An eccentric personality, Mieuli eschewed formal attire and conservative grooming in favor of a casual wardrobe and his ever-present full beard and deerstalker.
His association with the 49ers led him to land the team's star fullback, Joe "The Jet" Perry, on his own sports and music radio program, "Both Sides Of The Record", sponsored by Burgie, on R&B-formatted KWBR (1310 AM; later known as KDIA) beginning in 1954.
He subsequently produced Giants radio broadcasts, hosted by Russ Hodges and Lon Simmons upon the team's move from New York by owner Horace Stoneham in 1958.
(The San Francisco Giants' 1962 season highlights, narrated by Russ Hodges and Lon Simmons and produced by Mieuli, were released on a long-playing record by Fantasy, catalog number GB-1962.)
Mieuli, along with 32 other local investors, was part of a joint venture headed by Diners Club that purchased the Philadelphia Warriors from Eddie Gottlieb for $850,000 and moved the ballclub to the Bay Area following the 1961–62 NBA season.
[7] Mieuli played a major role in breaking down racial barriers in the NBA by encouraging his team's front office to sign players regardless of color.
[10] Ten of the twelve players on the Warriors' championship roster during the 1975 Finals were African American, as was head coach Al Attles and his assistant Joe Roberts.
In addition to his role with Franklin Mieuli & Associates, which handles broadcast engineering for thirty pro and college sports teams, he was an active member of the San Francisco chapter of Broadcast Legends, and was inducted into the National Television Academy/Northern California Chapter's Gold Circle in 2006, honoring him for his significant contributions to local television during a career spanning more than fifty years.