Introduction
The AT&T Beam 340U is a versatile 4G LTE USB mobile broadband modem designed for high-speed internet access. It offers fast LTE speeds, features a useful display, and includes a microSD card slot for expanded storage. This manual provides essential information for setting up, operating, and maintaining your device.
Package Contents
Upon opening the package, you should find the following items:
- NETGEAR Beam 340U Modem
- Device back cover
- 2-foot USB extender cable
- User manual (this document)

Image: The NETGEAR Beam 340U modem, a compact black USB device with a small display showing signal strength and data usage. It features a swivel USB connector for flexible positioning.
Setup
SIM Card Installation
The NETGEAR Beam 340U requires an active AT&T Standard size SIM card for operation. The SIM card is not included with the device. You will need to contact AT&T to acquire your complimentary SIM card, which is typically provided free with the activation of an account.
System Requirements and Installation
The modem is designed for plug-and-play functionality. It supports the following operating systems:
- Windows 8, 7, Vista, or XP (32 and 64-bit)
- Mac OS 10.8 and newer (Note: Official Mac support may be limited)
- Ubuntu Linux 9.04
Upon plugging the device into a USB port, it may initially present itself as a storage device. For proper functionality, it must be switched to a serial device. While newer Linux kernels may handle this automatically, the 340U may not be pre-configured in some usb-modeswitch-data databases, potentially requiring manual configuration for Linux users.
Operating Instructions
Connectivity and Speed
The modem supports download speeds up to 100Mbps and upload speeds up to 50Mbps, leveraging AT&T's 4G LTE network. Ensure you are within an AT&T LTE coverage area for optimal performance.
Network Frequencies
The modem supports the following frequency bands:
- GPRS/EDGE: 850/900/1800/1900MHz
- UMTS: 850/1900/2100MHz
- LTE: Bands 2, 4, 5, and 17
It also features 2x2 MIMO antenna ports for enhanced signal reception.
MicroSD Card Slot
The device includes a microSD card slot, supporting cards up to 32 GB, allowing for portable storage.
Integrated Display
A small display on the modem provides useful information, such as signal strength and data usage. For Windows 8 users, it also integrates with live tiles.
Maintenance
To ensure the longevity and optimal performance of your NETGEAR Beam 340U modem, follow these maintenance guidelines:
- Cleaning: Use a soft, dry cloth to clean the exterior of the device. Avoid using liquid cleaners or aerosols.
- Storage: Store the modem in a cool, dry place when not in use. Avoid exposing it to extreme temperatures, direct sunlight, or high humidity.
- Handling: Handle the device with care. Avoid dropping it or subjecting it to strong impacts.
- USB Port: Ensure the USB port on your computer is clean and free of debris before inserting the modem.
Troubleshooting
General Connectivity Issues
- No Connection: Ensure your AT&T SIM card is active and properly inserted. Verify that you are in an area with AT&T 4G LTE coverage.
- Slow Speeds: Signal strength can affect speed. Try repositioning the modem or using the included USB extender to find a better signal.
Operating System Specific Issues
- Mac OS: While Mac OS 10.8 and newer are listed as supported, official Mac support may be limited. Users might experience compatibility challenges.
- Linux: NETGEAR (and Sierra Wireless, the underlying technology) does not officially support Linux for this device. The modem may initially appear as a storage device and needs to be switched to a serial device. This process might require manual configuration or an updated usb-modeswitch-data database, as the 340U may not be included by default in some distributions.
Network Compatibility
This device is unlocked and compatible with GSM carriers that use SIM cards for service, such as AT&T and T-Mobile, as well as GSM SIM cards from providers like H20 and Straight Talk. It will not work with CDMA carriers that do not use SIM cards for service, such as Sprint, Verizon, Boost, or Virgin. Always contact your network provider prior to purchasing for verification of compatibility.
Power Source
The NETGEAR Beam 340U is a plug-and-play device and does not require a separate battery. It draws power directly from the USB port of your computer or compatible USB hub.
Specifications
| Brand | AT&T (Manufactured by NETGEAR) |
| Model Number | 340U |
| Connectivity Technology | USB |
| Supported Networks | 4G LTE, UMTS, GPRS/EDGE |
| Frequency Bands | GPRS/EDGE: 850/900/1800/1900MHz; UMTS: 850/1900/2100MHz; LTE: Bands 2, 4, 5, 17 |
| Max Download Speed | Up to 100Mbps |
| Max Upload Speed | Up to 50Mbps |
| MicroSD Card Support | Up to 32 GB |
| Operating System Support | Windows 8, 7, Vista, XP (32/64bit); Mac OS 10.8+; Ubuntu Linux 9.04 |
| Item Weight | 1.91 ounces |
| Product Dimensions (LxWxH) | 1.97 x 0.46 x 2.58 inches |
| Color | Black |
Warranty and Support
For warranty information and technical support, please contact AT&T customer service or visit the official NETGEAR support website. Specific warranty terms and conditions may vary and are typically provided at the time of purchase or available through the manufacturer's official channels.
For AT&T support, you can visit their official website or contact their customer service line. For NETGEAR product support, refer to the support section on netgear.com/support.