous scanning pixel count
l) White level data (B) by previous scanning pixel count
m) White level data (R) by previous scanning pixel count.

Placement of scanner unit in position for transportation (Function code 06)

This function is to move the scanner unit in position for transportation located at the left end.
When you fix the machine and check its operation, you need to perform this function last before packing and shipping.

[to perform this function if possible before packing and shipping their FAX machine to a sales agent or a service dealer for the purpose of repair.]

Press the 0 and 6 buttons in this order in the initial state of the maintenance mode. In the case of the model without the numeric keys; Press the [UP/DN] button. The “MAINTENANCE 06” appears on the LCD. Then press the OK button. The scanner unit
moves to the designated position for transportation located at the left end. The “MAINTENANCE 06” is displayed until the scanner unit is placed in position. When the document scanner unit is placed in the position, the “SCAN LOCKED” appears on the LCD.

When the Stop/Exit button is pressed, the machine beeps for one second and returns to the initial state of the maintenance mode.

When the document scanner unit fails to move to the transport position or when the maintenance mode: code 06 is executed while a reading error occurs, “SCAN LOCK ERROR” appears.

After moving the scanner unit to the transport position, you cannot perform the scanning operation such as copy.

ADF performance test (Function code 08)

The machine counts the documents fed by the automatic document feeder (ADF) and counts the scanned document pages and displays the result on the LCD.

Load documents. (Do not exceed the paper capacity of the ADF.) “DOC.READY” is displayed on the LCD.

Press the 0 and 8 buttons in this order.

While counting the documents, the machine feeds them in and out, displaying the number of pages on the LCD as shown below.

ADF CHECK P01 [Current count (1st page in this example)]

When the Stop/Exit button is pressed, the machine beeps for one second and returns to the initial state of the maintenance mode.

Monochrome image quality test pattern (Function code 09)

This function allows you to print various monochrome test patterns and check the quality and if there is any image loss.

Press the 0 and 9 buttons in this order in the initial state of the maintenance mode.
In the case of the model without the numeric keys; Press the [UP/DN] button. The “MAINTENANCE 09” appears on the LCD. Then press the OK button.

Printing of the monochrome image quality test pattern starts, and when printing is finished, the machine beeps for one second and returns to the initial state of the maintenance mode.

Quality test pattern

Worker switch (WSW) setting and printout (Function code 10, 11)

The machine incorporates the following worker switch functions which may be activated with the procedures using the buttons on the control panel. The worker switches have been set at the factory in conformity to the codes of each country. Do not disturb them unless necessary.
Some of these switches are disabled according to the model and specifications.

Press the 1 and 0 buttons in this order in the initial state of the maintenance mode.
In the case of the model without the numeric keys; Press the [up/dn] button. The “MAINTENANCE 10” appears on the LCD. Then press the OK button.
The machine displays “WSW00” on the LCD and becomes ready to accept a worker switch number.

Enter the desired number from the worker switch numbers (01 through 78). The following appears on the LCD. In the case of the model without the numeric keys; Press the [up/dn] button. Select the desired worker switch number.

Enter a value to be set (0 or 1) using the 0 and 1 buttons. In the case of the model without the numeric keys; If press the UP button, it is changed to “1”. And press the DN button, it is changed to “0”. Select the value by this method.

Press the OK button. This operation saves the newly entered selector values onto the EEPROM and readies the machine for accepting a worker switch number.

Repeat steps (2) through (4) until the modification for the desired worker switches is completed.

When the Stop/Exit button is pressed, the machine beeps for one second and returns to the initial state of the maintenance mode.

To cancel this operation and return to the machine to the initial state of the maintenance mode during the above procedure, press the Stop/Exit button.

If there is a pause of more than one minute after a single-digit number is entered for double-digit worker switch numbers, the machine will automatically return to the initial state of the maintenance mode.

Printout of worker switch data (Function code 11)

The machine prints out the setting items of the worker switches and their contents specified.

Press the 1 button twice in the initial state of the maintenance mode. In the case of the model without the numeric keys; Press the [UP/DN] button. The “MAINTENANCE 11” appears on the LCD. Then press the OK button. The “PRINTING” will appear on the LCD.

Printing of CONFIGURATION LIST  starts, and when printing is finished, the machine beeps for one second and returns to the initial state of the maintenance mode.

The function names specific to multi-function machines are printed in CONFIGURATION LIST for convenience of program development. They are invalid in this product and should be ignored.

Operational check of LCD (Function code 12)

This function allows you to check whether the LCD on the control panel works normally.

Press the 1 and 2 buttons in this order in the initial state of the maintenance mode. In the case of the model without the numeric keys; Press the [UP/DN] button. The “MAINTENANCE 12” appears on the LCD. Then press the OK button. The LCD shows.

Each time you press the Start button, the LCD cycles through the displays as shown below.

When the Stop/Exit button is pressed regardless of the display, the machine cancels the operation, beeps for one second and returns to the initial state of the maintenance mode.

Operational check of control panel button (Function code 13)

This function allows you to check if the buttons on the control panel work properly.

Press the 1 and 3 buttons in this order in the initial state of the maintenance mode.
In the case of the model without the numeric keys; Press the [UP/DN] button. The “MAINTENANCE 13” appears on the LCD. Then press the OK button.
The “00” will appear on the LCD.

Press the buttons in the order designated in the illustration shown below. The LCD shows the corresponding number in decimal notation each time a button is pressed.
Check that the displayed number is correct by referring to the illustration below.  When the buttons are pressed in an incorrect order, a warning beep goes off and “INVALID OPERATE” appears on the LCD at the same time. Press the Stop/Exit button, and the press the correct buttons.

After the last number button is pressed, the machine beeps for one second and returns to the initial state of the maintenance mode.

When the Stop/Exit button is pressed, the machine beeps for one second and returns to the initial state of the maintenance mode.

Software version check (Function code 25)

This function allows you to check the management information of the software programs such as version information, check sum.

Press the 2 and 5 buttons in this order in the initial state of the maintenance mode.
In the case of the model without the numeric keys; Press the UP/DN] button. The “MAINTENANCE 25” appears on the LCD. Then press the OK button.
The machine displays each of items described below on the LCD.

Press the [UP/DN] button to check the next item.

When the Stop/Exit button is pressed regardless of the display, the machine cancels the operation, beeps for one second and returns to the initial state of the maintenance mode.

How to display the check sum information
Press the OK button when its version information is displayed on the LCD to display the check sum information. Press the OK button again to go back to the version information display. Press the [UP/DN]button to check the next item.

[Regarding the version information (Network and I-FAX) of which check sum information cannot be obtained, the check sum information is not displayed even if you press the OK button.]

