IF YOU WERE down in the dumps, the best medicine you could get would have been to seek out Joaquin Rivera.

"He always had a smile on his face," said longtime friend Diego Castellano, host of the Panorama broadcast on Channel 6. "I never saw him not smiling. And it was contagious. You couldn't talk with him without starting to smile and laugh yourself."

Joaquin Rivera, a popular musician in the Puerto Rican community who was rarely seen without a guitar around his neck, a counselor at Olney High School and an active community leader, died Sunday of a heart attack. He was 63 and lived in Frankford.

"He was an icon," Castellano said. "Every time there was an event that called for music, he was there."

Joaquin was such a well-known figure that he is featured in a mural of Latino musicians on a wall at 5th and Somerset streets in North Philadelphia.

Castellano is going to play tapes of Joaquin performing his music for the next few days on his TV program.

"It will give people one last look at him," Castellano said. "That's the magic of television."

Joaquin led a musical group called "Los Pleneros del Batey."

"Plenero is a musician who plays a Puerto Rican genre of music called plena, and del batey means 'from our back yard,' " Castellano explained.

"He was respected for keeping our culture alive, keeping our music alive," Castellano said.

In addition to his music, Joaquin had a way of spreading good cheer with his ebullient personality.

"He lit up a room," Castellano said. "There would be a group of people at some gathering and he would walk in. Suddenly everyone was surrounding him, laughing and smiling."

Joaquin grew up in Puerto Rico. He loved the music he heard from childhood and yearned to play it. He wanted a guitar, but couldn't afford to buy one.

Finally, after dropping out of school in the sixth grade, he went to work as a waiter for about $11 a week. He was able to buy his first instrument for $16.

He cherished that guitar so much he actually slept with it, he told Daily News reporter Regina Medina in a 2007 interview.

In 1964, Joaquin moved to Philadelphia from the mountain town of Cayey, Puerto Rico. He started out working in a factory that made laminated fabric, took English courses at night and began studying for his GED.

He also took courses at Community College of Philadelphia and Rutgers University. He then went to work at Olney High as a bilingual counselor. He worked for the school district for more than 30 years.

"He has made a difference here in Philadelphia," Roberto Santiago, then-executive director of Concilio, told the Daily News in 2007. "He comes to a new place, incorporates himself, contributes to the city, takes it upon himself to play folkloric music and brings it to the community."

In November 2007, Concilio gave Rivera its Lifetime Achievement Award.

As reported by Regina Medina, Joaquin's group got a thrill while performing at Harvard University when salsa musician and social rights advocate Ruben Blades, a Harvard Law School graduate, sang with them.

"We were really happy and were surprised that Ruben Blades sang with us and shared a good time with us, eating with us and singing with us," Joaquin told the Daily News.

Joaquin married his wife, Maria, in 1971. He also is survived by a son, Joaquin Jr.; two daughters, Inez Rivera and Brenda Masino; three brothers, Julio, Antonio and Victor; two sisters, Ani and Lucila Rivera, and three grandchildren.

Services: Funeral Mass 10 a.m. Saturday at Christ Church and St. Ambrose, 600 W. Venango St. Friends may call at 6 p.m. Friday at the John F. Givnish Funeral Home, 10975 Academy Road, and at 9 a.m. at the church. Burial will be in Greenmount Cemetery, Front and Luzerne streets.