The question being: "Why didn't KFRC continue to dominate if hilly terrain was the reason for their dominance?" Also, I thought they were #4 or 5 when they added "The Game Zone".
Semoochie:
First, signal. It's not an all-or-nothing proposition. There are parts of the Bay Area where some FM signals have issues. And it varies by where you are and which station we're talking about.
It's not the same problem as existed in the 1970s and before, with drifting FM signals and multipath issues. The introduction of multipath rejection and phase loop locking in FM radios---especially FM car radios---cured a lot of that and made FM competitive.
The book where KFRC beat everyone---even KGO---was April/May 1978. Here's the SF top ten in that book:
1. KFRC-AM (Top 40): 8.4
2. KGO-AM (Talk): 7.6
3. KSFO-AM (A/C): 6.5
4. KCBS-AM (News): 5.8
5. KFOG-FM (Beautiful): 4.4
6. KIOI-FM (A/C): 3.9
7. KABL-AM (Beautiful): 3.5
8. KSFX-FM (Disco): 3.4
9. KNBR-AM (A/C): 3.3
10. KDIA-AM (R&B): 3.2
Worth noting that KABL-AM had a 3.5 while KABL-FM had a 2.4. KSFO's numbers were inflated by having Giants baseball (they were a 3.8 in the winter book).
Also, hilly terrain wasn't the
entire reason for KFRC's dominance. It was one helluva radio station (as was KGO at the time). But the hilly terrain kept would-be competitors from investing in talent and promotion for their FMs at the level that would allow them to succeed in any significant way against KFRC. They largely chose lower-cost formats or formats that worked well in homes, stores and offices, where they didn't have to hit moving receivers.
But the walls were cracking----look at KIOI. In that winter book where KSFO got a 3.8? K-101 had a 3.7. And KNBR had a 3.0. So that format (A/C) was beginning to see significant impact from FM.
As for The Game Zone: KFRC launched that on April 18, 1985. The winter '84/'85 Arbitron was already out. Here's the top ten (eleven because of a tie):
1. KGO-AM (Talk): 8.8
2. KCBS-AM (News): 5.3
3. KYUU-FM (some called it A/C, some called it CHR): 4.1
4. KIOI-FM (same as KYUU---if these were A/C, they were very hot A/Cs): 3.5
5. KSOL-FM (R&B): 3.4
6. KABL-FM (Beautiful): 3.3
7. KSAN-FM (Country): 3.2
8. KFRC-AM (CHR): 3.1
9. KNBR-AM (A/C): 2.8
10. KFOG-FM (AOR): 2.7
10. KRQR-FM (AOR): 2.7
At first glance, that doesn't look too bad for KFRC. But clearly, contemporary music listening had moved to FM. KFRC and KNBR were the only AM music stations in the top ten.
Also, format changes rarely happen on the spur of the moment. You can bet RKO thought long and hard about The Game Zone before pulling the trigger.
KFRC was below a 3 share two books in a row before that winter 3.1---a 2.6 in summer of '84 and a 2.7 in fall. That 2.6 had KFRC in 13th place. The ranking improved to 9th in the fall '84 book, but it was only a 0.1 increase---KFRC went up in ranking because other stations did worse---and they weren't the stations KFRC was competing with.
Did the Game Zone hurt KFRC? Oh, hell yes---it was only on for half of the April/May '85 book and it sent the station crashing to a 1.9. But was KFRC in a situation where they just could have left it alone and it would have recovered? Nah.
Frankly, my suspicion has always been that Walt Sabo's real intention was to flip KFRC to standards all along. He was already offering his services to other stations with his approach to the format. And when RKO finally decided to go for it in August of 1986, it was his format they used.
