
ASKING FOR ASSISTANCE
Technical Support:
Telephone (818)772-9100
(800) 545-6900
Fax (818)772-9120
Technical Support Hours:
8:00 AM to 5:00 PM Monday through Friday PST
Write To:
Gefen Inc.
c/o Customer Service
20600 Nordhoff Street
Chatsworth, CA 91311 U.S.A.
www.gefen.com
support@gefen.com
Gefen Inc. reserves the right to make changes in the hard ware, packaging and any
accompanying doc u men ta tion without prior written notice.
The HD-SDI to DVI Loop is a trademark of Gefen Inc.
© 2005 Gefen Inc., All Rights Reserved
Notice

TABLE OF CONTENTS
1
Introduction
2
Operation Notes
3
Panel Descriptions
4
Supported Input/Output Resolutions/OSD and Infrared Remote Functions
5
OSD and Infrared Remote Functions
6
OSD and Infrared Remote Functions
7
Wiring of the RS422-RS232 Cable
8
Recommended LCD Monitors
9
Firmware Update Procedure
10
Specifi cations
11
Warranty

INTRODUCTION
The HD-SDI to DVI Loop is a compact digital video interface that converts HD-SDI, SDI,
DVI-D, and DVI-A (Analog RGB) to DVI-D (digital RGB). It automatically detects the input scan rate and supports a wide variety of video formats including PAL, NTSC, 720p,
1080i, 1080p.
The HD-SDI to DVI Loop can be connected to computer LCD monitors, HDTV Televisions with 720p, or 1080p, video projectors and displays (Plasma, DLP, D-ILA, etc.).
CONTENTS
The HD-SDI to DVI Loop consists of:
--- (1) HD-SDI to DVI Loop
--- (1) 5VDC Power Supply
--- (1) User's Manual
1

OPERATION NOTES
On power up, the HD-SDI to DVI Loop will automatically detect the input format of the
selected input and will send a message to the monitor connected via DVI requesting its
EDID. The EDID parameters of the connected monitor will be used by the HD-SDI to
DVI Loop to determine its output resolution.
The Loop's DVI-D output has 2 major controls: Resolution and Frequency.
Resoluton: Can be set to Auto (default) or forced to 1280x720, 1280x1024, 1920x1080
or 1920x1200
Frequency: Can be set to 60Hz (default) or forced to Frame Sync.
Resolution
1. The output resolution will be set to match the monitor up to 1920x1200.
•If the EDID response of the monitor is not recognized or higher than 1920x1200, the
Loop will default to 1280x1024. If the monitor doesn't support 1280x1024, the output
resolution can be forced using the infrared remote control and without the On Screen
Display (OSD) interface by using the TV/Video + Number combination according to the
following table:
o TV/Video + 0 => Auto Mode
o TV/Video + 1 => 800x600
o TV/Video + 2 => 1024x768
o TV/Video + 3 => 1280x720
o TV/Video + 4 => 1280x768
o TV/Video + 5 => 1280x1024
o TV/Video + 6 => 1400x1050
o TV/Video + 7 => 1600x1200
o TV/Video + 8 => 1920x1080
o TV/Video + 9 => 1920x1200
•If the EDID reports 1920x1080 interlaced, the unit will default to output 480p. The
480p output should only be used to access the OSD and force the output mode to 720p
if the TV supports it.
Frequency
The default frequency is 60Hz because it works with all displays. If your display supports
lower frequencies and if your input source is running at 24/48, 25/50 Frames/Fields per
second, you can avoid motion artifacts by forcing the output frequency to Frame Sync.
2