The "Scanners" books have been consistent bestsellers, being the UK's leading guides to the short wave radio equipment employed by enthusiasts to monitor the VHF/UHF wavebands used by airfields, the maritime and emergency services and latterly RT and mobile telephone networks. Radio basics and aerial principles do not change much, but the equipment and the frequencies are ever-changing, hence the comprehensive updating by: the very latest equipment to use; getting the best from the technology; mobile and base monitoring; monitoring trunked and encrypted transmissions; and, decoding radio signals using personal computers with scanners.