Here in Wood Dale, IL (near NW suburb of Chicago):
Daytime: WTMJ
Nighttime: WTMJ
DX/Retro: In the old days WTMJ was fairly easy to null at night producing some nice DX catches. In 1980's/1990's this frequency was the best bet to hear the state of Vermont on AM here in Chicago area. Heard WVMT (Burlington, VT) few times in those days. Other catches include WSUN (St. Petersburg, FL), WSKQ (Newark, NJ), WHEN (Syracuse, NY), WRJZ (Knoxville, TN), KWFT (Wichita Falls, TX), WAKY (Louisville, KY), WFMV (Cayce, SC), CFCL (Timmins, ON - no longer on the air), CKRM (Regina, SK). Another common station in those days with WTMJ nulled used to be Radio Rebelde from Cuba. I also have several tentative logs of La Voz de Nicaragua back in 1980's, but I could never get a positive ID, so I am not counting it. Once WTMJ increased their power and started using IBOC it became difficult to DX 620 kHz. They stopped using IBOC eventually, but it is still difficult to null them. The most recent catch on this frequency is WJDX (Jackson, MS) in 2023.