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Overpowered FM Stations in San Francisco

G

Gregg.

Like Los Angeles, many of the FM stations in San Francisco are over-powered. Nearly all of California is a Class B zone, except for some rural communities in the north. That means 50,000 watts maximum at 500 feet (152 meters). You can have a taller tower, but that would result in a corresponding drop in power.

However, most Bay Area FM stations have power and/or antenna heights far above the Class B limits. Either they were established before these rules were in place. Or the FCC allowed them to get past these regulations as what happened in Los Angeles. Note that KQED-FM was granted 110,000 watts when it signed on in 1963. KMEL (then KFRC-FM) went on the air in 1961 and is now powered at 69,000 watts. In 1961, KIOI went from 30,000 watts to 125,000 watts. Why did the FCC set rules and then allow so many stations in LA and San Francisco to exceed them? Most stations in San Diego, San Jose, Fresno and Bakersfield seem to follow the Class B limits, with just a few exceptions.

107.7 KSAN Classic Rock - Cumulus - 8,900 watts - 1,161 feet ... This is correct.

106.9 KFRC All-News (KCBS simulcast) - Audacy - 80,000 watts - 1,001 feet ... Overpowered.

106.1 KMEL Urban - iHeart - 69,000 watts - 1,281 feet ... Overpowered.

105.3 KITS Alternative Rock - Audacy - 15,000 watts - 1,201 feet ... Slightly overpowered.

104.5 KNBR-FM Sports - Cumulus - 7,100 watts - 1,506 feet ... Slightly overpowered.

103.7 KOSF Classic Hits - iHeart - 6,400 watts - 1,322 feet ... This is correct.

102.9 KBLX Urban AC - Bonneville - 7,200 watts - 1,270 feet ... This is correct.

102.1 KRBQ Classic Hip Hop - Audacy - 33,000 watts - 1,047 feet ... Overpowered.

101.1 KIOI Hot AC - iHeart - 125,000 watts - 1,161 feet ... Very overpowered.

100.3 KBRG Latin AC - Univision - 14,500 watts - 2,579 feet ... Overpowered.

99.7 KMVQ Top 40 - Bonneville - 40,000 watts - 1,299 feet ... Overpowered.

98.9 KSOL Regional Mexican - Univision - 6,100 watts - 1,342 feet ... This is correct.

98.1 KISQ Soft AC - iHeart - 75,000 watts - 1,016 feet ... Overpowered.

97.3 KLLC Modern AC - Audacy - 82,000 watts - 1,014 feet ... Overpowered.

96.5 KOIT Adult Contemporary - Bonneville - 24,000 watts - 1,570 feet ... Overpowered.

95.7 KGMZ Sports - Audacy - 6,900 watts - 1,289 feet ... This is correct.

94.9 KYLD Top 40 - iHeart - 30,000 watts - 1,211 feet ... Overpowered.

94.1 KPFA Public Alternative - Pacifica - 59,000 watts - 1,329 feet ... Overpowered.

93.3 KRZZ Regional Mexican - SBS - 6,000 watts - 1,362 feet ... This is correct.

92.3 KSJO South Asian - Silicon Valley Asian Media - 32,000 watts - 446 feet ... This is underpowered.

88.5 KQED-FM NPR Public Radio - KQED Inc. - 110,000 watts - 1,270 feet ... Very overpowered.
 
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Gregg. said:
Like Los Angeles, many of the FM stations in San Francisco are over-powered. Nearly all of California is a Class B zone, except for some rural communities in the north. That means 50,000 watts maximum at 500 feet (152 meters). You can have a taller tower, but that would result in a corresponding drop in power.

However, most Bay Area FM stations have power and/or antenna heights far above the Class B limits. Either they were established before these rules were in place.
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They were established before the current allocations tables and rules were established in 1962 (IIRC). The Bay Area had early adoption of FM, despite the terrain issues in the region.

KSJO had to reduce power in the early 2000s when then-Clear Channel was doing a "trimulcast" with 92.1 Walnut Creek and 92.7 Alameda, for the purpose of reducing prohibited overlap.

And let's not mention some of the short-spacing that also resulted.