[There are two types of check sum information which can be checked with this function. This function checks if these two types of check sum information are matched each other. When you press the OK button while “ROM Check Sum” is displayed, check is automatically conducted for each ROM of each software part.
When the check sum is matched, “OK” is displayed on the LCD. When all ROMs result in OK, “ROM Check Sum OK” is displayed at the end, and the operation is finished. When the check sum of any ROM is not matched, “NG” is displayed, and the display stops.]

Operational check of sensors (Function code 32)

This function allows you to check each of the sensors.

Press the 3 and 2 buttons in this order in the initial state of the maintenance mode.
In the case of the model without the numeric keys; Press the or button. The “MAINTENANCE 32” appears on the LCD. Then press the OK button.

The machine beeps 1,100 Hz and 400 Hz tones cyclically through the following volumes for testing the speaker. To stop beeping, press the OK button.

If the sensing status are as listed below, the LCD will show “RIRCNTRMRAPOCV_ _”, “DFDRAC” appears on the LCD.
Press the Start button to check the next item.
Given below is the relationship between the LCD indication, sensor name and sensor state.

Sensor locations

VESTEL 17MB18 – LCD TV MAIN BOARD – FUNCTION DETAILS, SERVICE MODE, ALIGNMENTS AND MORE

17MB18 – LCD TV main board – function details, service mode, alignments and more

Many companies are using this board for their LCD TVs.  It is used with 17", 15" and 20" TFT LCD TVs

The system is a 14” to 20” TFT LCD TV solution with UOCIII Versatile Signal Processor and PW1306 Video Image
Processor chip-set on 4-layer PCB. The TV will support PAL/SECAM B/G/D/K/I/L/L’.
The other general default features of the TV are as listed below:
• 1 Full Scart input (with SVHS support)
• 1 SVHS input through standard S-Video interface.
• 1 CVBS input through standard RCA jack
• 75 ohms antenna input
• D-Sub 15 PC Input
• GERMAN + NICAM STEREO
• <3W S/B Power Consumption from mains supply
• 2x3W Speaker Output Power @16 Ohm spks; HP Output, Stereo Audio line out
• Stereo Audio line in
• Equalizer
• IR Control (RC5)
• OSD;Menu Languages ENG, FRA, GER, ITA, SPA, POR, TUR, SWE, DEN, FIN, NOR, POL, HUN, CZE, BUL, ARA, PER, RUS (subject to change and be grouped)
• Teletext
• 2H/4H Comb Filter
• White balance settings (warm/normal/cool) for TV&PC
• Full AIR&CABLE band coverage
• Auto Shut down

17MB18 Main Board consists of two major blocks. The first block is analog front-end and this block is handled by UOCIII chip that is highly multifunctional. This IC does demodulation of Video & Audio from Tuner IF, CVBS, Audio,
RGB, SVHS input selection and processing. It has an audio processor that supports equalizer or tone control, volume control, AVL, surround effect etc and supplies amplifier, headphone and CVBS & audio line outputs. It handles video
processing such as colour standard detection and demodulation, picture alignment (brightness, contrast, colour etc.). The IC also does teletext decoding with 10 pages text memory. After video processing, the processed video is applied to
PW1306 chip in RGB format.
The TV Tuner is an asymmetrical IF output type and is PLL controlled. For multistandard reception, a switchable SAW filter is used as the sound filter and it is controlled by SAW_SW output from UOC. After the SAW filter block, IF signal
is applied to UOC IF inputs (VIFIN[1,2] and SIF[1,2]).
As UOCIII can handle all the audio processing, there is no need for additional audio processor solution on the board.  UOC supports three Audio outputs. These outputs are assigned to Headphone, Speaker and Scart Audio line outputs. The
board employs TDA7056A and TDA1308 to drive speaker and headphone outputs respectively. As another dedicated output for Audio Line out from jack is not possible in UOC, this line out signal is obtained by using I2S input DAC
CS4335. UOCIII I2S output is converted to anolog signal by DAC CS4335.

As the thickness of the TV set has a limit, a horizontal mounted tuner with longer connector is used in the product. The tuning is available through the digitally controlled I2C bus (PLL). Below you will find info on the Asymmetrical Tuner in use.
General description
The tuner meets a wide range of applications. It is a combined VHF, UHF tuner suitable for CCIR systems B/G, H, L, L’, I and I’. The low IF output impedance drives a wide variety of SAW filters with sufficient suppression of triple transient.
Features
Small sized UHF/VHF tuners
Systems CCIR: B/G, H, L, L’, I and I’; OIRT: D/K
Digitally controlled (PLL) tuning via I2C-bus
Off-air channels, S-cable channels and Hyper band
ZS(AE) Aerial source impedance (unbalanced) 75 Ohm

SAW Filters
K3953M is an IF Filter for Video Applications. The package is SIP5K. Supported standards are B/G, D/K, I,L/L’.
K9656M is an IF Filter for Audio Applications. The package is SIP5K. Supported standards are B/G, D/K, I, L/L’.

Back End

The Back End section is handled by PW1306 chip. This IC has built in ADC’s for RGB and SOY support. The RGB input can handle standard interlaced RGB output from UOC, PC VGA RGB input. As only 1 set of ADC is present in PW1306 these sources should be multiplexed.  All the multiplexing operations are controlled by PW1306 via YUV_TV_SW (58) and VGA_TV_SW (57) signals.

The video output from PW1306 is a 48-bit digital RGB bus format and made available on two separate connectors with TTL control signals (i.e. HS, VS, CLK, etc.). This digital output is intended to interface to TTL compatible display
devices. As PW1306 does not have integrated LVDS transmitter, 24 bit (even part of RGB) video output and TTL control signals from PW1306 are also inputted to DS90C385 LVDS IC to produce single pixel LVDS output for LVDS
compatible LCDs.  Backlight control is also possible via PW1306 Porta7 pin (PWMOUT, PL176-10), that is a variable duty-cycle pulse generator output.

Power
Several linear regulators and switches are used to generate several separate analog and digital voltage supplies such as +5, +3.3, +1.8, etc.

