Sunday, October 7, 2018

HP s7650 CRT monitor – How to enter the service mode, schematic, adjustments


   Exercise care when servicing this chassis with power applied. Many B plus and high voltage terminals are exposed which, if carelessly contacted, can cause serious shock or result in damage to the chassis. Maintain interconnecting ground lead connections between chassis and picture tube dag when operating chassis.
   Certain HV failures can increase X-ray radiation. Monitor should not be operated with HV  levels exceeding the specified rating for the chassis type. The maximum operating HV specified for the chassis used in this monitor is  23.0KV ± 1KV  with a line voltage of 120/240 VAC. Higher voltage may also increase possibility of failure in HV supply.
It is important to maintain specified values of all components in the horizontal and high voltage circuits and anywhere else in the monitor that could cause a rise in high voltage or operating supply voltages. No changes should be made to the original design of the monitor.
   To determine the presence of high voltage, use accurate, high impedance, HV meter connected between second anode lead and CRT dag grounding device. When servicing the High Voltage System, remove static charge from it by connecting a 10K ohm resistor in series with an insulated wire (such as a test probe) between picture tube dag and 2nd anode lead.(AC line cord disconnected from AC power outlet.)
Factory preset Timings Adjustment:
A. Press MENU Key to show OSD window press Up or Down Key to switch the functional controls.
B. Press the Up Key to select the "MORIE" function, then press the SELEC Key. While do not release the SELEC Key until the OSD window changed to the Factory preset window.
C. The Factory preset window contains the following functional controls. Select one of the control. Then press the Up/Down Key to adjust its value for the optimum picture.
D. To switches the input signal to the other Timing Mode. Please follow step A ~ C to get the optimum picture.(H/V-size:312*234mm)
E. Select the "BACK " RETURN function and press the MENU Key, then the Factor Preset window will be returned to the original OSD window.(user's operating condition)
F. The setting data of the CONTRAST, BRIGHTNESS, ROTATION, and COLOR TEMPERATURE are common mode saved in the memory. Don't needed adjust it individual at every timing Mode and save in the memory.
Micro Controller Circuit
The IC101 contains a 6502/8051 8-bit CPU core, 512 bytes of RAM, 16K bytes of ROM,14 channel 8 bit PWM D/A converters, 2 channel A/D converters for key detection, one 8 bit pre-loadable base timer, internal H-sync and V-sync signals processor providing mode detection, watch- dog timer preventing system from abnormal operation, and an I²C bus interface.
Circuit diagram: PWB
15-Pin Display cable
H/V sync signals processor
The functions of the sync processor include polarity detection, H-SYNC & V-SYNC signals counting, Programmable SYNC signals output, free running signal generator. Pin39/Pin40 are for the H-SYNC and VSYNC input, Pin32/Pin33 will output the same signal as input sync signal without delay, and the polarity are setting in the positive. When no signal input, the Pin32 will output a 72Hz V-SYNC free run signal. The Pin33 will output a 48KHz H-SYNC free run signal. for the monitor testing use.
Deflection Circuit
The deflection circuit is achieved by a high performance and efficient solution IC 401 (STV9118) for this monitor. The concept is fully DC controllable and can be used in applications with a micro-controller solutions. The STV9118 provides sync. Processing with full auto sync. Capability, a flexible SMPS block and an extensive set of geometry control facilities. Further the IC generates the drive waveforms for DC coupled vertical boosters to the STV9302A.
Horizontal Oscillator
The oscillator is of the relaxation type and requires a capacitor of C409 at pin6. The free running frequency is determined by a resistor R412 from pin8 to ground.
PLL 1 Phase Detector
The phase detector is a standard one using switched current sources. It compares the middle of H-sync. With a fixed point on the oscillator saw-tooth voltage. The PLL loop filter C435, C437, R411 is connected to Pin9.
PLL2 Phase Detector
This phase detector is similar to the PLL1 detector and compares the line flyback pulse at pin 12 with the oscillator saw-tooth voltage. The PLL2 detector thus compensates for the delay in the external H-deflection circuit by adjusting the phase of the HDRV output pulses. The phase between H-flyback and H-sync can be controlled at pin5.
X-ray Protection
The X-ray protection input pin25 provides a voltage detector with a precise threshold. If the voltage exceeds this threshold for a certain time, an internal latch switches the whole IC into protection mode. In this mode several pins are forced into defined states:
Pin28 (BDRV) is floating
Pin26 (HDRV) is floating
Vertical Oscillator
The vertical free –running frequency is determined by the capacitance C613 at pin22. Usually the free-running frequency should be lower than the minimum trigger frequency.

