Question about nighttime MW stations

[atrainradio]

This might sounds funny, but are there any MW stations that, instead of powering down at night or completley signing off, they switch to a different frequency, like what they do on the shortwave?

[rdla4]

The only one that I am awre of (in North America) is WNZK, (Near Detroit MI) which is on 680 day and on 690 night. ( maybe the other way around). To my knowledge. WNZK is the only MW station in North America that broadcasts on split channels.

Back several years ago, The Canadian Station CHYR, ran on 710 day and 730 at night. I think that station is nowon FM