UOCIII
The UOCIII series combines the functions of a Video Signal Processor (VSP) together with a FLASH embedded TEXT/Control/Graphics m-Controller (TCG m-Controller) and US Closed Caption decoder. In addition the following functions
can be added:
• Adaptive digital (4H/2H) PAL/NTSC combfilter
• Teletext decoder with 10 page text memory
• Multi-standard stereo decoder
• BTSC stereo decoder
• Digital sound processing circuit
• Digital video processing circuit
The UOC III series consists of the following 3 basic concepts
• Stereo versions. These versions contain the TV processor with a stereo audio selector, the TCG m-Controller, the multistandard stereo or BTSC decoder, the digital sound processing circuit and the digital video processing circuit. Options are the adaptive digital PAL/NTSC comb filter and a teletext decoder with 10 page text memory.
• AV stereo versions. These versions contain the TV processor with stereo audio selector and the TCG m-Controller. Options are the digital sound processing circuit, the digital video processing circuit, the adaptive digital PAL/NTSC comb filter and a teletext decoder with a 10 page text memory.
• Mono sound versions. These versions contain the TV processor with a selector for mono audio signals and the TCG mController. Options are the adaptive digital PAL/NTSC combfilter and a teletext decoder with 10 page text memory.

PW1306
The PW1306 Video Image Processor is a “system-on-a-chip ” that oversamples and processes RGB or YPbPr video from analog video decoders. The PW1306 integrates video processing, including deinterlacer and video enhancement filters with a triple ADC. Analog RGB or YPbPr in PC graphics, standard, or high-definition video can be displayed in either 4:3 or 16:9 formats.
• Supports analog video decoders with triple 8-bit Analog-to-Digital Converters (ADCs) up to 140 MSPS conversion rate
• Supports Sync-on-Green (SOG), Sync-on-Luma (SOY),and Composite sync inputs
• 1080i/720p/480p HDTV; 480i and 576i NTSC/PAL SDTV; PC graphics (up to SXGA)
• YPbPr/YCbCr/YUV-to-RGB Color Space Converter with programmable coefficients
• On-chip, bitmap-based, OSD controller with on-chip memory
• 24/30/48-bit RGB output with 135 MPixels/second maximum output rate.

M29W800AT

Low Voltage Single Supply Flash Memory to store PW1306 code.
ELECTRONIC SIGNATURE
– Manufacturer Code: 20h
– Top Device Code, M29W800AT: D7h

DS90C385
The DS90C385 transmitter converts 28 bits of LVCMOS/ LVTTL data into four LVDS (Low Voltage Differential Signaling) data streams. A phase-locked transmit clock is transmitted in parallel with the data streams over a fifth LVDS link. Every cycle of the transmit clock 28 bits of input data are sampled and transmitted. At a transmit clock frequency of 85 MHz, 24 bits of RGB data and 3 bits of LCD timing and control data (FPLINE, FPFRAME, DRDY) are transmitted at a rate of 595 Mbps per LVDS data channel. Using a 85 MHz clock, the data throughput is 297.5 Mbytes/sec.
• 20 to 85 MHz shift clock support
• Tx power consumption <130 mW (typ) @85MHz Grayscale
• Supports VGA, SVGA, XGA and Dual Pixel SXGA.
• Up to 2.38 Gbps throughput
• Up to 297.5 Megabytes/sec bandwidth
• PLL requires no external components
• Compatible with TIA/EIA-644 LVDS standard.

P15V330
The PI5V330 is a true bidirectional Quad 2-channel multiplexer/demultiplexer that is for both RGB and composite video
switching applications.
• 200 MHz bandwidth
• 3 Ohm on-resistance
• Switching at 10 ns
• 100 mA output current

74HC4052

The 74HC/HCT4052 are dual 4-channel analog multiplexers/demultiplexers with common select logic. Each multiplexer has four independent inputs/outputs (nY0 to nY3) and a common input/output (nZ). The common channel select logics include two digital select inputs (S0 and S1) and an active LOW enable input (E).
• Wide analog input voltage range: ± 5 V.
• Low “ON” resistance.

80 Ohm (typ.) at VCC - VEE = 4.5 V
70 Ohm (typ.) at VCC - VEE = 6.0 V
60 Ohm (typ.) at VCC - VEE = 9.0 V

TA1366FG
TA1366FG is an Analog Y Cb Cr picture signal improver in a 24-pin SSOP plastic package. TA1366FG functions are controlled via I2C bus.
• YCbCr 2inputs
• Through mode (Y bandwidth: 0dB@30MHz)
• Y block
• Sharpness
• SRT (LTI)
• Y Group Delay Correction (Shoot balance)
• Color Detail Enhancer (CDE) and Noise Detection
• Cb/Cr block
• Color SRT (CTI)
• Green Stretcher.

TDA7056A
The TDA7056A is a mono BTL output amplifier with DCvolume control. It is designed for use in TV and monitors.
Mute mode, No switch-on and off clicks,
Thermal protection,
Short-circuit proof,
ESD protected on all pins.

TDA1308

The TDA1308 is an integrated class AB stereo headphone driver contained in an SO8, DIP8 or a TSSOP8 plastic package.
• Wide temperature range
• No switch on/off clicks
• Low power consumption
• Short-circuit resistant

LM1117
The LM1117 is a series of low dropout voltage regulators with a dropout of 1.2V at 800mA of load current. The output voltage can be adjusted..
• Available in 1.8V, 2.5V, 2.85V, 3.3V, 5V, and Adjustable Versions
• Current Limiting and Thermal Protection
• Output Current 800mA
• Line Regulation 0.2% (Max)
• Load Regulation 0.4% (Max)
• Temperature Range
• LM1117 0°C to 125°C
• LM1117I -40°C to 125°C

24LC32
24LC32 is a 4K x 8 (32Kbit) Serial Electrically Erasable PROM capable of operation across a broad voltage range (2.5V to 6.0V).

24LC21
24LC21 is a 128 x 8 bit Electrically Erasable PROM. This device is designed for use in applications requiring storage and serial transmission of configuration and control information.

74LVC541
The 74LVC541A is an octal non-inverting buffer/line driver with 5 V tolerant inputs/outputs. The 3-state outputs are controlled by the output enable inputs OE1and OE2.
5 V tolerant inputs/outputs; for interfacing with 5 V logic
Wide supply voltage range from 2.7 to 3.6 V
CMOS low-power consumption
Direct interface with TTL levels

SAA3010T
The SAA3010 is intended as a general purpose (RC-5) infrared remote control system for use where a low voltage supply and a large debounce time are expected. The device can generate 2048 different commands and utilizes a keyboard with a single pole switch for each key. The commands are arranged so that 32 systems can be addressed, each system containing 64 different commands. The circuit response to legal (one key pressed at a time) and illegal (more than one key pressed at a time) keyboard operation is specified in the section “Keyboard operation”.
Low voltage requirement
Biphase transmission technique
Single pin oscillator
Test mode facility

(I): Input,
(IPU): input with p-channel pull-up transistor,
(ODN): output with open drain n-channel transistor
(OD3): output 3-state

