A while back a local station was having a problem and their analog signal was off but they were still transmitting digital. When I tuned in it was kind of funny

A while back a local station was having a problem and their analog signal was off but they were still transmitting digital. When I tuned in it was kind of funny because it was all static and then it faded into whatever music they were playing. I've always wondered what full digital stations do, but for the reasons you've said I doubt there are any.