You know him as the onetime host of “That’s Incredible!,’’ “Hollywood Squares,’’ and occasionally “The Tonight Show’’ when Johnny Carson was on vacation. But there’s another side of John Davidson.

The guy with the great hair who was an omnipresent TV personality in the 1970s and ’80s wants to be taken seriously as a troubadour and he’s got a gig July 16 at Club Passim, the venerable Cambridge club where the likes of Joan Baez, Bob Dylan, and Joni Mitchell have performed.

“My brother graduated from Harvard and when I went to visit him, he’d take me to this little folk club,’’ Davidson says of Passim, which was then called Club 47. “It’s one of the major folk clubs in the country and I decided I should try to play there. So I called up and said, ‘Would you every consider letting this TV variety host perform?’ and they said sure.’’

The whole time Davidson, 74, was hosting “The $100,000 Pyramid’’ and singing to blue hairs in Vegas ballrooms backed by an 18-piece orchestra, he was dreaming of sitting on a stool with an acoustic guitar. Who knew?

“I would like to have that credibility, the ability to say I played at Passim,’’ says the West Bridgewater product who lives in Lenox now. “This is very important to me.’’

Clearly. But how did a guy with ambitions of being another Tom Rush end up as a game show host who’s been on both Broadway and “Love Boat’’?

“I’ve had a confusing career. I had a manager early on who told me to be a pitchfork instead of a spear. Tony Bennett is a spear, Johnny Mathis is a spear,’’ Davidson says. “In other words, they had one prong. I wanted to use all my prongs.’’

At the show at Passim, he’ll play guitar and sing a mix of folk, country, Americana, and a few tunes from the Great American Songbook.

“When you play Vegas, you have to do a certain type of show,’’ he says. “The Passim audience is more intelligent, more discerning, more wanting to find out who this guy really is. I can’t wait.’’