MC34167
The MC34167, MC33167 series are high performance fixed frequency power switching regulators that contain the primary functions required for dc–to–dc converters. This series was specifically designed to be incorporated in step–
down and voltage–inverting configurations with a minimum number of external components and can also be used cost effectively in step–up applications.  These devices consist of an internal temperature compensated reference, fixed frequency oscillator with on–chip timing components, latching pulse width modulator for single pulse metering, high gain error amplifier, and a high current output switch.
Protective features consist of cycle–by–cycle current limiting, under voltage lockout, and thermal shutdown. Also included is a low power standby mode that reduces power supply current to 36 mA.
• Output Switch Current in Excess of 5.0 A
• Fixed Frequency Oscillator (72 kHz) with On–Chip Timing
• Provides 5.05 V Output without External Resistor Divider
• Precision 2% Reference
• 0% to 95% Output Duty Cycle
• Cycle–by–Cycle Current Limiting
• Under voltage Lockout with Hysteresis
• Internal Thermal Shutdown
• Operation from 7.5 V to 40 V
• Standby Mode Reduces Power Supply Current to 36 mA
• Economical 5–Lead TO–220 Package with Two Optional Leadforms
• Also Available in Surface Mount D 2 PAK Package
• Moisture Sensitivity Level (MSL) Equals 1

TFMS5360
The TFMS5360 is a miniature receiver for infrared remote control systems.
• Photo detector and preamplifier in one.
• 36 KHZ
• Pin diode and preamp
• IR filter

UOCIII Service Menu
Turn on the TV.
Press “Menu” (M) and “4” ”7” “2” “5” buttons of RC respectively. The following menu will displayed on the screen.

GTV 3.2.1
000 EurAsia TVSub 05.01
00000000 00111100
01000000 01100100
11000101 01100100
00000000 01100100

Enter register index number directly from RC or use P/CH + and P/CH – buttons in order to go any register setting.
Press Volume + and Volume - buttons of RC in order to change the register value
Press “TV” button from RC in order to turn the UOC service menu off.

Tuner AGC Alignment
In this part, tuner AGC alignment procedure is described.
A TV pattern generator with RF output and volt-meter are needed for this alignment.
Test Set-up
“NICAM Stereo” and 60 dB PAL B/G RF signal from pattern generator will be applied.
Frequency must be set to 224.25 MHz.
• Turn on the TV and measure the AGC voltage from Tuner Pin1 without plugging in any RF input (Around 4.12V).
• Apply “NICAM Stereo” and 60 dB(1 mV) PAL B/G RF signal to the tuner input.
• Enter UOC service menu (as described above), and go to “AGC Take over” setting by pressing “1” “1” “8”.
• Measure AGC voltage from Tuner Pin1. By pressing Volume +/-; adjust AGC voltage so that the measured value at this step should be 0,5V less than the value measured at first step (Around 3.5V).
DCXO Alignment
If this alignment has not properly been done, some front end RF problems can be observed such as Nicam stereo / mono sound switching, low RF reception and color separation performance.
Test Set-up.  This alignment will be performed just after Tuner AGC Alignment. Apply “NICAM Stereo” and 60 dB PAL B/G RF signal from pattern generator. Frequency must be set to 224.25 MHz.
• Turn on the TV.
• Enter UOC service menu (as described above), and go to “DCXO Auto” setting.
• Set “DCXO Auto” value to “1” by pressing “Volume +”.
• TV will automatically align the DCXO (Digital Controlled Xtal Oscillator) value.
• Then TV automatically re-sets “DCXO Auto” value to “0”. This indicates that DCXO Alignment successfully completed.

PW1306 Service Menu
In order to work with PW service menu:
Press “Menu” (M) and “4” ”7” “2” “6” buttons of RC respectively.
Make the desired settings.
Press “Menu” (M) from RC to turn off the PW Service menu.

It is possible to move by using “UP”, “DOWN”, “LEFT” and “RIGHT” RC buttons in this menu structure.

UOC Horizontal Position
Press “DOWN” RC button at “Service Submenu 1” to highlight “UOC Hposition”
Set the proper value to fit the applied pattern to screen by using “LEFT” and ”RIGHT” buttons.

UOC Calibration
Apply 11 Vertical bar Grey-scale pattern with black on the left and white on the right side of the picture(as seen below) from CVBS input.
Press RC “AV” button, and switch to CVBS input and observe the pattern applied.
Enter to PW1306 service menu.
Press RC “DOWN” button at “Service Submenu 1” and highlight “UOC Calibration”.
Press RC “RIGHT” button to start calibration.

PW1306 PC Input ADC Calibration
Connect your TV with your PC and press RC “PC” button and observe the image.
Press “M” to display Menu and select “Options” by using right button of RC.
Press “Down” button of the RC and activate “auto adjustment”.
Press right button of the RC to perform “auto adjustment” and press “M” to exit from Menu.
Apply black on the left, white on the right(as seen below) XGA@60Hz (1024x768) pattern from PC.
Enter PW1306 service menu as described above.
Press RC “DOWN” button at “Service Submenu 1” and highlight “ADC Calibration”.
Press RC “RIGHT” button to start calibration.

NVM initialization

Press RC “RIGHT” button at “Service Submenu 1” and switch to “Service Submenu 2”
Press RC “DOWN” button and highlight “”Init NVM”

Press RC “RIGHT” button to set TV to initial settings. Next time TV is turned on, default settings will be loaded to TV

Initial APS

Press RC “RIGHT” button at “Service Submenu 1” and switch to “Service Submenu 2”
• Press RC “DOWN” button and highlight “”Initial APS”

Press RC “RIGHT” and “LEFT” buttons to set Initial APS to “on” or “off”.(When Initial APS is
to “on” TV will display “Initial APS” menu at first time it is turned ON.

Country
• Press RC “RIGHT” button at “Service Submenu 1” and switch to “Service Submenu 2”
• Press RC “RIGHT” button at “Service Submenu 2” and switch to “Service Submenu 3”Press RC “DOWN” button and highlight ”Country”
• Press RC “RIGHT” and “LEFT” buttons to set the desired country option.

Panel Type Change Shortcut
As 17MB18 software supports from 14” to 20” panel types, it is possible not to see anything on the fault panel type is 15” in the software. That s why, a hidden menu is needed to change supported panel from a hidden menu which is not shown on the screen.

In order to work with PW panel type selection shortcut service menu.

Press “Menu” (M) and “4” ”7” “2” “7” buttons of RC respectively. (Caution! No visual menu appear on the screen)

Press individual panel type selection digit to select the panel.

Turn off the TV from RC.

When the TV turns on again, it will come with new panel settings.

