POP / Prat's the word that crops up most

Jonathan King is 50. He brought us 'Una Paloma Blanca', 10cc and Genesi s. Martin Kelner forgives him

''Prat is the word that crops up most,'' says Jonathan King helpfully. He has guessed that the radio programme I am preparing to celebrate his 50th birthday might possibly fall short of outright eulogy. Looking at the evidence for the prosecution, and, more painfully, listening to some of it as well - ''Una Paloma Blanca'', ''Leap Up and Down (Wave Your Knickers in the Air)'', ''Lick a Smurp for Christmas'' by Father Abraphart - I feel he may be right. The wonder is, in view of these and other horrors, that the cuttings yield nothing stronger than ''prat''.

In truth, though, it is difficult to be anything more than mildly irritated by Jonathan - he's such a cartoon character. Just as Tom might throw Jerry into the food blender without the mouse coming to any harm, you feel the songs Jonathan demolishes, and the people he attacks, will straighten out fine after a few minutes.

The comic likeability of J K, as he likes to call himself, so disarms you that you tend not to notice his blatant, shameless self-promotion. It was J K, he reminds me within 20 seconds of our meeting, who discovered and named Genesis. Ditto 10 cc (45 seconds). When barely out of his teens he was running Decca Records. His own UK record label in the 1970s was one of the most successful independent labels ever. His Entertainment USA achieved some of BBC 2's biggest ever ratings, says King. And he has a rather good English literature degree from Cambridge (two minutes and 50 seconds).

By far his greatest achievement, though, has been to persuade the public and a section of the music industry that his views are incredibly important. King's last major hit record, remember, was nearly 20 years ago, yet here he is: ''millionaire pop pundit Jonathan King'', on the leader page of the Daily Express castigating commercial radio for its vile music and brainless presenters; ''pop megamouth Jonathan King'' in the Sun urging John Birt to quit before he wrecks the BBC; ''trenchant'' Jonathan King on the why-oh-why page of the Daily Mail telling George Michael to stop whingeing and grow up.

''If it moves, slag it off. That's my motto,'' says King. ''I give them good copy. When I did the Bob Geldof thing in the Sun, the paper got 18,000 letters of protest. That's the kind of reaction papers like.

''If you ask me,'' he continues, in that characteristically animated rush, ''I am sure Geldof went into Band Aid and Live Aid with impeccable motives. But then if somebody phones up offering you 60 grand to do a milk ad on the back of it, that's when you should jump off the bandwagon. Bob didn't, and he is now an important TV executive running The Big Breakfast and Don't Forget Your Toothbrush. I could not appear on any of his programmes. My conscience wouldn't let me.''

''Jonathan is always entertaining to read and listen to,'' says John Peel, ''but I suspect his actual contribution to the music business has been greatly exaggerated, mostly by himself. Sure, he discovered Genesis, 10 cc, and the Bay City Rollers. If you have been around as long as Jonathan and myself, you are bound to make the odd discovery - though most of them would have made it without you. Little tends to be said about all the acts we discovered who sank without trace. On balance, though, I think it is rather encouraging he is still around at 50 and people still go to him for advice, although there is no evidence any of it turns out to be terrifically valuable.''

In April next year we will be able to judge the value of King's advice for ourselves. He has convinced someone at the BBC that the way to shake the annual Song for Europe contest out of its 1970s rut is to hand it over to someone who understands pop music. Someone like himself who had a whole string of hits in the . . . er . . . 1970s. And J K is, coincidentally, that man. There is a view that King has hijacked the song contest as another vehicle to promote J K. The contrary view is that he really loves pop music, that he cares about the three-minute pop tune more deeply than anyone in Britain today.

''You've just got him neatly filed in the column marked 'wally' and self-serving wally at that,'' says Andy Kershaw, ''when the phone rings in the studio on a Sunday night, and it's Jonathan King wanting to know all the details of the demo tape you have just played and how he can get in touch with the artist. He does seem genuinely interested in promoting new music.''

J K could, one supposes, live quite comfortably without ever listening to another pop song as long as he lives. He owns the publishing rights to the early 10 cc hits, as well as a percentage of their earnings after leaving his UK Records, plus a slice of the first Genesis album. And then there are the royalties for his own first big smash hit ''Everyone's Gone to the Moon'', written when he was 19, and covered by artistes as diverse as Percy Faith and Nina Simone. Every time anyone performs those deathless lines, ''Parks full of motors, painted green / mouths full of chocolate-covered cream'', it means another tank of petrol for J K's Roller.

So, isn't it a little sad, at 50, to be going out to pop concerts on his own, or sitting at home on a Saturday night listening to Andy Kershaw?

''Some people would see it as sad,'' says King. ''To them, happiness is having a family, but I've never wanted that. Music is really what excites me, still, and I'm never happier than when I'm discovering something new. For instance, in the Tipsheet, a photocopied information sheet we sell to music business people, we have been tipping a record by Rednex called ''Cotton Eye Joe''. Now it has started selling in huge quantities. It could be No 1 for Christmas. That makes me happy, and I have no financial interest in it at all.''

And so he moves it along. J K is one of those people - like Jimmy Savile or David Frost - who keeps an interview bubbling along brilliantly while revealing little about himself. We talk about his awful records - and his one brilliant record, ''Hooked on a Feeling'', that ug-a-chugga arrangement of a B J Thomas country song, a version of which is used in Reservoir Dogs. He tells me a dreadful joke about Michelangelo (his ceiling was something for him to fall back on).

You can't help liking him. All right, some of his records do fall into the crimes-against-humanity category, he did release a version of ''I Can't Let Maggie Go'' when Margaret Thatcher retired, he did write the lyric ''When I was a young boy / Women gave me no joy. / Then I grew in stature, You caught me looking atcha'', and the ''opinions'' he is paid by the tabloids to express do not really bear close analysis. But . . .

As John Peel puts it: ''His music is, by and large, ghastly. His opinions are sometimes vaguely irritating, but more often just irrelevant. He's a marginal figure in the music world. I'd call him a maverick but he'd probably enjoy that too much. However, as a human being, I tend to give him the thumbs up. I'm always pleased to

see him.''

- 'Jonathan King at 50' is on Radio 2, 6pm, Saturday, 10 Dec

(Photograph omitted)