- ページ 16

DVR HIKVISION DS7208HVI-ST/SEのPDF 製品／メンテナンス・マニュアルをオンラインで閲覧またはダウンロードできます。HIKVISION DS7208HVI-ST/SE 20 ページ。

6. DS80054 Mainboard Failure Analysis

VGA and VOUT and output image, but not at the same time output system

menu, the system default first detection VGA output, then detection VOUT

output

Boot to meet VGA monitor (or also meet VGA display and VOUT monitor),

BAV99 (Q9) PIN 3 low level effective, display output VGA signal and system

menu, monitor only VOUT signal

Boot first meet VOUT monitors, BAV99 (Q9) 3 feet is high level, the high level

signal feedback to the CPU, monitor output VOUT signal and system menu,

display show only the VGA signal

Note: ① BAV99 (Q9) 3 feet high level, only output signal VGA monitor, monitor

and output signal and system VOUT menu

② BAV99 (Q9) 3 feet low level, display and VGA output signal and system

menu, monitor only output VOUT signal

6.3 Fault Analysis

①. No VGA Output

Step 1: measure 1 K resistance (RL50/51), or replacement (1 K value too large,

LVC07A chip PIN 2 VS signal output, PIN4 HS signal output voltage

value will be lower, then cause no VGA output)

Step 2: measurement 33Ωresistance (RG30/31), or replacement

Step 3: using a multimeter to measure LVC07A PIN 1 input (VS signal) voltage

about 3.3V and PIN 3 input (HS signal) voltage 3V also, and then

measure PIN 2 output (VS signal) voltage about 5V, the PIN4 output

(HS signal) voltage about 4.3V, otherwise LVC07A ruled out

Step 4: measurement capacitance CG1, CG2 impedance , or replacemet