0 > 15” Samsung

1 > 20” CMO

2 > 17” LG

SETTINGS AND FACTORY DEFAULTS

Creating Master EEPROM

• Load the new SW version to the TV.
• Place empty EEPROM to IC101 position of the mainboard.
• Turn on the TV.SW will automatically assign the initial values to the EEPROM.
• Adjust the settings of Service Menu and User Menu.
• This EEPROM can be used as Master EEPROM.

Creating Mass Production EEPROM
• The Master EEPROM prepared like above is copied and multiplied to use in mass production.
• The copy EEPROM is placed on IC 101 of 17MB18. (When TV is turned on the software will realise that EEPROM is not empty, so SW will not change the values in the EEPROM.)

Brightness and contrast values will be left unchanged after the UOC Calibration.
xx Tint value is determined automatically by software and is active in only NTSC channels. So there is no need to adjust any value in this section.

SHARP 21LT 45SES HOW TO ENTER THE SERVICE MODE, DEFAULT DATA VALUES, AND ALL DETAILS OF VESTEL 11AK44 CHASSIS

PAL B/G / SECAM L/L’, B/G, D/K SYSTEM COLOUR TELEVISION: AK-44 Chassis

Vestel 11AK44 is a 90° chassis capable of driving 20"/21" tubes at the appropriate currents. The chassis is capable of operating in PAL, SECAM and NTSC standards. The sound system is capable of giving 4 watts RMS output into a load of 16 ohms.

The chassis in this receiver is partially hot. Use an isolation transformer between the line cord plug and power receptacle, when servicing this chassis.

White Level
Apply the rated voltage at the rated frequency to the TV set, while it is receiving full white pattern RF signal of 60 dB/µV from its RF input via the pattern generator.
Turn all picture controls to maximum value. Measure the colour temperatures at the center of the screen by using the colour analyzer.
X=0.290 ± 0.015 Y=0.300 ± 0.015

It is important that the static charge is removed from the high voltage system when carrying out work on the receiver. This can be achieved by connecting a 10K resistor (with a suitably insulated lead) from the CRT cavity connector to the CRT ground tag. This must be carried out with the AC supply disconnected from the receiver.

DO NOT increase the EHT to more than 29.5 KV, (at a instantaneous beam current of 1150 µA

This level has been preset in the factory. Always check that this level has not been exceeded after carrying out any repair on the receiver.

To update the Technical Information

Web site: https://www.vestelservice.com
Select: Technical Support
Login: 101278
Password: SHPII278

By this access you can consult the latest schematic diagram or request the Parts Listing of a concrete Production Date / Serial Number.

PERI-TV SOCKET connections detail

Vision IF amplifier
The vision IF amplifier can demodulate signals with positive and negative modulation. The PLL demodulator is completely alignment-free. Although the VCO (Toko-coil) of the PLL circuit is external, yet the frequency is fixed to the required value by the original manufacturer thus the Toko-coil does not need to be adjusted manually. The setting of the various frequencies (38.9 or 33,8 MHz) can be made via changing the coil itself.

QSS Sound circuit (QSS versions)
The sound IF amplifier is similar to the vision IF amplifier and has an external AGC de-coupling capacitor. The single reference QSS mixer is realised by a multiplier. In this multiplier the SIF signal is converted to the inter-carrier frequency by mixing it with the regenerated picture carrier from the VCO. The mixer output signal is supplied to the output via a high-pass filter for attenuation of the residual video signals. With this system a high performance hi-fi stereo sound processing can be achieved. The AM sound demodulator is realized by a multiplier. The modulated sound IF signal is multiplied in phase with the limited SIF signal. The demodulator output signal is supplied to the output via a low-pass filter for attenuation of the carrier harmonics. The AM signal is supplied to the output via the volume control.

FM demodulator and audio amplifier (mono versions) The FM demodulator is realized as narrow-band PLL with external loop filter, which provides the necessary selectivity without using an external band-pass filter. To obtain a good selectivity a linear phase detector and constant input signal amplitude are required. For this reason the inter-carrier signal is internally supplied to the demodulator via a gain controlled amplifier and AGC circuit. The nominal frequency of the demodulator is tuned to the required frequency (4.5/ 5.5/6.0/6.5 MHz) by means of a calibration circuit that uses the clock frequency of the µ-controller/Teletext decoder as a reference. The setting to the wanted frequency is realized by means of the software. It can be read whether the PLL frequency is inside or outside the window and whether the PLL is in lock or not. With this information it is possible to make an automatic search system for the incoming sound frequency. This is realized by means of a software loop that alternate the demodulator to various frequencies, then select the frequency on which a lock condition has been found. De-emphasis output signal amplitude is independent of the TV standard and has the same value for a frequency deviation of ±25 kHz at the 4.5 MHz standard and for a deviation of ±50 kHz for the other standards. When the IF circuit is switched to positive modulation the internal signal on de-emphasis pin is automatically muted. The audio control circuit contains an audio switch and volume control. In the mono inter-carrier sound versions the Automatic Volume Levelling (AVL) function can be activated. The pin to which the external capacitor has to be connected depends on the IC version. For the 90° types the capacitor is connected to the EW output pin (pin 20). When the AVL is active it automatically stabilises the audio output signal to a certain level.

Synchronisation circuit
The video processor (STV224X) performs the horizontal and vertical processing. The external horizontal deflection circuit is controlled via the Horizontal output pulse (HOUT). The vertical scanning is performed through an external ramp generator and a vertical power amplifier IC controlled by the Vertical output pulse (VOUT).
The main components of the deflection circuit are:
• PLL1: the first phase locked loop that locks the internal line frequency reference on the CVBS input signal. It is composed of an integrated VCO (12 MHz) that requires the chroma Reference frequency (4.43 MHz or 3.58 MHz crystal oscillator reference signal), a divider by 768, a line decoder, and a phase comparator.
• PLL2: The second phase locked loop that controls the phase of the horizontal output (Compensation of horizontal deflection transistor storage time variation). Also the horizontal position adjustment is also performed in PLL2.
• A vertical pulse extractor.
• A vertical countdown system to generate all vertical windows (vertical synchronization window, frame blanking pulses, 50/60 Hz identification window...).
• Automatic identification of 50/60 Hz scanning.
• PLL1 time constant control.
• Noise detector, video identification circuits, and horizontal coincidence detector.
• Vertical output stage including de-interlace function, vertical position control.
• Vertical amplitude control voltage output (combined with chroma reference output and Xtal 1 indication).

