Presgraves, 65, of Oak Ridge Drive, joined the television station in January 1970 after eight years doing sports on WHAG radio as well as holding a full-time job as a post office clerk.
He spent his first 22 years on air doing the evening sportscasts before being promoted about five years ago to the morning news, including live spots during "The Today Show."
He will continue for two more weeks to host the five-minute public affairs program "Today in the Valley," which airs toward the end of "The Today Show" on Sunday through Friday.
His stint with Saturday morning's "Track Side" will end with the finish of the racing season in November.
Presgraves will probably be remembered most for his sportscasts, which included interviews with Mickey Mantle and Joe DiMaggio.
As a childhood Yankee fan who admired DiMaggio, Presgraves said he was awestruck interviewing the Yankee Clipper, who was in town about 10 years ago for a Hagerstown Suns game.
Such interviews are some of Presgraves' fondest on-air memories, but he still remembers the station's first days when it was still a struggle.
The station was laughed at in the early days when mistakes occurred on air as everyone got their bearings and dealt with what was then archaic equipment, Presgraves said.
What is now a computer-generated scoreboard for the day's sports scores used to be a magnetic board, he said. Occasionally a magnetic number would fall off the board while the camera was panning down the scores, Presgraves said.
"I think we've come a long way in 27 years," Presgraves said.
While people had come to know him through their living rooms for years, Presgraves said he still wondered what kind of reaction he would get when he served as grand marshal of the Mummers' Parade about 15 years ago.
People were genuinely pleased to see him, said the mild-mannered journalist.
They still are.
After a mild heart attack in March 1996 that kept him off the air temporarily, Presgraves received hundreds of cards and several phone calls from concerned friends and viewers, he said.
"It was overwhelming," he said.
"When you're down and out that certainly does help your spirits."
Presgraves has given back to the community over the years.
Hugh Breslin, vice president and general manager, said Presgraves has helped untold thousands of folks through his charity work.
Presgraves has conducted telethons for the last 14 years for charities such as United Cerebral Palsy, the Parent-Child Center and Easter Seals.
Breslin said Presgraves would be recognized on air during the week leading up to his Oct. 3 retirement. He also was recognized during the station's 25th anniversary two years ago.
News Director Bob Borngesser described Presgraves as a loyal and dedicated employee who had given a large part of his life to the station and the community.
It is the chance to meet members of the local community that Presgraves said he will miss the most in his retirement.
But, the avid racing fan isn't planning on moving to Florida to retire.
"I'm going to live right here. I grew up here. My roots are here," said the 1950 Hagerstown High School graduate.
The first thing Presgraves said he will do when he retires is smash his alarm clock.
Since he began the 6:30 a.m. broadcast, Presgraves has been rising out of bed at 2:45 a.m.
Besides sleeping in, Presgraves plans to spend more time with his nine grandchildren and do some traveling. He and his wife, Elaine, have three children.
Presgraves will still be on the scene at local sports events, but will no longer have to rush back to the downtown office to go on the air.
"I can just go on home after a game now."