One in the ear from Clive Sinclair

British inventor Sir Clive Sinclair has gone back to his roots with his latest invention - the Sinclair X1 Button Radio, the size of a 10p coin. The X1 weighs half an ounce and is worn in one ear. Tuning involves pushing tiny buttons that "search" up and down the VHF spectrum.

"It will enable you to listen to your favourite station wherever you are, and so discreetly that even the person next to you will be unaware that you are using it," says Sir Clive. He talks of more new products in the pipeline, including another radio, a cordless phone, and a new kind of portable computer. "We've got some exciting new technology that's quite radical in design. My feeling is that portable computers at the moment are too much of a compromise, so we're looking into ways of achieving a better balance between portability and function," he says.

His first invention was a kit radio, the Micromatic, launched in 1964, but Sinclair made his name in the Eighties with the ZX series of personal computers. So where did the X1's name come from?

"Just out the air really," he says. "I'm always calling things X this and Z that, and it's the first of a new range. Startling originality, isn't it?"

The X1 costs £10 including VAT, postage and packing, and is available from Sinclair Research (01933 279300).