Black Box AC1000A User Manual page 20

Problem:
Solution:
Problem:
Solution:
Problem:
Solution:
Serial communication doesn't work correctly.
• Are the serial devices connected properly? Are the serial
parameters correct for source/destination devices?
• Are the serial cables terminated correctly? If a null-modem
cable is used, it must be placed at the receiver end.
• When using RS-232 transmitters or receivers, the serial signal is
a unidirectionally broadcast mode only. In this mode, all other
CAT5 Multi VGA System devices must be the simplex serial
type. For assistance, contact Technical Support.
• The last device in a quad hub or daisychain configuration must
be a standard receiver unit with a terminated serial board
(default).
"Blue shift" of video signal (a slight blue haze appears in areas of
the screen that normally would appear black, or a slight blue tint
appears in areas that would normally appear white). This is most
often seen in applications that use inexpensive monitors, but it
sometimes occurs with more expensive equipment.
1. Go into the monitor's menu and select the "Blue-Black Level"
function.
2. Use the appropriate command to reduce the level.
3. Reduce the "Blue-Black Level" until the black areas in the
image truly appear black. For monitors with a "Blue Drive"
adjustment, reduce this setting until the white areas of the
screen appear normal.
"Green shift" or "green washout" on multimedia signals.
Please contact Technical Support.
The standard video/serial model (AC1004A–AC1007A) is
designed to function with DC coupled signals in which the black
level is referenced to 0 volts. Nearly all VGA cards function this
way.
Some media servers, however, provide AC coupled signals and
can cause a green color shift in the video. This is a result of the
CHAPTER 4: Troubleshooting
19