In any event, "overpowered" seems a judgmental term to me - yes, many Bay Area FMs go beyond current maximums but that's a stroke of luck for them - we would now call it "first mover advantage" - and may even help mitigate some of the terrain-related coverage issues...sometimes. That doesn't always work, which is why there are the boosters in the Diablo Valley and Pleasanton, and why there's KPFB simulcasting KPFA.
 
A bit of both. In other Class B areas, we see an occasional station grandfathered above the standard Class B power. In Boston, you have WGBH-FM at 100,000 watts but everyone else conforms, including plenty of stations that have been on the air since the start of FM broadcasting. In Columbus, WNCI is 140,000 watts, but everyone else is 50,000 watts or less.

Yet in San Francisco and Los Angeles, only a handful of stations follow the Class B rules. It's not like those two California cities put FM stations on the air before folks in New York, Chicago and Philadelphia thought about it. Yet most Eastern and Midwest cities have no overpowered stations that come to mind, while nearly all the LA and SF stations are well over the Class B limit.
 
Gregg. said:
Yet in San Francisco and Los Angeles, only a handful of stations follow the Class B rules. It's not like those two California cities put FM stations on the air before folks in New York, Chicago and Philadelphia thought about it. Yet most Eastern and Midwest cities have no overpowered stations that come to mind, while nearly all the LA and SF stations are well over the Class B limit.
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It's easy to forget that FM was something of a wasteland in the 1950s and 1960s except in a few locations. Even after more FM stations came on the air in the early and mid 1960s, coverage was still spotty. I didn't even hear an FM radio until 1968, when a station that was more or less local to me (KRXL) finally came on the air. In much of the Midwest, FM's growth spurt didn't happen until the 1970s. Until Docket 80-90, many class C's didn't operate with anything near full facilities. This was less of an issue with class B facilities in Zone I due to the lower limits.

The "class B rules" - "limits" is a more accurate term - don't apply fully to stations on the air on or before 1962.
 
Gregg- I see your point now, thanks. As you know, there was a deadline, late 1964. Other than that, I think it was less about timeline and more about circumstances and perceived need. 10 KW from a central location in a NE city may have been fine. It may also have been about the shape of the city back then and proximity of other towns and cities.

San Francisco may have realized early on that the market was huge and elongated. That meant Mount San Bruno, and Bruno required ERP and many stations were able to make it happen.

Let's take a moment for what the late Herb Caen had to say about Sutro Tower:
"I keep waiting for it to stalk down the hill and attack the Golden Gate Bridge"
 
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Gregg. said:
Yet in San Francisco and Los Angeles, only a handful of stations follow the Class B rules. It's not like those two California cities put FM stations on the air before folks in New York, Chicago and Philadelphia thought about it. Yet most Eastern and Midwest cities have no overpowered stations that come to mind, while nearly all the LA and SF stations are well over the Class B limit.
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The big difference in both LA and SF is the availability of high mountains (Mt. Wilson and Mt. San Bruno) to mount antennas.

Putting 10kW or 20kW into an antenna on top of a mountain at 1500ft HAAT is much more economically feasible than putting up a 1500 ft tower would be in Chicago.
 
Craig, you need to actually come out here from New York and experience the terrain and signal issues that necessitate higher powers. For example, KQED is, as you mentioned, pumping 110 Kw from Mount San Bruno, about 20 miles from my house. That should be enough juice to pick up their signal on my fillings. But there's a hill right up the street, and because of it I get the Sacramento NPR station (KXJZ) much better from certain rooms. Just about 90 minutes ago, I was listening to Weekend Edition, and they had a segment about Latino music. KQED was blending to mono on my radio, but KXJZ, which is 100 miles away and on the other side of a couple of mountain ranges, was being received in glorious stereo. That's not an anomoly, not tropospheric ducting, it's a regular occurrance. Can you sit in your house or apartment and pull in a Hartford or Philly station regularly? Probably not.

Another example is KGMZ, a sportstalk station at 105.7. You can write that 6.9 Kw @ 1289 feet is "correct", but there's a reason they keep losing (in the ratings) to KNBR, which you say is "slightly overpowered" at 7100w@1506'. And it's not that the Bay Area likes our Giants better than it likes the Warriors. It's just easier to receive KNBR in a lot of places, and where it isn't they're backstopped by the legacy 50Kw omni signal on AM 680.