Thursday, September 13, 2018

Jamo MPA201, Jamo SW600E, Jamo A300 – Schematics [circuit diagrams]


Jamo MPA201(120V) circuit diagram
Used ICs: NE5532P, TL072CN, NJM4560L, [TIP35C, TIP36C Output transistor pair]
Jamo SW600E sub-woofer system amplifier circuit diagram

Used ICs: TL084, [BDV64B, BDV65B output transistor pair]
Jamo A300 stereo amplifier circuit diagram
Used ICs: TL084, [IRF640 x 6- FET output transistors]

Tuesday, August 28, 2018

Onida Oxygen 29 – 29 inch CRT TV circuit diagram (Schematic)

Used ICs: TDA9376, TDA8357/N1, MC24C16-BN6, TAEC-G021D(Tuner), TDA7297, NJM1136L, HFE4052BP, STR-F6655TDA6107

Saturday, July 7, 2018

Vizio, LG and TCL LCD TV SMPS schematics

KLS 420SC-E SMPS (LG AND VIZIO 42 inch LCD TV power supply schematic
Used ICs: BD9897FS, LM209, FDD8447L(FET)
TCL 40E081-PWF SMPS
Used ICs: 13A650(FET), OB2273A

Saturday, June 9, 2018

Hitachi LE29H306 – LCD TV SMPS schematic

Used ICs:  MIP2M40MSSCF, FA5640N-C6-TE3, BD8779EFV-E2
SMPS Circuit diagram
Back-light inverter 
PWB

RCA L32HD32D – power board schematic

Used ICs: MIP2F4(Switching regulator), PS2561AL 1-1-V(W) Optocoupler, SSC9501(Power control)

Tuesday, May 29, 2018

Aiwa XG990, NSX990, NSX992 compact disc stereo system – schematic


Aiwa compact CD  stereo system circuit diagram – HE,U,C,E,K and Z models
Click on the schematics to magnify

Saturday, May 26, 2018

A 715G6297 PSU Philips LCD TV SMPS – Power Board schematic


Used ICs: PF6200, TK6A65D(FET), EL817M(X)-Opto-coupler, PF7001S, AO4286

All power supplies are a black box for Service. When defective, a new board must be ordered and the defective one must be returned, unless the main fuse of the board is broken. Always replace a defective fuse with one with the correct specifications! This part is available in the regular market.
Consult the Philips Service web portal for the order codes of the boards.
Important delta’s with the 3010/4010/5010//5110 platform are:
• New power architecture for LED backlight
• “Boost”-signal is now a PWM-signal + continuous variable.
The control signals are:
• Lamp “on/off”
• DIM (PWM)
In this manual, no detailed information is available because of design protection issues.
The output voltages to the chassis are:
• +12V for main board and audio amplifier (standby and on-mode) (for 715G6197,715G6297,715G6550)
• +12V(on-mode) ,+8.5V(Standby-mode)for main board and audio amplifier (for 715G6934 715G6677 715G6973)
• Output to the display; in case of
- IPB: High voltage to the LCD panel
- PSL and PSLS (LED-driver outputs)
- PSDL (high frequent) AC-current.
The diversity in power supply units is mainly determined by the diversity in displays.
The following displays can be distinguished:
• CCFL/EEFL backlight: power board is conventional IPB
• LED backlight:
- side-view LED without scanning: PSL power board
- side-view LED with scanning: PSLS power board
- direct-view LED without 2D-dimming: PSL power board
- direct-view LED with 2D-dimming: PSDL power board.
PSL stands for Power Supply with integrated LED-drivers.
PSLS stands for a Power Supply with integrated LED-drivers with added Scanning functionality (added microcontroller).
PSDL stands for a Power Supply for Direct-view LED backlight with 2D-dimming

A 715G6297 PSU Philips LCD TV SMPS – Power Board schematic
A 715G6297 PSU Philips LCD TV SMPS – LED driver schematic
A 715G6297 PSU Philips LCD TV SMPS PWB