Launched in 1996, Online Media's second set-top box (STB) was the STB-20, an advanced networked computer designed to provide an interactive TV station in the home. These machines required high-capacity networks to operate and were limited mostly to trials in selected areas. The STB-20 was used in trials with Cambridge Cable.

Online Media was established as a subsidiary of Acorn Computer group in August 1994 to develop products and services for the networked multimedia market. Online Media produced intelligent set-top boxes for interactive TV applications. The STB1 was Online Media's first set top box.

The STB-20 was based around the ARM7500 processor, with 32MB memory. It ran RISC OS 3.61, a version specific to this set-top box. It had the internal Acorn project name Falcon which can be seen on the circuit board. These machines feature hardware MPEG decoders, as well as an infrared remote for controlling it. There were two variants of the STB-20 available, one with CD-ROM, the other without.

The Cambridge Interactive TV (iTV) trial began in September 1994 with 10 "tame" users and a couple of content providers using the existing Cambridge Cable network. The trial was later expanded to 100 real users and a number of schools. The Cambridge Cable network was upgraded to extend fibre optic cable to the street-side boxes and coaxial cable used in the local loop to individual premises. The upgraded network used ATM (Asynchronous Transfer Mode) to provide full two-way broadband capabilities at up to 2 Megabits per second. Content providers during the trial included the Post Office, Anglia TV, IPC Magazines, Tesco, NatWest bank and the BBC.

When Acorn was broken up in April 1999 the set top box business was sold to Pace Micro Technology for £200,000.

This example in our collection has a model number of 80-STB20-00103239, and was kindly donated by Netherhall School, Cambridge. The remote control is missing from the STB-20 in our collection.