It's just a different ballgame out here. Or to put it another way, you can't compare apples to wine grapes.
 
Indeed, for nearly every engineer, terrain in many western towns and cities has to be experienced first hand to appreciate.
Out west, I learned really fast to listen closely to what native market engineers said about local signal propagation.
Actually, respect the locals everywhere, because propagation is affected by the local environment.
"Good morning heartache" could have been written about ducting in the Southeast.
 
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So. What's the big deal. Superpower stations exist. Many (but not all) of these stations are only this way because we have Zones I and I-A. If the entire country was one FM zone (or California was not in Zone I-A), then many of these stations would be C1, C0 and C. Some would still be over the 92 km service contour or the 100 kW power for Class C, but many of the superpower stations nationwide fit into an existing service class mold if the C classes were used in these areas.
 
Exactly, I agree Kelly A and Michi. The super-power FMs were permitted or in compliance when licensed. Thus far, stations are permitted to continue operating with licensed facilities that have not been modified beyond subsequent policy for grandfathered facilities. There are AM stations out there still broadcasting on paper licenses with file numbers beginning with two letters, like BL

But you knew that :)

I am fine with it because it represents history and continuity. And sometimes means a very interesting transmitter site.
 
Kelly A said:
Exactly. Seems like an attempt to sensationalize something that isn't.
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Yes. No one has suggested that superpower stations aren't compliant with the rules as they existed when originally licensed with their present facilities. They're an interesting quirk of history. No one is being harmed by their existence.

There are more important things to discuss, like whether an EDM format will be the salvation of AM radio. Or something.
 
Weiserguy said:
Craig, you need to actually come out here from New York and experience the terrain and signal issues that necessitate higher powers. For example, KQED is, as you mentioned, pumping 110 Kw from Mount San Bruno, about 20 miles from my house. That should be enough juice to pick up their signal on my fillings. But there's a hill right up the street, and because of it I get the Sacramento NPR station (KXJZ) much better from certain rooms. Just about 90 minutes ago, I was listening to Weekend Edition, and they had a segment about Latino music. KQED was blending to mono on my radio, but KXJZ, which is 100 miles away and on the other side of a couple of mountain ranges, was being received in glorious stereo. That's not an anomoly, not tropospheric ducting, it's a regular occurrance. Can you sit in your house or apartment and pull in a Hartford or Philly station regularly? Probably not.
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At my Oakland location, I was just a few blocks from the top of the ridge that separates Orinda, Moraga, and Canyon from Berkeley and Oakland. I could catch a couple of Sacramento stations from my house before closer LPFMs blocked them (96.9 KSEG, 102.5 KSFM), and in my driveway, KSFM and KDON would duke it out for supremacy on my car radio. But at the top of the ridge, a lot more from the east came in.

Also not often noted is the large number of relatively low-wattage NCE FMs, some of which get out quite far with just 500 watts. KZSU from Stanford is a good example; I could get it easily on just about any radio in the house even with just 500 watts. KCEA and KFJC had similar properties. Yet I could never get a clear signal from KPOO in San Francisco - though I could see San Francisco from my bedroom window - and KDFC (ex-KUSF)'s stereo signal was always noisy and weak. On the other side of the ridge, there was KSMC from Moraga, which provided not a peep just a few blocks down the ridge.

Weiserguy said:
Another example is KGMZ, a sportstalk station at 105.7. You can write that 6.9 Kw @ 1289 feet is "correct", but there's a reason they keep losing (in the ratings) to KNBR, which you say is "slightly overpowered" at 7100w@1506'. And it's not that the Bay Area likes our Giants better than it likes the Warriors. It's just easier to receive KNBR in a lot of places, and where it isn't they're backstopped by the legacy 50Kw omni signal on AM 680.

It's just a different ballgame out here. Or to put it another way, you can't compare apples to wine grapes.
Click to expand...
KFOG KNBR-FM is also on the Sutro tower; KGMZ is on Mt. San Bruno. That makes a difference, too.
 
