You never knew her name but if you listened to CHUM in the 60s, you almost certainly heard her voice. Trella Hart was the vocalist on some of those famous PAMS jingles that played before songs on Top 40 radio stations across North America in the 60s and 70s. 

"Hart’s distinct voice and laughter became a signature across radio stations that used PAMS’ “Swiszle” and “Fun Vibrations” packages, of which the latter was most famously used on New York City’s 77 WABC. She later extended her talents to commercial jingles and other production companies, including JAM."

I know they're no longer really in favour, but I loved those 60s jingles because they were exclusive to one station to a market (in Toronto, CHUM had many of their packages) and they're are as much a part of what made radio back then so great as the music itself.

You can hear her vocals on these famous PAMS jingles. 

And did you know that Hart actually released a single? It came out in 1970, but only reached #120 on Billboard's Bubbling Under chart. Which is why those 10 second I.D.s will forever be her legacy for 60s radio listeners.