Monday, November 30, 2009

REPAIR TIPS: Dell E151FPp 15" LCD Monitor

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SYMPTOM: No picture visible.


PROBLEM: Bad Inverter board. Backlights not coming on.


SOLUTION: I had 5 of these guys all with the same exact problem. Replaced the small fuse and the electrolytic cap on the inverter board. Now they all all work like a charm!

Tuesday, November 17, 2009

COMMON FAILURE IN 17" DELL, BENQ AND OTHERS

COMMON FAILURE IN 17" DELL, BENQ AND OTHERS



2SC5707-

Applications

• DC-DC converter, relay drivers, lamp drivers,

motor drivers, strobes.

Features

• Adoption of FBET, MBIT process.

• Large current capacitance.

• Low collector-to-emitter saturation voltage.

• High-speed switching.

• High allowable power dissipation.

SANYO Electric Co.,Ltd. Semiconductor Company

TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110-8534 JAPAN

Ordering number : ENN6913

2SA2040 / 2SC5707

High Current Switching Applications

Package Dimensions

unit : mm

2045B


[2SA2040 / 2SC5707]
http://www.datasheetcatalog.org/datasheet/sanyo/2SC5707.pdf




IRFU9024N - Power MOSFET(Vdss=-55V, Rds(on)=0.175ohm, Id=-11A) - International Rectifier








Friday, November 06, 2009

Westinghouse LCM-22w3 repair


SYMPTOM: One had no power. Another one had power, but no picture.


PROBLEM: 7 bad power supply capacitors.
3 x 220uF/25v
3 x 1000uF/25v
1 x 2200uF/10v

SOLUTION: Replaced caps.

Wednesday, November 04, 2009

HP Pavillion F1903 19" LCD Monitor Repair



SYMPTOM: Powers on but display shuts off after a few seconds.

PROBLEM: It's actually the CCFL backlight power inverter shutting off due to a fault detected.

SOLUTION: Replaced 2 electrolytic capacitors, 2 poly caps (big blue bastards), and all four 2SC5706 transistors (3-legged little bastards). Used 2SC5707 as replacement.

LCD Monitors: Glossy vs. Matte Finish

Q: I've noticed that some flat-panel LCDs have glossy screens, while others have matte screens. Is there any advantage to one versus the other?

A: Each screen has its advantages and disadvantages, which is why manufacturers waver between the two. Glossy screens produce an image that's generally regarded as "richer." Admittedly, that's a nebulous term, but essentially it means there is more color depth and vibrancy. On the downside, glossy screens are more susceptible to glare, reflecting light from windows and light bulbs. And they tend to show fingerprints and smudges more readily, especially when they are off.

Matte screens tend to handle glare better, due to a polarized coating over the glass that diffuses ambient light. A side effect of the matte finish is a slight blurring, reduced contrast and a narrower viewing angle.

Which is better is a matter of environment and personal preference. If the screen is in a room that's generally dark, consider a glossy finish. In a controlled environment it offers a best-case picture. But I wouldn't be too afraid of a matte finish. Most of us use our screens in mixed light where the minor qualitative difference is offset by the anti-reflective benefit.