Weiserguy said:
Another example is KGMZ, a sportstalk station at 105.7. You can write that 6.9 Kw @ 1289 feet is "correct", but there's a reason they keep losing (in the ratings) to KNBR, which you say is "slightly overpowered" at 7100w@1506'. And it's not that the Bay Area likes our Giants better than it likes the Warriors. It's just easier to receive KNBR in a lot of places, and where it isn't they're backstopped by the legacy 50Kw omni signal on AM 680.

It's just a different ballgame out here. Or to put it another way, you can't compare apples to wine grapes.
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I think you meant 95.7 for KGMZ.

And radio signals can act in unique ways...
 
Most of the Michigan superpowers were (and are) intended to serve multiple markets. 93.7 WBCT (320kW) and 105.7 WSRW (265kW) broadcast from separate towers about halfway between Grand Rapids and Kalamazoo, which are in separate radio markets but the same TV market. Incidentally, both WBCT and WSRW were originally co-owned with TV stations
 
Negin said:
I think you meant 95.7 for KGMZ.

And radio signals can act in unique ways...
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I did mean 95.7, thank you. Funny how I'd proofread what I wrote, and completely missed that oopsie. (105.7 is KVVF, the San Jose station that used to be "KARA in Santa Clara" when I first moved here. 50 Kw @ 499', definitely positively absolutely conforming according to @Gregg's criteria.)
 
Gregg. said:
Like Los Angeles, many of the FM stations in San Francisco are over-powered. Nearly all of California is a Class B zone, except for some rural communities in the north. That means 50,000 watts maximum at 500 feet (152 meters). You can have a taller tower, but that would result in a corresponding drop in power.

However, most Bay Area FM stations have power and/or antenna heights far above the Class B limits. Either they were established before these rules were in place. Or the FCC allowed them to get past these regulations as what happened in Los Angeles. Note that KQED-FM was granted 110,000 watts when it signed on in 1963. KMEL (then KFRC-FM) went on the air in 1961 and is now powered at 69,000 watts. In 1961, KIOI went from 30,000 watts to 125,000 watts. Why did the FCC set rules and then allow so many stations in LA and San Francisco to exceed them? Most stations in San Diego, San Jose, Fresno and Bakersfield seem to follow the Class B limits, with just a few exceptions.

