You are generalizing again. There was no "trend".One thing I noticed on these boards and elsewhere, some/many of the Top 40 stations in the big markets in the 1960s, like KRLA or in places like Tampa and Tulsa, were on smaller stations, or at the end of the dial.
KUDL 1380 was a pathetic signal in Kansas City, but then WHB entered.
The big "full service" stations, the ones that later went to talk, played music, but not "teen music," or didn't focus on that.
This wasn't everywhere, but I see a trend.
The first Top 40 stations in New York City were WMCA on the marvelous 570, along with 1010 and 1050, both 50 kw. Then, WABC with its non-directional 50 kw came into the race nearly a decade after Top 40 was created.
Cleveland had Top 40 on what was a very decent signal at the time, 1300. Then we got WHK on 1420, another decent signal back then. 1100 with 50 kw tried Top 40 but could not compete. Then we got WIXY 1260, another high band 5 kw station but it did just fine.
Look at Dallas with 1190 competing with 1480 in Dallas and 1360 in Ft Worth. McLendon's 610 in Houston, 920 in El Paso and 550 in San Antonio were excellent signals. So was his 790 in Louisville.
KUDL was adequate to cover the local survey area, but Todd came in with much better formatics and execution. KUDL was just not as good.
KRLA in that era was a great signal. As good or better than KFWB and then KHJ.
Tampa had WLCY on 1380 which was an adequate signal for the size of the market back then. Remember, markets were not expanded by Hooper and Pulse, and Arbitron with its wider methodology did not become prevalent until well into the 70's. In the early 60's, it did not even exist!
WEAM-1390 in DC was also adequate until Arbitron expanded the market and WPGC-FM took over. KOBY-1550 and KEWB-910 and KYA-1260 did just fine in San Francisco until a better signal at 610 came on with Tom Rounds and Bill Drake.
Philly had 560 and 990. Heck, one was so big I even had a dog named "wibbage" back then.
Miami always had the beautiful 560 signal of WQAM. Jacksonville got two good ones at 600 and 690. Denver had Cecil's good signal at 950, and Salt Lake had a nice signal at 1320.
Scooter Seagraves programmed a powerhouse in Tulsa at KAKC-970, so I do not know why you think it had a bad station.
I could go on, but there are plenty of good signal AMs that did Top 40 in the 50's and 60's at a time when the geography of markets was very tight... often less than even the home county.

