Ukulele Bob tells Debbie Waite why she should not mix up his instrument of choice with a guitar. Or a banjo. And it's most definitely not a toy ...

Ukelele Bob is a little fed-up.

"The ukulele gets treated as a toy, people even mix it up with the banjo!" he tells me indignantly.

I'm a little worried about Bob getting annoyed.

He's 86 and in January he underwent his fourth major heart operation.

"I've had four by-passes," he confides.

"The docs say I'm operating on only one artery. But I feel fit as fiddle, or should I say fit as ukulele!"

Bob Hodson (aka 'Ukulele Bob' ), can't stay annoyed for long. It's not in his nature and besides, he's too anxious to tell me all the exciting things he's been up to in the past 86 years.

I've found the way to his house in Stainfield Road, in Marston, Oxford, because he's thoughtfully hung a ukulele on the front door His wife Dot, 87, fetches me a cuppa and out comes the ukulele for a quick rendition of Sweet Georgia Brown, followed by a little jazz and even a few bars of Mozart.

I say: "I never knew you could play so many different types of music on four strings.

"There's a lot about the ukulele you don't know and that's because it never gets written," Bob chastises.

"It's the Cinderella of strings. I'm forever getting letters from our members (of the Ukulele Society of Great Britain), saying they're fed up with what's 'not written' about the uke.

"The papers talk about George Formby, or Tiny Tim, or George Harrison and, fair enough, George was a brilliant player - but the greats are people like Billy Uke and Andy Eastwood, who is still packing venues as we speak."

I shamefully admit to Bob that I knew as much about ukuleles as I do about banjos - but I'm very interested in Ukulele Bob.

And what a story it turns out to be. Born in New Jersey, USA, he moved to the UK with his dad, who was in the Canadian army and his British-born mum, when he was two and half.

They moved to Oxford and one day in school the teacher asked if anyone could play the ukulele in the Christmas concert. Ten-year-old Bob couldn't, but he put his hand up anyway and persuaded a neighbour who could play to teach him some chords.

"I sat on the end of the stage so no-one could hear how bad I was," he says of his first concert. His dad bought him his first ukulele that Christmas - it was five shillings from Woolworths.

Everywhere Bob went, his ukulele went too.

During the Second World War he was in the Navy and lost two ukuleles 'in action'.

"The first was used as a battering ram by a mate when we were jumped by a group of locals in Ceylon," he recalls.

"I lost the replacement when I was swept overboard from the HMS Ceylon in the Bay of Biscay."

Thankfully he was washed back to ship and rescued, but his ukulele didn't make it. After the war, he formed a concert party, the Topper Tones and later the Oxford TV Show Band which competed on Opportunity Knocks. In between, he supplemented his income working as an artist and also a film and TV extra, including a role in the film Shadowlands, alongside Anthony Hopkins.

A big charity worker, he produced art for the children on the John Radcliffe's children's trauma ward for four years. And he's still the voice behind the kids' show on hospital station Radio Cherwell every week.

"I told you there was a lot to write," the great- grandfather says, as he plays me a little bit of Abba's I had A Dream.

"The ukulele is having a bit of a revival," he reminds me. "We've got 175 members, from 15-year olds up to old guys like me. Last year, £300,000 worth of ukuleles were sold in the UK."

Bob gave me a quick overview of his instrument. There are four strings and four sizes, the soprano, the tenor, the baritone and the largest, the tenor guitar.

He adds in a mock exasperated tone: "Even the Oxford University Press had the definition of the ukulele wrong. In their dictionary they call it a 'small guitar'. I wrote to them and they wrote back, thanking me for the information. But they haven't changed the definition yet!" he says with a smile.