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curious if anyone here thinks big signals are worth it?

I can certainly see how the more spread out the population is, the bigger signal you need, hence why in the original post I suggested two quite different power levels for two different markets. A translator from Cougar Mountain doesn't hit Edmonds with any more than a DX signal, but in Portland the population is a bit more evenly distributed which would make a smaller signal just as workable. ABQ also has a huge haat advantage, as putting a maxed out translator on Sandia Crest would really get out. There are certainly signals I would advise against downgrading. One such signal is KPQ-FM, licensed to Wenatchee WA. That's the only class C in the market, and with its transmitter at the height it is, it covers pretty much all of Eastern Washington.

Trying to set power levels based on current reality is dangerous.

Part of the destruction of AM was caused by the FCC (aided by legislators concerned with monopolistic station owners) not allowing high power at all in the US. So "big" stations were limited to 50 kw, and the commission believed that 5 kw was adequate for big city coverage and 250 watts for smaller ones.

As cities grew in the post-WW II era, that resulted in many stations with very defective coverage of their larger markets. The FCC did not look at future growth.

Similarly, FM's were allocated... particularly after the early 60's reviews of the table of assignments... based on the receiver technology... particularly drift (AFC was yet to come) and selectivity... of the moment. Separations are extreme, and because of that, protections are too severe for adjacent channels. Nearly all the rest of the world allows full power every other channel.

Allowing higher FM power and less separation would have better served the markets.
 
The 50 kW / 150 meter max for the Northeast and most of CA based on 54 dBu protected service areas did a fine job of hamstringing stations in major metros. On the other hand it may have made suburban FMs more viable.
 
As cities grew in the post-WW II era, that resulted in many stations with very defective coverage of their larger markets. The FCC did not look at future growth.

What the FCC did instead was over-license the spectrum, throwing in smaller stations in every available hole, instead of improving the bigger facilities. From the FCC view, they don't benefit by keeping the number of stations the same. The more stations, the more license fees they collect. So now we have a bunch of 1K daytimers that don't have a pot to pee in. Or there are 5K in-city stations such as KABC and KQV, whose target audience now lives far outside the signal range. They're money pits, some with four tower arrays that eat up tons of real estate. Not a good situation for anyone stuck with one.
 
What the FCC did instead was over-license the spectrum, throwing in smaller stations in every available hole, instead of improving the bigger facilities. From the FCC view, they don't benefit by keeping the number of stations the same. The more stations, the more license fees they collect. So now we have a bunch of 1K daytimers that don't have a pot to pee in. Or there are 5K in-city stations such as KABC and KQV, whose target audience now lives far outside the signal range. They're money pits, some with four tower arrays that eat up tons of real estate. Not a good situation for anyone stuck with one.

The two, three and four towers regional stations were largely earlier assignments. Later, we started seeing upgrades and new stations with up to a dozen towers as stations tried to improve coverage of expanding markets.

The worst thing on the FM side was Docket 80-90 which allowed stations to become "portable" resulting in many cities with many more stations and no more revenue.
 
Well, they really aren't always that portable, unless you OWN all the stations you want to move in, and can shuffle them around, including COLs, like a chess game. The strict adherence to the second and third adjacent allotment distances, plus the insistence on keeping First Local Service for nearly nonexistent communities, which are already served by 15 or more city grade signals, and when there are thousands of other equal or superior COLs without a station, it makes little sense. The rural initiative is equally perplexing, especially since these stations are often not economically viable, and many are going off the air. Even the move ins with marginal signals in the center of population are suffering.

Where multiple de facto COLs are attempted to be served by Class C1s, Class C0's, and Class Cs in generally sparsely populated areas, and grandfathered superpower stations 30 miles or more from several population centers, they might be better served by two or three Class As in the population centers, and they could operate with much lower power bills. Maybe the Class As could operate on the same channel or an adjacent channel in some cases.
 
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Well, they really aren't always that portable. Unless you OWN all the stations you want to move in, and can shuffle them around, including COLs, like a chess game.

There are hundreds of cases of groups of FM stations all being moved to different channels so one single station could upgrade.

In Puerto Rico, a station that wanted to move from one of the offshore islands to the mainland caused about 6 different stations to have to move. None wanted to... and they got very little compensation for the technical expense and nearly nothing to promote their new frequencies.

There have been more shuffles in the more populated areas of Texas to allow move-ins than you can shake a tower at. Most were involuntary and not desired by the dozens of affected stations.

