STARTECH
STARTECH USB to Null Modem Serial Adapter Cable 30cm
Connects a null-modem serial device to a USB port with a 30 cm cable and two DB9 screws
- Connect legacy serial gear via USB
- 30 cm cable keeps workspaces tidy
- Null modem wiring links two DTE devices directly
- Two DB9 screws secure each connection
- Quick-start guide gets you running fast
What this adapter does
The StarTech cable converts a USB port into a DB9 serial connection using a null-modem pinout. It is built for technicians and engineers who need to configure routers, switches or industrial equipment that only accept a serial console.
Practical limits of the USB-serial link
The 30 cm length restricts placement to immediately beside the host computer. Throughput is bound by the USB-serial bridge chip, so high-speed bulk transfers are not realistic. The DB9 screws provide a secure fit but the short tail offers no strain relief for heavy panel-mounted ports.
Installation notes
Driver installation is required on most operating systems before the virtual COM port appears. The quick-start guide covers the basic steps but does not address unsigned-driver warnings on newer Windows releases. The moulded strain relief is minimal, so repeated connect-disconnect cycles can fatigue the cable at the USB plug.
Highlights
- Connect legacy serial gear via USB
- 30 cm cable keeps workspaces tidy
- Null modem wiring links two DTE devices directly
- Two DB9 screws secure each connection
- Quick-start guide gets you running fast
Specifications
| Brand | StarTech |
|---|---|
| Shipping weight | 2.34 kg |
| Package size | 310 × 241 × 119 mm |
Questions about this item
Should I choose the 30 cm length for my serial setup?
The 30 cm cable keeps the USB-to-DB9 link short and tidy, reducing clutter when connecting a DCE serial device directly to a laptop or desktop port.
What does the USB to Null Modem Serial Adapter actually do inside my computer?
It presents a virtual COM port so legacy DCE equipment such as routers, switches or industrial gear can be managed through a standard USB socket without an internal serial card.
Which USB standard does this adapter use and what throughput can I expect?
The adapter uses a standard USB interface; the practical throughput is limited by the serial device's own baud-rate setting rather than the USB link itself.
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