
Contents
1 Introduction 1
2 Getting Started 2
2.1 Achieving the Best Performance 2
2.2 Recycling Kramer Products 3
3 Overview 4
4 Defining the VS-401USB 4x1 USB Switcher 5
5 Connecting the VS-401USB 6
5.1 Connecting a PC 7
6 Operating the VS-401USB 8
6.1 The Application Software 8
7 Firmware Upgrade 9
8 Technical Specifications 10
9 Default Communication Parameters 11
10 Kramer Protocol 2000 12
11 Protocol 3000 14
11.1 Kramer Protocol 3000 Syntax 14
11.2 Kramer Protocol 3000 Commands 17
Figures
UFigure 1: VS-401USB 4x1 USB SwitcherU 5
UFigure 2: Connecting to the VS-401USBU 7
VS-401USB – Contents i

1 Introduction
Welcome to Kramer Electronics! Since 1981, Kramer Electronics has been
providing a world of unique, creative, and affordable solutions to the vast range of
problems that confront the video, audio, presentation, and broadcasting
professional on a daily basis. In recent years, we have redesigned and upgraded
most of our line, making the best even better!
Our 1,000-plus different models now appear in 11 groups that are clearly defined
by function: GROUP 1: Distribution Amplifiers; GROUP 2: Switchers and Routers;
GROUP 3: Control Systems; GROUP 4: Format/Standards Converters; GROUP
5: Range Extenders and Repeaters; GROUP 6: Specialty AV Products; GROUP
7: Scan Converters and Scalers; GROUP 8: Cables and Connectors; GROUP 9:
Room Connectivity; GROUP 10: Accessories and Rack Adapters and GROUP 11:
Sierra Video Products.
Congratulations on purchasing your Kramer VS-401USB 4x1 USB Switcher,
which is ideal for the following typical applications:
• Projection systems in conference rooms, boardrooms, auditoriums, hotels
and churches, production studios, rental and staging
• Any application where high quality conversion and switching of multiple and
different video signals to graphical data signals is required for projection
purposes
VS-401USB - Introduction 1

2 Getting Started
We recommend that you:
• Unpack the equipment carefully and save the original box and packaging
materials for possible future shipment
• Review the contents of this user manual
• Use only the power cord that is supplied with this machine
Go to http://www.kramerelectronics.com to check for up-to-date user
manuals, application programs, and to check if firmware upgrades
are available (where appropriate).
2.1 Achieving the Best Performance
To achieve the best performance:
• Use only good quality connection cables to avoid interference, deterioration
in signal quality due to poor matching, and elevated noise levels (often
associated with low quality cables)
• Do not secure the cables in tight bundles or roll the slack into tight coils
• Avoid interference from neighboring electrical appliances that may adversely
influence signal quality
• Position your Kramer VS-401USB away from moisture, excessive sunlight
and dust
This equipment is to be used only inside a building. It may only be
connected to other equipment that is installed inside a building.
Caution: There are no operator serviceable parts inside the unit
Warning:
Warning:
2 VS-401USB - Getting Started
Use only the Kramer Electronics input power wall
adapter that is provided with the unit
Disconnect the power and unplug the unit from the
wall before installing