Those old Zeniths had a reputation as "hot" performers on the AM broadcast band. They are prized today by collectors and Dx'ers alike.I grew up with a Zenith Royal-1000 radio. DX'ed all the shortwave bands on it, but I really had a lot of fun on MW band. I grew up (and still live) just outside of NYC in northeast NJ and my favorite AM was WABC. I was an avid listener from 1973 (I was 9), until they went all-talk in 1982. But, as much as I enjoyed listening to WABC I had a lot of fun DX'ing the AM band. I only wish that I had kept logs of what/when I heard various stations. All I can say for sure is that I heard stations from all over the east coast and midwest. WABC was definitely big-time radio, the stations I heard while DX'ing had that small-town sound that appealed to me. I guess that sound is one of things I miss about Top 40 on the AM band. I still DX the AM band, but it's not quite the same.
I agree about DX-ing the band today. It gets tedious, as the stations largely sound alike with their syndicated political/religious/sports talk formats. At least WABC devotes a few hours each weekend to its music radio heritage.