Chroma and luminance processing
The chroma decoder is able to demodulate PAL, NTSC and SECAM signals.
The decoder dedicated to PAL and NTSC sub-carrier is based on a synchronous demodulator, and an Xtal PLL locked on the phase reference signal (burst).
The SECAM demodulation is based on a PLL with automatic calibration loop.
The color standard identification is based on the burst recognition.
Automatic and forced modes can be selected through the I2C bus.
NTSC tint, and auto flesh are controlled through I2C bus.
Xtal PLL can handle up to 3 crystals to work in PAL M, PAL N and NTSC M for South America.
ACC an ACC overload control the chroma sub-carrier amplitude within 26dB range. Both ACCs are based on digital systems and do not need external capacitor.
All chroma filters are fully integrated and tuned via a PLL locked on Xtal VCO signal.
A second PLL is used for accurate fine-tuning of the SECAM bell filter. This tuning is achieved during the frame blanking.
An external capacitor memorizes the bell filter tuning voltage.
A base-band chroma delay-line rebuilds the missing color line in SECAM and removes transmission phase errors in PAL.
The base-band chroma delay line is clocked with 6 MHz signal provided by the horizontal scanning VCO.
The luminance processor is composed of a chroma trap filter, a luminance delay line, a peaking function with noise coring feature, a black stretch circuit.
Trap filter and luminance delay lines are achieved with the use of bi-quad integrated filters, auto aligned via a master filter phase locked loop.

µ-Controller
The ST92195 is the micro-controller, which is required for a color TV receiver. ST92195D1 is the version with one page Teletext and ST92195D7 is the one with 7 page Teletext. The IC has the supply voltage of 5 V and they are mounted in PSDIP package with 56 pins.
µ-Controller has the following features
- Display of the program number, channel number, TV Standard, analogue values, sleep timer, parental control and mute is done by OSD
- Single LED for stand-by and on mode indication
- System configuration with service mode
- 3 level logic output for SECAM and Tuner band switching
IC 501 controls all the functions of the receiver operated by the remote control and the front panel customer controls. It produces the on screen graphics, operates tuning, customers controls and engineering controls, and also incorporates all of the Teletext functions. It also controls the video processor, the audio processor, and the tuner. The circuits just mentioned are controlled via the I²C bus. Also IC501 controls the video source switching, vertical position adjustment and the vertical linearity adjustment via its ports.
An external 8K EEPROM is used by the micro. The EEPROM comes fully programmed. The main clock oscillator is 4.0 MHz crystal X501 on pins 50 and 51. Reset is provided on pin 2 via Q504. On switching on pin 2 becomes high and the controller gets reset which stays valid till a low signal comes on that pin.
Controls
Command information from the infrared remote controller is fed through the sensor IC502 to pin 1 of the microprocessor. Operation of the customer front panel keys is detected by pin 8 that is an ADC (analogue to digital converter). Pressing a switch will connect the 5V to the ground through a particular resistor that determines the value of the voltage on pin8 at that instant. This obtained value is comprehended by the micro and the corresponding operation is performed.

IC501 automatically switches from TV mode to AV1 by detecting the signal from or pin8 at the Scart connector, through it 56 pins.

Teletext
The microprocessor IC501 performs all of the Teletext functions internally. The Composite blanking video and Sync signal (CBVS) is input to pin 33 of the micro from pin 29 of IC403. When text is selected the text graphics are output as R.G.B signals on pins 15/16/17 of the micro and fed to pins 34/35/36 of IC403. At the same time pin 18 of the micro goes high taking pin 37 of IC403 high, blanking the picture and selecting text R.G.B. input.
Note: mixed mode is available and fast text with 8-page memory.

Video Path
The detected video signal is output from pins 18 of IC403, to sound traps Z403/404. The video is taken from the other side via the appropriate filter to Pin 18 of IC403. (1.2 p to p) Video to the Scart connectors is taken after R458 to Pin 19 of the Scart connector. The CVBS_TXT output Pin29 output is fed to IC501 Pin 34 (for Teletext). The video signal is sometimes labelled CVBS on the circuit diagram. This stands for Composite Video Blanking & Sync.
The composite signal is input Pin 13 (Video input) of IC403. This IC carries out all of the luma/Chroma processing internally and also provides the customer control functions of brightness, contrast, sharpness and saturation. IC403 is I²C bus controlled and incorporates auto grayscale circuitry and internal luma/chroma delay lines. The resulting R.G.B drive is output on pins 30,31 and 32. The R.G.B passes via connector PL405 to the CRT base PCB. Here the R.G.B signal is amplified by IC901 to provide drive for the cathodes of the CRT. IC901 produces a feedback signal, which is fed to IC403 (pin 33) for blanking and auto grayscale correction.

Sound Path
The demodulated mono sound is taken from pin 55 of IC403 directly to the sound output stage IC401 Pin 7. The output signal from IC401 is Volume controlled achieved within IC403 using the I²C bus line from IC501. To limit the volume at the specified out put the A_out pin 55 is fed to IC 401 through a voltage divider R455 and R454. Muting of the output stage is provided from Pin 46 of IC501 to pin3 of IC401/6 of IC301.
IN the stereo model the IF from PINS 10 & 11 of the tuner passes through Z401 and the output signal goes through pins 1&2 of IC403. The output QSS signal from IC 403 is taken from pin 11 and sent to audio processor IC700. The left channel is output on PIN 29 and the right channel output is on PIN 28. Then to IC301 after passing through a voltage divider R454/R455 for the right channel and R463/R464 for the left channel.
IC403 handles also the AM modulated signals in L/L’ systems at pins 1&2.

DIGITAL TV sound processor MSP34X0
The MSP 34x0G is designed to perform demodulation of FM or AM-Mono TV sound.
Alternatively, two-carrier FM systems according to the German or Korean terrestrial specs or the satellite specs can be processed with the MSP 34x0G. Only the MSP 3410 does digital demodulation and decoding of NICAM-coded TV stereo sound. The MSP 34x0G offers a powerful feature to calculate the carrier field strength which can be used for automatic standard detection (terrestrial) and search algorithms (satellite).

Sound output stage TDA7266L/TDA7266
TDA7266L is used as the AF output amplifier for mono applications. It is supplied by +12 VDC coming from a separate winding in the SMPS transformer. An output power of 4 W (THD = 0.5 %) can be delivered into an 16 ohm load.
TDA7266 is used as the AF output amplifier for stereo applications. It is supplied by +12 VDC coming from a separate winding in the SMPS transformer. An output power of 2*4W (THD = 0.5 %) can be delivered into an 16 ohm load.

