But it doesn't work like that any more, and it is thanks to two people in particular that everything changed. The first is Steve Wright, who made the familiar leap from local to national radio in the early Eighties, and rapidly rose through the R1 hierarchy until he reached the afternoon slot. But there he stopped, not because he had reached the ends of his abilities (from the off it was clear he was the most inventive DJ on the station since Kenny Everett) but because he was happy where he was. For the best part of a decade, Steve Wright in the Afternoon was R1's most recognisable and most successful show. Yet because it was not in the flagship slot at breakfast, drawing in listeners for the rest of the day, it gave the station a curious, lopsided feel.
Eventually, after many years of trying, Wright's boss persuaded him in 1994 to move to breakfast-time. But by then it was too late. Wright's once radical "zoo" format had become tired, and he only lasted six months before going off in time-honoured fashion to pursue his ambitions on TV. As is traditional (Everett and Noel Edmonds are the glowing exceptions here) his television career quickly stalled, but Wright has not followed the usual, parallel path into radio obscurity. He is now on Radio Two, where his massively popular weekend shows have helped to make the station the most listened-to in Britain, ahead of the previous and seemingly unchallengeable holders of that accolade, R1.
The second person to shake up R1's comfy and rather complacent career structure never appeared on the station at all. Her name is Kara Noble, and during the period that Steve Wright was changing the face of afternoon radio, she was helping Chris Tarrant to revolutionise breakfast broadcasting on London's Capital Radio. Initially there to read weather and traffic reports, Noble gradually became part of one of the most successful double acts on British radio, and she was able to give Capital two things that R1 lacked. First, a familiar woman's voice in the mornings, which amazing as it now seems, was a complete novelty. And second, as both a foil for Tarrant's jokes and a pinprick for his ballooning ego, she introduced to Britain something of the sound and style of the best of American radio, as exemplified by Howard Stern and his sidekick Robin Quivers, recently seen playing themselves on screen in Stern's Private Parts. Before Noble, it was considered sufficient for a British breakfast jock to appear on air accompanied by nothing more than his trademark gimmick - Tony Blackburn and his double entendres, Noel Edmonds and his ghastly prank phonecalls, Mike Read and his guitar. After Noble, it was clear that R1's DJs were going to need livelier company.
Kara Noble now co-hosts her own award-winning breakfast show on the easy- listening Heart FM, one of the many stations to have sprung up since the Eighties, when R1 was able to do more or less what it liked and still enjoy a captive weekly audience of more than 20 million. As competition has grown and the listening figures have fallen, so the station has had to carve out a distinctive new identity for itself at the indie end of the market. But it has never managed to solve the early-morning headache Wright and Noble created for it. Many permutations have been tried, but in their different ways they have all failed.
Initially, the answer seemed to be to copy Capital by pairing Simon Mayo with the chirpy Sybil Ruscoe (now of Radio Five Live), which though it worked reasonably well for a while, was too much like a pale imitation of the real thing. Then there was the abortive stint by Steve Wright, and after him Mark Goodier with an even feebler "zoo" format. And then came the station's supposed saviour, Chris Evans.
Evans's arrival marked a new tactic in the battle for the breakfast audience, with R1 using its name and kudos to poach stars from television beyond the reach of almost all its competitors. But although Evans got listening figures to go up, his boss, Matthew Bannister, soon discovered that the bigger the star, the harder it was to get him to do what you wanted. So R1 held on to its audience for a while, but it couldn't hold on to Evans, who left when his request to take Fridays off was turned down. Evans is now taking over the breakfast showon Virgin Radio (where he'll have Fridays off). His replacements on R1, meanwhile, the late- night specialists Mark Radcliffe and Mark Riley, have had to go because they couldn't hold on to Evans's audience.
This week, they are replaced by Kevin Greening and Zoe Ball. With the number of listeners now below 10 million for the first time and still falling, these two may represent R1's last throw of the dice. However, there are signs that the station may finally have found the answer to its breakfast nightmare. Greening is an old-fashioned disc jockey who has come up the old-fashioned way from local radio, and through the ranks at R1. He is probably the best, and certainly the sharpest presenter the station now has.
Meanwhile, Zoe Ball represents the station's demographic dream, simultaneously the queen of children's TV and a prize pin-up in the new men's magazines. Her recruitment continues Matthew Bannister's rather curious policy of reversing the old adage about "a great face for radio" by taking people who look the part on TV and sticking them behind a microphone. It didn't work for Emma Freud or Dale Winton or Lisa I'Anson. But Bannister may have learned his lesson. Zoe Ball is not being expected to do it by herself. She is the name, but it will be Greening's show, and in his capable hands she might just get the chance to shine.
Breakfast radio is a ruthless medium. The competition is fierce; and though the listeners are bleary, they are also raw and easily put off. The presenters are liable to be raw at that time of the morning too, and with a minimum of two hours of airtime to fill, there is nowhere to hide. Chris Evans couldn't conceal the petulance that has since become his trademark, while Mark and Lard simply couldn't conceal how much they hated getting up in the morning. But Greening is breezily professional and Ball is professionally breezy. The secret of breakfast radio is to find the best presenters and fit them to the best format. R1 have sometimes had one and sometimes the other. This time they must be desperately hoping that they have got both.
Zoe Ball and Kevin Greening present their first breakfast show on R1, tomorrow, 7-9am. Chris Evans will be on Virgin from tomorrow, 7-10am.