107.7 KSAN Classic Rock - Cumulus - 8,900 watts - 1,161 feet ... This is correct.

106.9 KFRC All-News (KCBS simulcast) - Audacy - 80,000 watts - 1,001 feet ... Overpowered.

106.1 KMEL Urban - iHeart - 69,000 watts - 1,281 feet ... Overpowered.

105.3 KITS Alternative Rock - Audacy - 15,000 watts - 1,201 feet ... Slightly overpowered.

104.5 KNBR-FM Sports - Cumulus - 7,100 watts - 1,506 feet ... Slightly overpowered.

103.7 KOSF Classic Hits - iHeart - 6,400 watts - 1,322 feet ... This is correct.

102.9 KBLX Urban AC - Bonneville - 7,200 watts - 1,270 feet ... This is correct.

102.1 KRBQ Classic Hip Hop - Audacy - 33,000 watts - 1,047 feet ... Overpowered.

101.1 KIOI Hot AC - iHeart - 125,000 watts - 1,161 feet ... Very overpowered.

100.3 KBRG Latin AC - Univision - 14,500 watts - 2,579 feet ... Overpowered.

99.7 KMVQ Top 40 - Bonneville - 40,000 watts - 1,299 feet ... Overpowered.

98.9 KSOL Regional Mexican - Univision - 6,100 watts - 1,342 feet ... This is correct.

98.1 KISQ Soft AC - iHeart - 75,000 watts - 1,016 feet ... Overpowered.

97.3 KLLC Modern AC - Audacy - 82,000 watts - 1,014 feet ... Overpowered.

96.5 KOIT Adult Contemporary - Bonneville - 24,000 watts - 1,570 feet ... Overpowered.

95.7 KGMZ Sports - Audacy - 6,900 watts - 1,289 feet ... This is correct.

94.9 KYLD Top 40 - iHeart - 30,000 watts - 1,211 feet ... Overpowered.

94.1 KPFA Public Alternative - Pacifica - 59,000 watts - 1,329 feet ... Overpowered.

93.3 KRZZ Regional Mexican - SBS - 6,000 watts - 1,362 feet ... This is correct.

92.3 KSJO South Asian - Silicon Valley Asian Media - 32,000 watts - 446 feet ... This is underpowered.

88.5 KQED-FM NPR Public Radio - KQED Inc. - 110,000 watts - 1,270 feet ... Very overpowered.
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How about KRUZ Santa Barbara 105 kW at almost 3000 ft HAAT, and KPFK Los Angeles 110 kW at almost 3000 ft HAAT ! KRUZ is 4000 ft above sea level, and KPFK is nearly 6000 ft above sea level. I believe these two stations have the greatest "predicted" coverage of all stationa in CA.
 
I know this is SF Radio board, but someone mentions about Los Angeles Superpower FM stations.

107.5 KLVE Spanish AC - Uforia Audio Network - 29,500wtts 2998 ft Overpowered

106.7 KROQ Alternative - Audacy Radio - 5,600wtts 1338ft Correct Power (Transmit from Flint Peak)

105.9 KPWR Rhythmic CHR - Meruelo Radio - 25,000wtts 3,035ft Overpowered

105.1 KKGO Country - Mt Wilson FM Broadcasters - 18,000wtts 2,890ft Overpowered

104.3 KBIG Hot AC - iHeartMedia -65,000wtts 3,045ft Overpowered

103.5 KOST AC - iHeartMedia 11,500wtts 3,114 ft Overpowered

102.7 KIIS CHR/Pop - iHeartMedia 8,000wtts 2,959 ft Overpowered

101.9 KSCA Regional Mexican - Uforia Audio Network - 4,800wtts 2,831ft Overpowered

101.1 KRTH Classic Hits - Audacy Radio 51,000wtts 3,133ft Overpowered

100.3 KKLQ Contemporary Christian Music - EMF 5,400wtts 2,916ft Overpowered

99.9 KOLA Classic Hits Anaheim Broadcasting Corp 29,500wtts 1,663ft Overpowered (Can be heard in Los Angeles)

99.5 KKLA Christian Talk - Salem Media - 10,000wtts 2,959ft Overpowered

98.7 KYSR Alternative - iHeartMedia - 75,000wtts 1,180ft Overpowered (transmit from Mt. Lee (Hollywood Sign)

97.9 KLAX Regional Mexican Spanish Broadcasting System -33,000wtts 604ft Correct Power (transmit from Glendale)

97.5 KLYY Spanish Adult Hits Entravision 72,000wtts 1,827ft Overpowered (Can be heard in Los Angeles)

97.1 KNX-FM News - Audacy Radio - 21,000wtts 3,002ft Overpowered

96.3 KXOL - Spanish Rhythmic CHR - Spanish Broadcasting System - 6,600 1,306 ft (Correct Power) Transmit from Flint Peak Used to be grandfather @ 54kw/147M.

95.5 KLOS - Album Oriented Rock - Meruelo Radio - 63,000wtts 3,130ft Overpowered

94.7 KTWV - Rhythmic AC - Audacy Radio - 58,000wtts 2,9831ft Overpowered

93.9 KLLI - Spanish Rhythmic CHR - Meruelo Radio 18,500wtts 3,009ft Overpowered

93.1 KCBS-FM - Adult Hits - Audacy Radio 27,500wtts 3,524ft Overpowered

92.3 KRRL - Urban - iHeart Media - 42,000wtts 2,910ft Overpowered

91.5 KUSC - Classical - University of Southern California 39,000wtts 2,923ft Overpowered

90.7 KPFK - Variety - Pacifica Foundation 110,000wtts 2,831ft Overpowered

89.9 KCRW - NPR News/AAA - Santa Monica College - 6,900wtts 1,109ft Correct Power Transmitting from Mt. Lee (Hollywood sign)

89.3 KPCC - NPR News/Talk - Pasadena City College - 600wtts 2,923ft Correct Power

88.1 KKJZ - Jazz - CSU-Long Beach 30,000wtts 449ft Underpowered Transmitted from Signal Hill in Long Beach
 
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