Vertical output stage - TDA8174A
The TDA8174A is a power amplifier circuit for use in 90° and 110° color deflection systems for 25 to 200 Hz field frequencies, and for 4 : 3 and 16 : 9 picture tubes.
IC403 generates a vertical pulse signal VER_OUT and V_AMP that are fed to IC600 (the vertical stage IC). IC600 is supplied by a 26V DC via diode D610. It generates its own ramp signal and based on the V_AMP & VER_OUT signals it produces the vertical deflection signals that are fed to connector PL601. Vertical linearity adjustment is controlled by Q604, which is driven by the PWM output of IC501 at pin 49. Vertical position adjustment is conducted by Q606 derived by the VER_OUT signal. Switching Q606 will change the DC voltage on VOUT_2 pin, which will either lower or higher the picture. A DC level is supplied at VOUT_2 via D614 to stabilize the picture and make its position changeable.

Power supply (SMPS)
The DC voltage required at various parts of the chassis are provided by an SMPS transformer controlled by the IC MC44608 which is designed for driving, controlling and protecting switching transistor of SMPS. The transformer produces 126 V (Flat models) or 116 V (non Flat models) for FBT input, +/- 14 V for audio output IC, S + 3.3, S + 5 V and 8 V for ST92195.
The ZX series of receivers incorporate a Motorola switch mode power supply using a MC 44608 regulator controller IC. The circuit provides power to the receiver in both standby and normal operation modes.

Start Up
The switch on the mains supply is fed through the mains filter network TR801, the surge limiter resistor R828, the bridge rectifier diodes D811/13/37/38, and reservoir capacitor producing approx. 320 volts D.C. to feed the switching MOSFET Q801 via the primary winding of TR802 pins 6 and 7.
Start up resistor R801 feeds from a 500V coming from the mains through the adder diodes D809, D890 to pin 8 of IC800, the IC uses 9mA current source and connects it internally to VCC at pin6 allowing a rapid charge enough for start up. Then IC800 responds with the oscillator starting to oscillate at a 40 KHz frequency fixed by the IC manufacturer.
The IC then produces, pulse width modulation pulses, at this frequency on pin 5 to drive the base of the switching FET Q801, that will then switch current on and off through the primary of TR802, which will in turn provides voltages in the secondary windings. The secondary winding voltages being proportional to the length of time that Q801 is turned on in each cycle. The voltage produced between pins 4 and 3 of TR802 is rectified by D804 developing aprox. 12 volts on C810, which takes over from the start up resistor to supply pin 8 of IC800.
The Demag pin at pin1 offers 3 different functions: Zero voltage crossing detection (50mV), 24mA current detection and 120mA current detection. The 24mA level is used to detect the secondary reconfiguration status and the 120mA level to detect an Over Voltage status called Quick OVP.
The VCC at pin6 operates between 6,6V and 13V in normal operation, when this voltage exceeds 15V then the IC output is disabled.

Voltage Regulation
After initial start up the secondary voltages of TR802 are established. These voltages then need to be regulated to the required levels. In a switch mode power supply such as this, it is the ON time of the switching FET Q801 that determines the output voltages produced. To provide regulation of the supply there is a feedback loop via an adjustable zener IC118 and an OPTO- coupler connected to pin3 of IC800. The reference voltage of IC118 is set to 2,5V to supply a B+ voltage of 115V. Any fluctuation at this pin will cause IC800 to compensate it either by increasing or decreasing the voltage at the secondary outputs.

Voltage Protection
The MC44608 offers two OVP functions:
1- A fixed function that detects when V CC is higher than 15.4V
2- A programmable function that uses the demag pin. The current flowing into the demag pin is mirrored and compared to the reference current Iovp (120mA). -Thus this OVP is quicker than normal number one as it directly senses the change in current rather than waiting for a specific voltage value, and is called QOVP. In both cases, once an OVP condition is detected, the output is latched off until a new circuit START–UP.
3- A software controlled function acts on pin52 of IC501. This pin monitors feedback from both 8V and 5V via D512, then compares these to a reference value Vref pre-set by the hardware through resistors R545, R546, R548. In normal mode operation 1.2V < Vref < 2.4V. Any voltage outside this window will cause the micro controller to force the TV to stand by mode by lowering the standby port. Refer to standby mode.

Current Protection
To monitor the current drawn by the receiver the source of Q801 is returned to the bridge rectifier through a low value resistor R807. All the current drawn by the receiver will flow through that resistor each time Q801 conducts; this will produce a voltage across the resistors proportional to the current drawn by the receiver. This voltage is fed to pin 2 of IC800 via R806. When the receiver is working normally the voltage across R807 is only a fraction of a volt and is not large enough to have any effect on IC800. Under fault conditions, if the receiver draws excessive current the voltage across R807 will rise. This voltage is monitored by the current sense input pin2.

This Current Sense pin senses the voltage developed on the series resistor R806 inserted in the source of the power MOSFET. When I sense reaches 1V, the Driver output (pin 5) is disabled. This is known as the Over Current Protection function. A 200mA current source is flowing out of the pin 3 during the start–up phase and during the switching phase in case of the Pulsed Mode of operation. A resistor can be inserted between the sense resistor and the pin 3, thus a programmable peak current detection can be performed during the SMPS stand–by mode.

Standby Operation
As mentioned earlier the Start–up Management of MC44608 is as follows:
The Vi pin 8 of IC800 is directly connected to the HV DC rail Vin. This high voltage current source is internally connected to the VCC pin and thus issued to charge the VCC capacitor. The V CC capacitor charge period corresponds to the Start–up phase. When the V CC voltage reaches 13V, the high voltage 9mA current source is disabled and the device starts working. The device enters into the switching phase.
To help increase the application safety against high voltage spike on pin8 a small wattage 1k _ series resistor is inserted between the Vin rail and pin 8. After this start-up the IC can distinguish between the different modes of operation using the following technique:

Mode Transition The LW latch is the memory of the working status at the end of every switching sequence. Two different cases must be considered for the logic at the termination of the SWITCHING PHASE: 1. No Over Current was observed 2. An Over Current was observed These two cases correspond to the two signals “NOC” in case of “No Over Current” and “OC” in case of Over Current. The effective working status at the end of the ON time memorised in LW corresponds to Q=1 for no over current, and Q=0 for over current. To enter the standby mode secondary side is reconfigured using D889 loop, this starts with the microprocessor ‘s pin 47 becomes high; as the standby port becomes high Q503 conducts and Q802 becomes off then D889 conducts and the high voltage output value becomes lower than the NORMAL mode regulated value. The shunt regulator IC118 is fully OFF. In the SMPS stand–by mode all the SMPS outputs are lowered except for the low voltage output that supply the wake–up circuit located at the isolated side of the power supply. In that mode the secondary regulation is performed by the Zener diode (D801) connected in parallel to the TL431. The secondary reconfiguration status can be detected on the SMPS primary side by measuring the voltage level at pin4 of TR802. In the SMPS stand–by mode the 3 distinct phases are: The SWITCHING PHASE: Similar to the Overload mode. The current sense clamping level is reduced. When VCC crosses the current sense section, the C.S. clamping level depends on the power to be delivered to the load during the SMPS stand–by mode. Every switching sequence ON/OFF is terminated by an OC as long as the secondary Zener diode voltage has not been reached. When the Zener voltage is reached the ON cycle is terminated by a true PWM action. The proper SWITCHING PHASE termination must correspond to a NOC condition. The LW latch stores this NOC status. The LATCHED OFF PHASE: The MODE latch is set. The START–UP PHASE is similar to the Overload Mode. The MODE latch remains in its set status (Q=1). The SWITCHING PHASE: The Stand-by signal is validated and the 200uA is sourced out of the Current Sense pin 2.

