Seven UK companies yesterday agreed a common air interface standard for cordless phone technology. British Telecom, Mercury Communications, Ferranti Creditphone, STC, GEC Plessey, Orbitel and Shaye Communications reached the specification for an open standard for linking pocket phones to radio base stations after weeks of intense negotiations in a race to beat a Department of Trade & Industry-imposed deadline (CI No 1,000). The standard, which consists of three layers of communications protocols has been agreed in principle but details are expected to be finalised by October when it will be presented to the government for perusal although no amendments are expected. The companies say they don’t expect products based on the standard to be delivered until 1990, but propose that manufacturers with early CT2 products using a proprietary air interface be allowed to run them in parallel with the new generation phones so that a Telepoint cordless public phone service can be started sooner. Ferranti Creditphone expects to have products by year-end, and Shaye is believed to be close behind. Whose standard is it? STC says it is not dissatified.