There have been many more of these, mostly in areas with large rural areas with assignments that are nearly worthless.

The biggest issue with 80-90 was that it changed the way an A could upgrade to a B or C; previously, it allowed competitive applications but after Bonita Springs, one could both move and upgrade in class with no license loss risk.

The strict adherence to the second and third adjacent allotment distances, plus the insistence on keeping First Local Service for nearly nonexistent communities, which are already served by 15 or more city grade signals, and when there are thousands of other equal or superior COLs without a station, it makes little sense.

True in congested areas, like the Northeast. Not so true in the Midwest, South and West. Look at Tallahassee pre-Docket 80-90 and today. A good market became a bad market with too many stations and no new revenue.
 
FM developed in a haphazard manner because of the reasons the early stations sought FM stations, plus the constantly changing rules. The original contour based allotment rules, and even Class Bs only protected to 1 mV/m, made more sense, and similar rules are still used on NCE-FMs, and are used in Canada and I assume Mexico and other countries. While the NAB practically had a conniption when Section 73.215 was proposed, it ended up being one of their favorites when they found they could use it to their advantage. That and all the other changes that allowed moves for the powerful owners.

In the early days, large cities with stations with a lot of money, often when shared with coowned TV revenues, and big TV towers, most grabbed up the FM frequencies available. In smaller communities, Class IVs, Daytimers, and areas with poor conductivity, were often the first that applied for FMs. Smaller cities with better AM facilities did well enough that they didn't see a reason to apply for an FM, and it was soon too late to do so when the rules became more restrictive, including the Section 73.207 Distance Separation Requirements. This had the effect of giving many stations de facto "clear channels" often not duplicated for 200 miles or more. A few Class Cs and cities with many Class Bs had a HUGE allotment footprint.

I remember when fairly low power Class Cs with antennas on short AM towers, often precluded cochannel and adjacent channels with a ridiculous allotment footprint. WCEN-FM Mt. Pleasant, MI comes to mind. People trying to move and improve their signals on cochannel and adjacent channels and IF restricted channels, complained that WCEN-FM "affected every allotment facility from here to Seattle". This despite a severely short spaced cochannel Class B in Holland, MI. An exaggeration, but consider that the 16 kW/180 foot facility prevented new cochannel facilities for 170 to 180 miles, first adjacents to 105 to 150 miles, and second adjacents to 65 miles, and even IF restrictions to up to 30 miles. Docket 80-90 and further changes certainly improved that situation.
 
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In the early days, large cities with stations with a lot of money, often when shared with coowned TV revenues, and big TV towers, most grabbed up the FM frequencies available.

But assuming that that happened in every market, in the 60's when most markets did not have independent TV stations, just 3 FMs at the most went to TV operators. In many cases, not all TV stations wanted radio. A good example was Cleveland, where two stations got FMs but WEWS (TV) did not. In the 60's, in that market (which had been in the top 10 through the prior decade), half of the FMs were independent, several owned by independent AMs (WDOK, WJMO, WHK) and two by TV operations.

The ones that upgraded the earliest were the independents in that case.
 
The old Section 73.213 with the short spaced zones benefitted those stations that were initially Class Bs with 20 kW (or even grandfathered superpower) on short AM towers the most. Those are the ones that ended up very short spaced when they upgraded to 50 kW/500 feet or near that under newer rules. The ones you always hear about most in Michigan are 102.7 in Mt. Clemens and 102.9 in Ann Arbor. 102.7 is now WDKL, and they recently moved much closer to WWWW on 102.9. WWWW lost its tower site, and had to move further away with a shorter tower, but now they are more short spaced than ever.

Despite what managers say about which is the short spaced station, they are mutually short spaced, and usually because of the ever changing FCC rules. They were fully acceptable at the time they were first authorized.
 
The 1970s world of commercial FM that only allowed two power classes didn't serve listeners well. Docket 80-90 changed that, and allowed FM to become a more robust service to the public..


Of course, how 80-90 was implemented may have left a lot to be desired for broadcasters.

"Daisy-chain" apps...seems like we may have seen the last of those.
 
In smaller markets I'm told that daytimers and Class IVs applied for FMs mostly so another operator didn't get the allocation. Some fMs remained CPs that weren't built for quite awhile




But assuming that that happened in every market, in the 60's when most markets did not have independent TV stations, just 3 FMs at the most went to TV operators. In many cases, not all TV stations wanted radio. A good example was Cleveland, where two stations got FMs but WEWS (TV) did not. In the 60's, in that market (which had been in the top 10 through the prior decade), half of the FMs were independent, several owned by independent AMs (WDOK, WJMO, WHK) and two by TV operations.

