StarTech.com USB56KEMH2 56K USB dial-up and fax modem: specs and uses

The StarTech.com USB56KEMH2 is a small external modem that connects to a computer by USB and to the phone network through a standard RJ11 telephone jack. It adds dial-up internet and fax capability to laptops and desktops that no longer have a built-in modem. Here is what its specs mean and where a device like this is still used.

What it does

StarTech.com describes it as a hardware-based USB 2.0 data and fax modem. It lets a computer reach the internet through a dial-up service when broadband isn't available, and it lets the computer send and receive faxes. The brand lists uses such as rural internet access, security systems, point-of-sale credit authorization and faxing.

Hardware-based, not software-based

Some older "soft" modems left much of the signal processing to the computer's CPU. This one is described as a controller-based modem that does that work on-chip, with a Conexant CX93010-21Z controller. In practice that means the computer's processor isn't tied up during a connection, and the modem behaves more predictably with software that expects a conventional hardware modem.

Speeds and standards explained

The listing gives 56 Kbps down and 33.6 Kbps up for data, and 14.4 Kbps for fax. Those are the typical limits of analogue dial-up: the 56K figure is a best case and depends on line quality and the provider. It is not a promise.

• Data standards: V.92, V.90, V.34, V.32bis, V.32, V.22bis, V.22, V.23, V.21, Bell 212A and Bell 103. V.92 and V.90 are the 56K standards; the others let the modem fall back to slower speeds with older equipment.
• V.44 compression: a data-compression standard that can speed up the transfer of compressible content over a dial-up link.
• Fax standards: V.17, V.29, V.27 and V.21 Ch 2, plus EIA/TIA 578 Class 1 and T.31 Fax Class 1.0, which are the command sets fax software commonly relies on.
• DTMF support: the tone dialling used by modern phone systems.

Voice and Caller ID

StarTech.com says the modem supports voice calls through the computer, plus Caller ID. These features depend on software that can use them, so check that your voice or fax application is compatible with this modem before relying on them.

Power and portability

It measures roughly 3.0 x 1.1 x 0.8 inches and weighs about 0.1 lb, so it slips into a laptop bag. It draws power from the USB connection, so no separate adapter is needed. The brand says it is TAA compliant.

Drivers and compatibility

Drivers are listed for Windows and Windows Server, for macOS 10.9 to 12.x and for Linux with kernel 3.16 and up. The Windows drivers are available as a download. Newer operating system releases may need a driver update or may not be covered, so check the manufacturer's support page for your exact version.

Who it suits

• People in places without broadband who still depend on a dial-up line.
• Offices that keep a fax workflow, or businesses with older terminals and alarm systems that report over analogue lines.
• Travellers who want a backup connection method.
• Anyone running legacy equipment or software that expects a modem.

What to check before you buy

• Phone line type: it needs an analogue line with an RJ11 jack. Many modern digital or VoIP phone lines don't work with dial-up modems without an adapter, so ask your provider.
• Provider support: confirm your dial-up provider is still operating and compatible.
• Operating system: compare your version of Windows, macOS or Linux with the driver list.
• Fax software: check that the application you plan to use supports the modem.
• Country: telephone standards differ between countries, so confirm the modem is approved for use where you live.

The short version

• An external 56K USB modem for dial-up and fax, powered through USB.
• V.92 and V.90 data support, V.44 compression, and fax up to 14.4 Kbps.
• One RJ11 jack, Caller ID and voice support through compatible software.
• Drivers listed for Windows, macOS 10.9 to 12.x and Linux kernel 3.16 and up.

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