Beep! A Brief History of UK Paging — and How to Build Your Own Transmitter Before smartphones, before SMS, before push notifications — there was the pager. For three decades, paging networks formed the invisible backbone of British communications, keeping doctors on call, field engineers reachable, and a generation of teenagers mysteriously popular. This talk traces the arc of paging in the UK, from the launch of the first commercial paging service by British Telecom in the 1950s through to the golden era of consumer paging in the 1980s and 90s. We'll look at the major networks — PageOne, Vodafone & BT — and the protocols that underpinned them: POCSAG, the workhorse standard developed at the Post Office Research Centre, and FLEX, Motorola's higher-speed successor. We'll touch on why paging quietly outlasted the first wave of mobile phones in critical sectors, and why a small but dedicated community still relies on them today. Then we get hands-on. Using an ESP32 and an SX1262 LoRa module — total cost under £15 — I'll demonstrate a working POCSAG transmitter built entirely with open-source tools like RadioLib. We'll send a real message, to a 30 year old pager and show how it can be useful today.