JY1 was an enigma. When a radio ham from Nottingham put out a general call during a radio festival in the early 1970s, a man calling himself Hussein, with the call sign JY1, responded. That he claimed to be Jordanian was clear enough from the first two letters. But who, from a nation that used two or three digits as its call signs, would be audacious enough to list themselves as number one? The radio ham was confused. 'He thought that nobody has a call sign of just one digit, so he thought it was a pirate,' explains Henry Balen, of Beeston in Nottinghamshire, whose friend (who has since died) had put out the call. 'He told whoever it was claiming to be JY1 to get off the air in language that I couldn't repeat.' But the amateur radio fanatic, whom Balen's friend had sent off with such profanity, was none other than his majesty King Hussein bin Talal of Jordan, the most famous amateur radio enthusiast in the world.

'King Hussein was a proper gentleman and explained to him why his call sign was just number one. Because, as the King, he was number one in his country, and the gentleman was very embarrassed.' When he wasn't making war, brokering peace or running his own country for almost half a century, the late King Hussein was often scanning the airwaves for friends, as if he were in broad- casting's earlier version of an Internet chat room.

King Hussein was in prestigious company. During his lifetime he could have hooked up with fellow enthusiasts KY2 (his wife, Queen Noor), EA0JC (King Juan Carlos of Spain) and LU1SM (Argentinian president Carlos Menem). And Priscilla Presley is among the other unlikely, though less stately, celebrities who enjoy communic-ating with the world this way. While in death, the King joins the late VU2RG (Rajiv Ghandi) and K7UGA (Senator Barry Goldwater).

But among them Hussein reigned supreme. In 1970, the radio society of Great Britain made him an honorary member. When he came to Britain in 1993 he found time to give an interview to the society's official magazine, Radiocom.

The King made contact with the first radio amateur in space - W5LFL (Owen Garriott aboard the space shuttle Columbia): 'We managed to arrange a schedule with him on his 92nd orbit,' Hussein was reported as saying. 'It was an excellent contact, something like three or four minutes horizon to horizon.' The King operated not only from Jordan but from the United States, Spain, Austria and Canada when he was on the road. He had his own station in Britain, although it was put out of action for some time when the antennae was damaged.

In a letter to the Daily Telegraph yesterday, one reader recalled making contact with a 28-year-old JY1 in 1964. A small group of US Navy personnel on the Aleutian islands were having trouble getting through to the outside world following an earthquake in Alaska. As they searched the radio waves for operators who could establish a link with their families, they came across JY1 in Amman.

'We passed on several messages to JY1,' wrote Marty Baker, 'who duly phoned the families concerned through the normal links. He must have been considerably out of pocket as a result. What a King!' By his own admission, the King was something of a radio addict.

'I try to operate whenever and wherever I can,' he told Radcom. 'I have constructed equipment, but not as much as I would like to.' The former Harrow student, who became a member of the the school's radio society after he was given a Hallicrafters radio, was a regular on the airwaves even in his later years.

'In times of crisis and difficulty, it was a way to keep in touch with friends throughout the world who were able to help relay messages and to secure humanitarian help as well,' he said.

Earlier this week, one retired teacher in Ireland said he was in regular contact with King Hussein. From Beara, a remote area in West Cork on the west coast of Ireland, Bernie O'Sullivan would talk to the King as he sat on his yacht in the Red Sea.

'We were good friends. He used to look for me and I looked for him,' says Sullivan. 'Sometimes we would make contact three or four times, other times it might be once. The contact lasted for about five years, then it sort of fizzled out. The last time I spoke to him was 10 years ago. I think he eventually became too busy for the radio. I was very sad to see him after the chemotherapy - he was a broken man. The two great loves in his life were amateur radio and flying.' Bernie came across the King by accident when he was switching through radio bands in April 1970.

'I heard him speaking to Americans one day on the one of the bands,' Sullivan said. 'His call sign fascinated me because it was very short, just JY1. The letter stood for Jordan and the number one stood for himself. After hearing the broadcast, myself and a load of other European stations called him up.

'He asked to have a word with the Irish station. He knew that because my call sign started as EI. He used to just give his name as Hussein. There are no titles with radio hams. That's the beauty of our radio - there is no class distinction. It was just Hussein and Bernie.'