Fred M. Sloniker wrote:

Some years later, I decided to look up what this dot and dash pattern
might mean, in hopes of determining what I'd been listening to. I'd
heard of CQ, so I thought it might turn out to be that, but no...

-... ..-.

That's 'BF', isn't it? Why would someone be sending 'BF BF BF' out on
a radio frequency? Or was my radio so crap as to be picking up
something else entirely? Please shed some light my way; I'm feeling
lost...

Most likely you heard a low frequency aeronautical beacon. These operate
below the am broadcast band.

I did a quick check and found a few beacons that ID as BF.

They are in Seattle, WA; Bakersfield, CA; Bradford, PA; Cleveland, OH;
and Scottsbluff, NE.

Were you near any of those cities?

Art Harris N2AH