Stations that don't run full power for their class and HAAT

[ftballfan]

I know of quite a few stations that don't run full power for their class and HAAT.

Off the top of my head, here are a few in Michigan on the commercial band:
WWSS - 95.3 - 17kW/165m (C2) - should be 41kW
WCHY - 97.7 - 3.4kW/152m (C3) - should be 11kW
WEUL - 98.1 - 1kW/142m (A) - should be 3.1kW
WIKB - 99.1 - 60kW/150m (C1) - should be 100kW
WQON - 100.3 - 60kW/131m (C1) - should be 100kW
WHKB - 102.3 - 6kW/167m (C3) - should be 8.8kW
WGFM - 105.1 - 43kW/295m (C1) - should be 100kW
WCUP - 105.7 - 51kW/261m (C1) - should be 100kW

Most noncommercials don't run full power for their class and HAAT (the only exceptions generally being the Class C/C0 stations). And there are worse offenders in other states (I'm looking at stations that run 6.1kW or 26kW from a tower shorter than 100m and those that run 51kW from a tower shorter than 150m).

 

[fybush]

Noncommercial stations are licensed by contour protection, rather than by mileage/class spacing. So it's sort of a backwards thing - if the most you can squeeze in is, say, 27 kW/152 m, that's what you get. The class designation follows from that - since that's more than the 25 kW/100 m of a C3/B1, the station in question would be classed as a C2 or a B, depending on where it's located. The class designation, in this case, is used for only a few very limited purposes, mainly to determine the necessary spacings to commercial stations and to Canada. But it does not imply an ability to upgrade to class maximum.

For a commercial-band station that runs less than class maximum, it's usually because the station is using 73.215 short spacing. There's a set of allotment coordinates where the allocation could be placed at class maximum power/height, but in the real world it makes more sense to place the transmitter somewhere else that may not allow for maximum power/height. Sometimes a directional antenna is used to allow for higher power, but that involves a bunch of compromises, too.

Some of the stations you mention also may be grandfathered in with short spacings. Or they may be in locations where there's just no need to run class maximum power or build a tall tower if all the desired population is closer in.

 

[bobdavcav]

Here's one I don't understand, why do some stations run such high power from low antennas? Examples KMXS/Anchorage, AK 100 KW at 31 M could easily downgrade to a C3 without losing any listeners except maybe in office buildings. There's also a 96.7 in Preston ID that runs 100 kw at 66 meters, they could easily get to a C2 and not even a full one and not lose any coverage, plus wouldn't be shortspaced to KQMB if they are currently. There's also a station in Colorado don't remember the calls that is applying to be a C1 with 100 KW at 64 meters, probably getting a new transmitter on the same tower it's currently using. Again, they could upgrade the antenna height and go C2 without losing any coverage, then they probably can boost to C1 if they wanted.

 

[davideduardo]

Here's one I don't understand, why do some stations run such high power from low antennas? Examples KMXS/Anchorage, AK 100 KW at 31 M could easily downgrade to a C3 without losing any listeners except maybe in office buildings. There's also a 96.7 in Preston ID that runs 100 kw at 66 meters, they could easily get to a C2 and not even a full one and not lose any coverage, plus wouldn't be shortspaced to KQMB if they are currently. There's also a station in Colorado don't remember the calls that is applying to be a C1 with 100 KW at 64 meters, probably getting a new transmitter on the same tower it's currently using. Again, they could upgrade the antenna height and go C2 without losing any coverage, then they probably can boost to C1 if they wanted.

Most of these cases fall into two areas.

First, there are stations with sites that are as much as several thousand feet above the market they serve, but which are surrounded on several sides by even higher mountains... making the average height seem very low. So many of those are really optimum facilities in areas with rugged terrain.

Example: I built HCTM 95.1 with a site that was about 100 meters below average terrain. However, it was over 2000 feet above the market and all the nearby population centers and it was at nearly 4000 meters AMSL. Going any higher would make the altitude issues of transmitter operation too severe and would have required enormous mechanical beam tilt and there would have been ridge effect off the mountain... insurmountable issues where we were limited to a tower of less than 35 meters at most for aesthetic reasons.

The second reason is that available sites that can pour a signal back into the market are not always available. Zoning, NIMBY, public land policy, accessibility, power grid connections, etc., can all be factors. So a station gets as close to a full facility at the best location possible that adequately covers the market.

 

[fybush]

And to add to David's excellent summary, it may be that some of these (I haven't checked) are short-spaced stations. There may be an allocation point somewhere else where a full-class facility would fit, but real-world terrain makes it desirable to locate the actual transmitter somewhere closer to the population base. The station retains the higher class designation based on the allocation coordinates, but operates in the real world with a lower facility that better serves the population it's trying to reach, even though it may not fill the entire allocations envelope.

 

[bobdavcav]

Hmm David, which station? Do you mean KCTM? That would be an interesting one to look at. Scott, they may be ones to look at. Like I said, I can think of KQMB being tightly spaced to this station that I can't remember the calls of. Assuming that there isn't any terrain issues like David mentioned, wouldn't it make sense to just upgrade the tower height without moving the tower? As far as the CO application I referenced, I would assume there are terrain issues there, since CO is mountainous. I wonder what KMXS looks like? Given that Anchorage is about at sea level, there shouldn't be too many issues with altitude. I'll look into these as well.

