Black Box ACS251A - Manual (Page 15)

14
SERVSWITCH™ BRAND FIBER KVM EXTENDER II AND II-SM
When the Local Unit detects that the CPU has switched to a different resolution,
refresh rate, etc., it will adjust all digitizing parameters automatically. Only a few
seconds later, you will again have a sharp, crisp, and colorful image without having
to move any switches or turn any dials. The Local Unit checks all video parameters
continuously, so video quality is maximized at all times.
After the Local Unit digitizes the video, it transmits the digital data across the
fiber as a serial stream. Inside the Remote Unit, the signal is converted back into
the original analog values, which it outputs from its “Video” connector. The
resolution of the output signal is always same as that of the original input, but its
vertical refresh rate is kept constant (by dropping or repeating frames). No matter
what their input refresh rate is:
• DOS-mode resolutions will be output at a refresh rate of 85 Hz.
• Non-DOS-mode resolutions up to 1152 x 864 will be output at a refresh rate of
75 Hz.
• 1280 x 1024 resolution will be output at a refresh rate of 60 Hz.
Make sure that the remote monitor can support your chosen resolution at the
corresponding rate. If it doesn’t, the display will look bad or be totally blank.
The Remote Unit will always output separate horizontal and vertical sync from its
“Video” connector on the standard VGA Hsync and Vsync pins (HD15 pins 13 and
14). If you need to connect a remote monitor that uses some other type of sync
and/or separate BNC connectors rather than an HD15 VGA connector, call Black
Box Technical Support for assistance.
3.2 Mouse Compatibility
The Extender supports all common PS/2 style mice and pointing devices including
two-button mice, three-button mice, wheel mice such as the Microsoft
®
Intellimouse ® , trackballs, etc.
3.3 Sound Processing
The Local Unit receives stereo sound input and converts it into a monaural “sum”
signal. (The Local Unit supports standard input-signal levels of 0.7 V
eff
[effective
volts], equivalent to about 2 Vpp [volts peak-to-peak].) This signal is then digitized
as 8-bit data by sampling at a rate of about 16 kHz. The Remote Unit converts the
signal back to analog audio and outputs the monaural sound simultaneously on
both the left and right stereo channels. You can adjust the volume using the
volume controls of your active speakers or other audio-output devices and/or your
CPU’s operating system.