How Did 93.7 and 105.7 Grand Rapids Get Superpowered?

According to Radio-Locator...

93.7 WBCT Grand Rapids...320,000 watts on a 781 foot tower.

105.7 WSRW Grand Rapids...265,000 watts on a 581 foot tower.

Most FM stations in the Class B region of the U.S. (Northeast U.S. from Norfolk to Portland to Milwaukee and also So. California) are limited to apx. 50,000 watts on a 500 foot tower. As the tower gets taller, the power must decrease. So on a 781 foot tower, WBCT should really only run around 17,000 watts. On a 581 foot tower, WSRW should only run around 36,000 watts.

These stations obviously were on the air before the FCC set Class B power and height limits for this part of the country. So they're "grandfathered" at this unusual power level. But running several hundred thousand watts was unusual, even in the infancy of FM. There are plenty of FM stations that signed on in the 40s and 50s without this high power. In fact, most probably ran lower power than they do today.

Does anyone know the history of how 93.1 and 105.7 got this unusual power? Wikipedia says owner John Feltzer actually boosted 93.1's power to 500,000 watts in 1960, although that was later reduced to where it is now. And 105.7, then called WOOD-FM, didn't sign on until 1962, so it really wasn't among the very early FM stations.

So how did both stations get permission to go so high powered? Why two in the same medium market city? And why should an owner pay such an expensive electric bill to reach sections of Michigan and Indiana where his sales staff never visited anyway?

The basics of superpower FM... in the beginning, there was no such thing as Class C. There were Class A stations with up to 1,000 watts at 250', and Class B with up to 20,000 watts at 500'.

However, the FCC rules explicitly stated that Class B applicants outside the Northeast could request a waiver of the 20,000-watt limit. It appears that, if no interference would result, the waiver was generally granted. There was no limit to how much power you could request in a waiver -- to restate that, THERE WAS NO MAXIMUM POWER LIMIT FOR CLASS B STATIONS. (again, you did need to show you wouldn't interfere with anything, and that it was actually possible to build a transmission facility that would generate that much power.)

There were quite a few superpower applications filed -- and granted -- in the early days of FM. Some of them were actually built It looks as if Grand Rapids' 93.7 was the biggest, authorized at one time for 550,000 watts, although there were 540,000-watt stations in Alabama and Iowa. (do remember that a 50,000-watt station was superpower in those days when the nominal limit was 20,000)

FM stations began closing down in the early 1950s. The pre-WW2 FM radios had been obsoleted when the band was moved from 42MHz, and they weren't being replaced in the quantities expected. Listeners -- and stations -- were spending their resources on TV. Some of the superpower stations reduced power (it was expensive to operate a transmitter that big!), others shut down altogether. (as did many more modest stations) In 1950 there were 22 stations left with powers of more than 100,000 watts.

I've got some holes in my understanding of the chronology, but it was in 1964 that the framework of the current rules was established. From that date, no new stations of more than 100,000 watts were authorized. (none of more than 50,000 watts in Class B territory, which includes southern Michigan) Existing stations authorized powers in excess of the limits were permitted to continue. (it should be noted that any area they serve that wouldn't be served if they were compliant with the current rules is not protected from interference)

I believe 93.7's later power reduction was the result of an increase in antenna height.

Why two in the same market? Good question. Actually, there are more: don't forget about 104.1.. There's another big one at East Lansing (WKAR at 85kw) and *four* in Detroit. One thing that's a bit unusual about the Grand Rapids market.. is that the TV towers lie between Grand Rapids and Kalamazoo and serve both cities.. powerful FMs located on those towers could serve both cities as well.. but with FM in the 1950s and 1960s making money primarily on background music subcarriers, extra power would be necessary to make the subcarriers work in the cities. Note that 93.7 and 105.7 were co-owned with channels 3 and 8 respectively, and were on the TV towers. (105.7 has since moved) (that doesn't explain 104.1, which was *not* initially a public station) That's only a guess.

The Channel 3 and 8 towers are too far from Grand Rapids to cover it with 50 kW/500 feet with a 70 dBu City Grade Contour. That's the regulation that required superpower. The secondary benefit was the coverage of Kalamazoo and Battle Creek, and the subcarriers were available over a wider area.

WFGR 98.7 and WTRV 100.5 are two Docket 80-90 Class A stations which actually have better signals in Grand Rapids and the immediate surrounding areas than the superpower stations. The signals have less flutter and I have seen spectrum analyses posted online that show this quite dramatically.

Memphis, was another market with superpowered FM's from the second phase of FM development..

As a side effect, 93.7 and 105.7 also get decent coverage of Lansing. Also, two of Michigan Radio's three stations run on grandfathered power levels (WUOM runs 93kW while WVGR runs 96kW).

Speaking of other cities, almost every major station in Los Angeles and San Francisco runs on grandfathered power.

