Emma Freud rang and said they were making a film about pirate radio, and could I cast my eye over it to see if they’d made any glaring errors? The film has exactly the feeling of rebellion we had at the time. and has little nods to all the DJs of the era.

My only comment was that they made it seem a lot more fun than it really was. I seem to remember spending a lot of time in the record library preparing the show, answering fan mail and sleeping. The working quarters were all on deck level, and they had a flat roof, so you could sunbathe.

It was fine if the sun was shining, but on cold winter nights in high seas, it could be really grim. We’d try not to let that show on air, of course.

Before pirate radio, I was a car mechanic and car salesman, but I did a bit of DJing in bars and ballrooms. My first job was on Swinging Radio England in 1966, but I moved to Radio Caroline after a few months, doing the 9pm to midnight shift — although we’d cover for other guys’ shows, and that meant you’d be on air six hours a day.

It was the perfect apprenticeship, because everything was always going wrong.

At that point, there were three stations — Radio Caroline, Radio London and Radio England — all moored about half a mile from each other. Caroline’s boat, the Mi Amigo, was very, very small. There were eight people working on the station, plus three or four Dutch sailors. We’d have different captains every few months, and having a good time depended how liberal the captain was. On Radio London, there was an Irish DJ who liked his Guinness, and because our crew was Dutch, we’d have loads of Heineken.

If the captain was co-operative, we used the lifeboat to row over to the London and swap crates of beer with them.

When they passed the act outlawing pirates, Caroline kept going. The problem with that was that the daily boat that came out of Harwich with the food, mail and other supplies couldn’t legally set sail, so we had to be supplied from Holland — which could take 24 hours. We’d end up running short of water half the time. It felt incredibly isolated. No mail and just this relentless PR from the BBC as it geared up to launch Radio 1. One night, we’d had enough, and three of us jumped into the lifeboat with a crate of beer and went in as close to the shore as we dared, yelling insults at Harold Wilson. Suddenly, this tiny dot appeared on the horizon and started powering towards us at enormous speed, and we realised it was the coastguard with about 12 men, coming for us. We were chugging back to the 3½-mile limit as fast as we could, and only just made it. So we were giving the coastguard some . . . um, cheery waves, let’s say.

I look back on the pirates with such affection because they really did challenge the state monopoly on radio, which was strangling music, and the four main record companies’ monopoly on artists, which was really conservative and bland. Chris Blackwell set up Island on the back of My Boy Lollipop, and that was just one of the records that wouldn’t have been a hit without the pirates.

Pirate Johnnie Walker, Radio 2, Saturdays, 9-11pm

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