'I've been in The Archers for nearly 50 years'

Charles Collingwood has played Brian Aldridge in The Archers since March 1975

Charles Collingwood will have played The Archers' "hard-headed farmer and soft-touch dad" Brian Aldridge for 50 years next March.

Being Brian has been a "great privilege" but starring in the BBC Radio 4 soap at all would have seemed a very distant prospect when he played a "dodgy paint salesman" who had wound his way to Ambridge.

Collingwood's wife, Judy Bennett, played Shula Hebden Lloyd from 1971 until earlier this year and so he was familiar with the show when he was asked to play Dave Escott in 1974.

"I was very busy in schools and children's television at the time and so I wasn't one of these actors who was absolutely desperate for work. Judy was already in the programme so I went up to a party, met Tony Shryane, who was then the producer, and I said how much I loved The Archers," Collingwood told BBC Radio Solent.

Collingwood on the farm in 1981, six years into his career as Brian

"[Shryane] said 'you ought to be in it' and I said 'that'll do me' and quite soon after that I played Dave Escott, who sounded terribly like Brian probably."

Escott had a "mild flirtation" with Peggy, then the landlady of Ambridge's local, The Bull, and within a few months had left the village. (June Spencer, who played Peggy, died in November, aged 105.)

But Shryane told him he would be "back on a permanent basis soon", Collingwood said.

Brian Aldridge arrived in March 1975, married Jennifer in May 1976 and he has never left.

Gwen Berryman, who played Doris Archer from 1951 until 1980 (pictured in 1973), gave Collingwood advice when he became a regular Archers actor

Collingwood said: "[The cast was] still Doris and Dan Archer (played by Gwen Berryman and Edgar Harrison at the time). They were quite scary.

"I think I might have called [Harrison] sir.

"Gwen Berryman was a large figure in every way."

Just before going into the studio to play his first scene as Brian, he said Berryman told him: "Charles, come here. I need to have a word with you. It looks like you're going to be in this programme for some time so there are two things you need to know. One, there are no stars in this programme. The Archers is the star."

Noticing that she had her name embroidered in the chair she was sitting in, he said he "let that one go", adding: "I said 'yes Ms Berryman'.

Collingwood said she continued: "And the other thing is, you're going to be asked to open fetes. Always charge the maximum."

Does he charge the maximum? "Too right!"

The Archers' producer Tony Shryane, pictured in 1958, gave Collingwood not just one but two roles in the show

Collingwood, who lives near Horndean in Hampshire, said The Archers' writers do well to weave storylines that are "fairly comfortable" with others that have real impact.

"They have these big stories. The Rob and Helen story was amazing and did a lot of good. My biggest story – because Brian has always been a womaniser – was my affair with Siobhan and that in many ways altered my profile."

Collingwood appeared on panel shows including Call My Bluff and was even given his own red book by Michael Aspel on This is Your Life in 2003.

"Television is very unforgiving. Television wants it to change every night and be different. So, if you have an affair on a television soap, the chances are you're in love one week, by week six, you're rowing and it's practically over.

"When Brian fell in love with Siobhan it lasted the best part of two years and he had an illegitimate child [Ruairi] and was still running the farm and still married to Jennifer so it had a reality to it."

The cast do not have to learn [scripts] so Collingwood said scenes can last a number of minutes.

"When it was discovered Brian had been having an affair with Siobhan and had a little love child it was Debbie, played by Tamsin Greig, who discovered it," he said.

"I had a scene with Debbie that I think lasted the whole episode. You can't get an actor to learn 15 minutes' of dialogue six times a week, so we're very fortunate."

Brian (Collingwood, centre), pictured in 2007, had a long-running affair with Siobhan (played by Caroline Lennon, right), despite his marriage to Jennifer (Angela Piper, left)

Now 81, like Brian, Collingwood puts his longevity down to "clean living and gin".

He will next year visit Eastleigh in January and the Isle of Wight in February to talk about his life as Brian.

Both events are being held in the afternoon for a reason, he said.

"I'm a realist. The chances are that there are going to be a few who are going to take a bit of time getting out of the car. They're not going to want to pile out at 19:30 on a Sunday, are they?

"If they can have a nice lunch and settle down, I'll lull them to sleep for a couple of hours."