Not one .......but 50+ years ago I used to hangout with one in his radio shack. His call sign was K4WTF.....wonder if they would assign that one today?
There were a couple of hams on the old CU site.
That call sign, K4WTF, must have expired or the fellow that had it passed away. It has been reassigned to a fellow in FL who requested it since it became available. The fellow that has it now must know what the acronym WTF means.
I used to make regular contacts with a fellow in CA with K6BS as his call sign. He claims that it was randomly assigned.
There was another fellow that I heard on the air that I was afraid to work, N9CUM. I would have requested another call sign if that one were to have been assigned to me.
The call signs are assigned sequentially as they become available. Therefore, they can be just about anything and they will be assigned. In recent years, they have vanity call signs that are old call signs that have expired and become available after a two year waiting period.