SMPS Switch Off
When the mains is switched OFF, so long as the electrolytic bulk capacitor provides energy to the SMPS the controller remains in the switching phase. Then the peak current reaches its maximum peak value, the switching frequency decreases and all the secondary voltages are reduced. The V CC voltage is also reduced. When VCC is less than 6,5V, the SMPS stops working

Line circuit
Line and frame drive are generated by IC403. The sync pulses are separated from the incoming video signal at pin 18/ 20/22 and used to control the internal circuitry of the IC. Line drive is produced by counting down the external 4.43 MHz crystal at pin 40 to 15.625 KHz locked to the incoming sync. This drive is output on pin 48 and feeds directly to the line drive transistor Q601. Note. That the output of IC403 Pin 48 is an open-collector and requires a pull up resistor, if the pin is open circuited for test no waveform will be seen. Q601 collector feeds the line output transistor Q603.
The line output stage is conventional with a transformer containing a split diode winding for EHT generation. Fifth harmonic tuning is achieved by capacitor C618/619.
A fly-back pulse is taken from pin 1 of the FBT transformer. This is required by IC403 (Pin 49) for burst / sync gating, and RGB line blanking. The ver_sync signal is output from the pin47 and fed to Pin41 of IC501. The H_sync pulse is taken from pin 1 of the FBT and fed to the micro at pin 40. These two signals are required by the micro for graphics timing and also for text.

B.C.L Circuit (Beam Current Limiter)
Beam current limiting is employed to protect the circuitry in the receiver, the CRT and to prevent excessive X Ray radiation in fault conditions. The current drawn by the CRT is monitored by the current drawn through the winding of the fly-back transformer that produces the EHT for the CRT anode. The end of the winding (Pin 10) is returned to IC403
Pins 46, the beam current drawn by the CRT passes through Q603 and develops a voltage on the collector proportional to the current (V=IxR).
The voltage on the collector will vary depending on the beam current being drawn reducing the brightness and contrast of the picture. If the voltage is sufficiently negative (indicating very high excess beam current) the output will be reduced, reducing the picture brightness and contrast.

Serial access CMOS 8K EEPROM 24C08
The 24C08 is a 8 Kbit electrically erasable programmable memory (EEPROM), organized as 4 blocks of 256*08 bits.
The memory is compatible with the I²C standard, two wire serial interface which uses a bi-directional data bus and serial clock.

EEPROM Initialization
If the E²PROM IC500 is replaced it will come fully programmed and therefore it is not necessary to initialize the new device. In some circumstances the E²PROM may become corrupted in use i.e. static discharge or lightning strike. If this happens, it is advised that the E²PROM is replaced.

MSP34X0G
The MSP 34x0G family of single-chip Multistandard Sound Processors covers the sound processing of all analog TVStandards worldwide, as well as the NICAM digital sound standards. The full TV sound processing, starting with analog sound IF signal-in, down to processed analog AF-out, is performed on a single chip. Figure 3 shows a simplified functional block diagram of the MSP 34x0G. This new generation of TV sound processing ICs now includes versions for processing the multichannel television sound (MTS) signal conforming to the standard recommended by the Broadcast
Television Systems Committee (BTSC). The DBX noise reduction, or alternatively, Micronas Noise Reduction (MNR) is performed alignment free.
Other processed standards are the Japanese FM-FM multiplex standard (EIA-J) and the FM Stereo Radio standard.
Current ICs have to perform adjustment procedures in order to achieve good stereo separation for BTSC and EIA-J.
The MSP 34x0G has optimum stereo performance without any adjustments. All MSP 34xxG versions are pin compatible to the MSP 34xxD. Only minor modifications are necessary to adapt a MSP 34xxD controlling software to the MSP 34xxG. The MSP 34x0G further simplifies controlling software.
Standard selection requires a single I2C transmission only. The MSP 34x0G has built-in automatic functions: The IC is able to detect the actual sound standard automatically (Automatic Standard Detection).

Furthermore, pilot levels and identification signals can be evaluated internally with subsequent switching between mono/ stereo/bilingual; no I2C interaction is necessary (Automatic Sound Selection). The MSP 34x0G can handle very high FM deviations even in conjunction with NICAM processing. This is especially important for the introduction of NICAM in China. The ICs are produced in submicron CMOS technology.

Service Menu (Service mode)
All system, geometry and white balance alignments are performed in Service Mode. Before starting the service mode alignments, make sure that all manual adjustments are done correctly.
To enter the service mode:
1. Press the MENU button on the remote control gun.

2. Press digit keys 4, 7, 2 and 5 consecutively.

1. Use the CURSOR UP  / DOWN  buttons to move between the registers.

2. Use the CURSOR LEFT / RIGHT buttons to change the data. See figure 5.
To memorize the adjustment:
It is not required to memorize the adjustment. Data are stored automatically.
To exit the Service Mode:
Switch the TV off using the mains switch.

Service Adjustments default values.

Using Colored Buttons
By using the four coloured buttons on the remote control different features or adjust may be accessed.

AVL
Press the RED button to activate or deactivate the AVL (Automatic Volume Level, between different broadcast channels).

GEOMETRY MENU
Press the GREEN button in order to change from the Main Service Menu to the Geometry Menu,

To return to the Main Service Menu it should be pressed the Menu button.

In the bottom area of this Menu, it can be seen “AUTO”. By pressing the WIDE MODE button it changes to 4:3 or 16:9 format. To perform the Geometry adjustments select the most suitable option:
- AUTO, entering 4:3 or 16:9 signal and proceeding with adjustments as below.
- 4:3, entering 4:3 signal and proceeding with adjustments as below.
- 16:9, entering 16:9 signal and proceeding with adjustments.