Out here in Seattle, we only had 1, 105.3 KCMS used to be 240,000 watts, later reduced to 115,000 watts, now runs 54,000 watts from a different tower. W9Y, would you mind updating the list of superpowered fm stations on your website?

Also, 93.7 and 105.7 were sister stations to TV stations (93.7 to Channel 3 and 105.7 to Channel 8). Many early VHF TV stations had FM sisters.

There's no doubt that locating your FM antenna on a coowned TV facility tower was better than putting it on an AM tower that averaged 250 feet. That is one of the big things that differentiated the early facilities. Even WRIF, formerly WXYZ-FM, on the WXYZ-TV tower to this day, is superpowered for a Class B at 27000 watts (quoted as 27200 watts in the early days) at 880 feet. For many years, many Class Bs were valuable assets in the rough, languishing in relative obscurity until Section 73.213 gave them the ability to be at full Class B facilities even though quite short spaced, and omni at less power if they were even more short spaced. For instance, cochannel Class Bs just 125 miles apart, and first adjacents just 80 miles apart were allowed 50000 watts from 500 feet omni. But realize that only a handful of stations in a market had the option of mounting on a TV tower, usually just the three network stations that were VHF, or UHF network stations in markets like South Bend. Since the the third VHF in the Grand Rapids Kalamazoo Battle Creek TV Market, WZZM-TV Channel 13, was almost an afterthought, and it had to be fully spaced to WSPD-TV Channel 13 to get a City Grade signal barely over Grand Rapids, and too far for an FM now after new superpowers were not allowed, resulting in WZZM-FM being mounted for years as 50000 watts from 175 feet on their STL tower in Grand Rapids. Make no mistake, the big owners leaned on the FCC to have those rules to benefit their own stations and leave the rest out of luck. If you just look at David's fantastic archive, you'll see how these situations played out. One term you may want to look up is deintermixture, to see how they kept new VHFs out of markets, even those like WZZM-TV, in other areas. WZZM-TV was forever the third wheel in the market, even requiring a translator in Kalamazoo, and eventually an entirely new UHF ABC facility owned by another company. Similarly, WJRT-TV was kept from serving the Detroit Market. They can talk about COLs all they wanted, but the proposed Clarkston area facilities would have served all of Southeastern Michigan quite well with all required City Grade signals met and LOS into Flint Saginaw Bay City, and the Detroit Market as well. It would have even had a City Grade over much or all of Detroit from Clarkston.

Schroedingers Cat said:

There's no doubt that locating your FM antenna on a coowned TV facility tower was better than putting it on an AM tower that averaged 250 feet. That is one of the big things that differentiated the early facilities. Even WRIF, formerly WXYZ-FM, on the WXYZ-TV tower to this day, is superpowered for a Class B at 27000 watts (quoted as 27200 watts in the early days) at 880 feet. For many years, many Class Bs were valuable assets in the rough, languishing in relative obscurity until Section 73.213 gave them the ability to be at full Class B facilities even though quite short spaced, and omni at less power if they were even more short spaced. For instance, cochannel Class Bs just 125 miles apart, and first adjacents just 80 miles apart were allowed 50000 watts from 500 feet omni. But realize that only a handful of stations in a market had the option of mounting on a TV tower, usually just the three network stations that were VHF, or UHF network stations in markets like South Bend. Since the the third VHF in the Grand Rapids Kalamazoo Battle Creek TV Market, WZZM-TV Channel 13, was almost an afterthought, and it had to be fully spaced to WSPD-TV Channel 13 to get a City Grade signal barely over Grand Rapids, and too far for an FM now after new superpowers were not allowed, resulting in WZZM-FM being mounted for years as 50000 watts from 175 feet on their STL tower in Grand Rapids. Make no mistake, the big owners leaned on the FCC to have those rules to benefit their own stations and leave the rest out of luck. If you just look at David's fantastic archive, you'll see how these situations played out. One term you may want to look up is deintermixture, to see how they kept new VHFs out of markets, even those like WZZM-TV, in other areas. WZZM-TV was forever the third wheel in the market, even requiring a translator in Kalamazoo, and eventually an entirely new UHF ABC facility owned by another company.

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Ironically, speaking of FMs on TV towers, there is an FM now located on WZZM's tower (105.3 WHTS Coopersville, the former 105.3 WCXT Hart which downgraded from C1 to C2 and later upgraded to B when it moved to ZZM's tower) that is consistently top 10 in Grand Rapids despite being 25 miles from Grand Rapids.

I'd have to say that if WHTS is doing that well, it would probably do even better on a signal more centered with the population. Same with WSNX. You can only do so much pseudo superpowering with antenna tower mounting modeling. And an omni facility near the center of population can do the same thing if it is advantageous, neutralizing the effect of "rimshots". Grand Rapids, though not mountainous, has many terrain shadowing problems near various rivers. The near side of a river within a mile or two is shadowed, whereas the far side may not be. When you get to antennas 25 or 30 miles away, these become even bigger problems, even with 320000 watts.