Acer H236HL Acer H236HL Monitor Service Guide - Page 11

9 1.3.2 Input Signals: Video Input Signals Range (Analog RGB Signal) No. Symbol Item M in Max Uni 1 Fh Horizontal Frequency 30 83 kH 2 Fv Vertical Frequency 56 75 H 3 Fclk Pixel Clock Frequency 148.5 M 4 Vih High Level Input 2.4 V 5 Vil Low Level Input 0 0.8 V 6 Video RGB Analog Video Level 0 0.7 V 1.3.2.1 Video Signal Amplitudes: The video inputs consist of Red, Green and Blue signals each has its own coaxial cable terminated at the monitor. These video signals are analog levels, where 0V corresponds to black, and 700mV is the maximum signal amplitude for the respective color. The video signal is terminated with 75 ohms. 1.3.2.2 Video Signal Termination Impedance: The analog video signal termination shall be 75 ohm. 1.3.2.3 Synchronization (Sync) Signals: The Horizontal Sync (HS) TTL signal is used to initiate the display of a horizontal line. HS may be either active high or active low according to the timing. The Vertical Sync (VS) TTL signal is used to initiate the display of a new frame. VS may be either active high or active low according to the timing. 1.3.2.4 Sync Signal Levels: Level: L = 0V ~ 0.8V H = 2.4V ~ 5V 1.3.2.5 Abnormal Signal Immunity: The monitor shall not be damaged by improper sync timing, pulse duration, absence of sync, abnormal input signal amplitude, or any other anomalous behavior of a graphics card. 1.3.2.6 Digital TMDS Input (DVI signal input): 1.3.3 User Controls and Indicators: Signals used for mode detection: -Nominal horizontal frequency -Nominal vertical frequency -Horizontal sync. Pulse polarity -Vertical sync. Pulse polarity The tolerance for detecting the horizontal frequency is between ±1KHz from center frequency The tolerance for detecting the vertical frequency is between ±0.5Hz from center frequency 1.3.3.1 Power On/Off Switch: The monitor shall have a power control switch visible and accessible on the front of monitor.