Skip to main content

Changhong PF29GA18A – How to enter service mode – circuit diagram – 29 inch color TV


ETA-1D chassis is applied in PF29GA18A series.
By use of Toshiba V/C/D-MCU 2IN1 IC for TV small signal processing and bus control, the chassis enables TV tuning, adjustment, control and picture correction, featuring
high-integration, high-performance-to-price ratio and high-reliability and compact circuit with fewer external components. The chassis, widely used in small and medium TVs,
provides much more convenience for manufacturing and technical service. It includes:
2IN1 IC 8897PSBNG-4VB6 for PAL/NTSC small signal processing and bus control [TMPA8897CMANG /CPANG/CRANG /CSANG]
EEPROM AT24C16 for data memory
LA78041 for vertical output power amplifying
LA42102 for audio power amplifying
TA1343N for audio processor
FSCQ1265RTYDTU for power circuit adjustment and control.
BSC68DG (FBT)
Mask ROM: TMPA8897CPBNG (ROM size: 48k)
Mask ROM: TMPA8897CRBNG (ROM size: 56k)
Mask ROM: TMPA8897CSBNG (ROM size: 64k)
OTP ROM: TMPA8897PSBNG (ROM size: 64k)
Color systems: PAL, NTSC
Sound systems: D/K B/G I M
236 programs preset
AV stereo
I2C bus control
Electronic program table
Intelligent lock
Biorhythm
Calendar inquiry.
To enter the DESIGN/SERVICE mode
Set the volume to 0.
Press and hold the MUTE button on the remote control, and press the MENU button on the TV to enter the SERVICE mode.
In this case, blue “D” is displayed on the upper center of the screen.
To exit from the D mode, turn off the TV set by the POWER button on the remote control.
Caution: The user service mode adjustment can be changed only when service personnel adjust the whole set data during servicing. As the control data have dramatic effects on functions and performance of the TV, service personnel should not tell user how to enter the SERVICE mode to avoid improper data settings.
Circuit diagram
It’s impossible to check the power part separately from the main chassis board as the part is mounted on the main chassis board. The power components, etc. should be checked for burnout when power-on. If burned out, do not power on the TV again until the cause is found out.
SMPS and system-chroma junge circuit - Split
Click on the pictures to zoom in


Labels:

Comments

Post a Comment

Popular posts from this blog

NE566 Function Generator Circuit Diagram

The NE566 Function Generator is a Voltage-Controlled Oscillator of exceptional linearity with buf fered square wave and triangle wave outputs. The frequency of oscillation is determined by an external resistor and capacitor and the voltage applied to the control terminal. The Oscillator CAN be programmed over a ten-to-one frequency range by proper selection of an external resistance and modulated over a ten-to-one range by the control voltage, with exceptional linearity.  FMAX = 1 MHz     WIDE 1000:1 Continuous Sweep Possible  NE566 Function Generator Circuit Diagram Pdf Datasheet  Sourced by : Circuitsstream
Post a Comment
Read more

TDA2030 complete tone control

At this time I present a series of amplifiers that use IC TDA2030, but this series is equipped with a tone control. Tone controls include Bass, Treebel, and Volume. Power amplifier and tone control has been put together in a single PCB. As well as its power supply circuit was also used as one with the power amp, and tone control. Making it easier in the installation and will look neat. Schematics Layout PCB PCB design This amplifier is a mono amplifier type, can be modif for guitar amplifiers. If not coupled amplifier (mic preamp) then you must deactivated potensio treble and bass, why? because if not using a mic preamp and still maintain potensio treble and bass sound input (input) from the guitar will not or the maximum discharge is not tight on the speakers. So you must deactivated a way to decide which directly connected capacitor with the tone control circuit, and capacitor were connected directly to potensio volume and input jack.
Post a Comment
Read more

Simple Preamplifier and High to Low impedance Converter Circuit Diagram

This is the Simple Preamplifier and High to Low impedance Converter Circuit Diagram. This circuit matches the very high impedance of ceramic cartridges, unity gain, and low impedance output.  Simple Preamplifier and High to Low impedance Converter Circuit Diagram By `loading` the cartridge with a 2M2 input resistance, the cartridge characteristics are such as to quite closely compensate for the RIAA recording curve. The output from this preamp may be fed to a level pot for mixing. Sourced By: Circuitsproject
Post a Comment
Read more