The ones that upgraded the earliest were the independents in that case.
 
The 1970s world of commercial FM that only allowed two power classes didn't serve listeners well. Docket 80-90 changed that, and allowed FM to become a more robust service to the public..


Of course, how 80-90 was implemented may have left a lot to be desired for broadcasters.

There were three classes, A, B, C but only two in an individual zone. And then there are the Puerto Rico B's which are still 50 kw, but at 300 meters.

The allowance of sub-types such as C, C1, C2 allowed for better use of the spectrum, but Docket 80-90 over-radioed markets, particularly small ones, to the point that in many places nobody made money and services like news and community activities died.
 
The 1970s world of commercial FM that only allowed two power classes didn't serve listeners well. Docket 80-90 changed that, and allowed FM to become a more robust service to the public..


Of course, how 80-90 was implemented may have left a lot to be desired for broadcasters.

"Daisy-chain" apps...seems like we may have seen the last of those.

The DXing was fun though. A lot of stations signed off at 10 PM, 11 PM, or Midnight. You could have nested stations capturing cochannels. The station that signed off at 10 revealed the next strongest, and when they signed off at 11 the third strongest cochannel was right there.

BTW, has anyone else noticed that new directional gain FM receiving antennas are no longer available anywhere I looked? Is someone scalping them on eBay?
 
Before there were A, B, and C, there were just A and B. A was 1 kW/250 feet and B was 20 kW/500 feet, with provisions for superpower in sparser areas. There were dedicated Class A and Class B channels, if you are too young to remember. As you might recall, WJFM in Grand Rapids, MI was once 500 kW, and is still the most powerful FM station in the US at 320 kW. Popular Communications claimed that if the Earth and Moon were aligned a certain way, you could have heard WJFM on the Moon!
 
There were three classes, A, B, C but only two in an individual zone. And then there are the Puerto Rico B's which are still 50 kw, but at 300 meters.

The allowance of sub-types such as C, C1, C2 allowed for better use of the spectrum, but Docket 80-90 over-radioed markets, particularly small ones, to the point that in many places nobody made money and services like news and community activities died.


Indeed...I over-simplified my earlier post!
 
Before there were A, B, and C, there were just A and B. A was 1 kW/250 feet and B was 20 kW/500 feet, with provisions for superpower in sparser areas. As you might recall, WJFM in Grand Rapids, MI was once 500 kW, and is still the most powerful FM station in the US at 320 kW.

And it took the FCC about two decades to realize that those very low power levels were part of the reason why FM never worked.

Other reasons: Sarnoff, the Armstrong patents, lack of AGC for FM and large size of any combined AM/FM receiver.
 
And it took the FCC about two decades to realize that those very low power levels were part of the reason why FM never worked.

Other reasons: Sarnoff, the Armstrong patents, lack of AGC for FM and large size of any combined AM/FM receiver.

Back in the early 1960s, the General Motors Information Rack Service had a publication called "Something New To Listen To" when they introduced AM-FM radios in cars, and the new Wonder Bar, the first Seek and Scan system. They said that FM range was limited to 10-20 miles, and of course, H Only Polarization didn't help, and soon stations went to separate H and V Polarized antennas by adding V Bays.

They gave a real life example of how a strong city station captured a weak suburban station (which showed an artist drawn sign showing WIBC-FM as the strong station, Delco being based in Kokomo, near Indianapolis). One was on 93.1 and one was 94.7! So that showed some of the problems with FM receivers at that time.
 
Here's the link to the GM Information Rack Service publication on eBay. The image of the page passing the 93.1 WIBC tower capturing 94.7 (not shown, but WFBM-FM/WFBQ, but in a different location far enough away for 93.1 to capture) is the fourth thumbnail image. Click on it and you can read it. Don't know if David has this publication on his site. I have one somewhere, but I don't know if I can find it.

https://www.worthpoint.com/worthopedia/vintage-general-motors-rack-pamphlet-1749405853
 
Well, this has turned into a much more interesting thread than I ever thought. I don't imagine overload would be reduced if signals are weakened in the I suggest? Here in the Portland market, lots of the population gets overload from the big signals, and I'd imagine that markets like Seattle are actually an exception since those towers are on the outskirts of the market.
 
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