 

[fybush]

Taller towers are more expensive to build and maintain. If they're above a certain height, they have to be kept painted and lit. In some cases, the FAA won't let a tower go any higher because it would interfere with a flight path. In other cases, local opposition and zoning issues limit tower height.

In general, you go as tall as you need to go to cover the population you're trying to hit...but no higher than that, because at that point you're just wasting money.

 

[Bongwater]

In the early days (and it might also still apply in some cases today), it's "use it or lose it". I've known of stations licensed to higher power outputs than what they were actually using and since they didn't go full power, they are now permanently stuck at their present power levels. Could they move tower sites? Perhaps. But with newer co-channel/1st/2nd adjacent stations popping up closer and closer (and the usual NIMBYS, zoning, FAA/bird flight hazards), that's likely to yield a much WORSE result than where they are now. And likely an even lower power level/HAAT.

 

[bobdavcav]

What's interesting is I took a look at the stations I was thinking of, and the only station that is operating from a lower tower than its haat is KKEX. KMXS operates from a tower 74 meters above the ground, while the other station operates from a tower 72 meters above ground.

 

[davideduardo]

Hmm David, which station? Do you mean KCTM? That would be an interesting one to look at.

No, I meant HCTM, the FM I put on the air in 1966 in Quito, Eucador as northern South America's first FM (other than STL's). The elevation of the city ranged from 9600 to 10,000 feet AMSL, and my site was about 2500 feet above the center of the city on the side of a mountain that continued on upwards to cap out at just under 16,000 feet (thus the negative HAAT for the site).

 

[ftballfan]

Here's one I don't understand, why do some stations run such high power from low antennas? Examples KMXS/Anchorage, AK 100 KW at 31 M could easily downgrade to a C3 without losing any listeners except maybe in office buildings. There's also a 96.7 in Preston ID that runs 100 kw at 66 meters, they could easily get to a C2 and not even a full one and not lose any coverage, plus wouldn't be shortspaced to KQMB if they are currently. There's also a station in Colorado don't remember the calls that is applying to be a C1 with 100 KW at 64 meters, probably getting a new transmitter on the same tower it's currently using. Again, they could upgrade the antenna height and go C2 without losing any coverage, then they probably can boost to C1 if they wanted.

Most Anchorage stations are infamous for this. KASH is the only Anchorage station that runs full power for their class (C1, 100kW/299m). KLEF, probably the worst offender, is licensed as a C1, but runs 25kW/9m (I think a full Class A would get out farther than KLEF does).

 

[bobdavcav]

There's another one that doesn't make sense. Why is KLEF a C1 and not a C3? That erp and haat combination is well within C3 parameters. Here's another one that I really don't understand, coming out of what is turning into a saga that is supposed to be a pretty simple move. Originally, they applied for a 3.7 kw C2 from the KGW-TV tower, 470 meters haat. They later modified that to a C1 with 10 kw at the same haat. Then in February, they applied for a full C1, 57 kw at 387 meters. So far this makes some sense, but then there's this one just applied for today, 9.7 kw at 472 meters. Stonehenge can't be that far away from the KGW tower, I think it's only about a mile or so, Scott you can correct me on this, I've never even been to our own towers here in Seattle let alone the ones in Portland. So, why the dramatic difference in power from those two sites? Edit, I think the maximum erp for a C1 at 472 meters is around 30 kw, so it would make sense that they could run about 25 kw from the KGW-TV tower.

 

[fybush]

I'd have to dig more deeply into the history of Anchorage radio to be certain, but I suspect KLEF and some of the others were there long before the C3 class was even created. It may be that they were substandard C (or C1) facilities, and there was never any reason to force a downgrade. It's not like there are any other stations anywhere nearby that would need to force the issue.

I'd also have to look more closely at the Portland move-in (KNRQ?) It's possible one of the apps you're looking at may be for an auxiliary facility. Those are typically lower power if they're at an alternate location, since they're not allowed to exceed the contour distance of the main station.

 

[bobdavcav]

Yes KNRQ. I really don't understand why they're drawing this out so much. Couldn't they have just picked the site on one of the towers and build there? Or do they have to wait for antenna replacement? Even then, you'd think 3 years would be plenty of time to get all the engineering work done.

 

[fybush]

Adding a new signal to a master antenna system, especially a big one like Stonehenge, is a very complicated thing. There's a technical piece to it - you have to rebuild the combiner to work properly with the new addition. There's also a business aspect to it, particularly if there's a plan to rebuild the entire master antenna system going on at the same time. I'm not at all surprised it's taken this long.

 

[bobdavcav]

I guess I'm not either, although I don't know as much about the technical side as you do. What I don't understand is why they didn't either reapply for the same CP as before when they knew the deadline was coming up, or do what they did in January and apply for the Stonehenge site and then kept it there. I guess I could see the schedule on the master antenna replacement being a factor, they could have planned for a replacement long before KNRQ moved. I'm not sure why they didn't keep it there though, since the master antenna at Stonehenge is supposed to be replaced this summer.