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AM's Lowering Power

S

Santa fe

I see Chicago 1000 AM is going to move its towers and lower night power to 38kw. Will that affect its night signal a lot? Would that also impact whatever future Parma 1000 might have?
Remember "Super CFL"?
And I see other am stations going for powers less than 100 watts at night. Why bother? Who can hear that?
 
Santa fe said:
I see Chicago 1000 AM is going to move its towers and lower night power to 38kw. Will that affect its night signal a lot? Would that also impact whatever future Parma 1000 might have?
Remember "Super CFL"?
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It takes four times the power to double coverage, so reducing power by 25% is just a tiny reduction in effective coverage.

The current and new owner of the station bought it without a site, as the land is worth more than the station. This is the best the new owner could do within available shared sites.
Santa fe said:
And I see other am stations going for powers less than 100 watts at night. Why bother? Who can hear that?
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They nearly all have translators on FM and only need to keep the AM on the air enough to justify the translator. They assume nobody will listen to the AM
 
At some point, the FCC is going to need to lower the minimum 250 watt level and allow whip-type capacitive top hat antennas without a waiver. Only the lucky stations find another station to diplex with.
 
1. An AM station may elect to reduce power for reasons of their own choosing.

2. Reduction of minimum power of a given station does not change incoming interference from other stations, power lines and other devices. At greatly reduced power usable local coverage declines precipitously, yet creation of significant outgoing interference can remain. This is not necessarily good allocation practice.

3. In my opinion, unless an AM station had plenty of money and wanted to locate on higher priced land for a reason, historically they located farther out on land that was less expensive, if they were OK with the resulting signal.

It's a bit of an illusion; AM site land that is now "worth more than the station" may have been located outside town when the station was built. No different than the farm that is now high market price land, and is sold for highest and best use. Or not.

4. My view is underlying real estate and the AM license/business are two different things. Land is a hard physical asset, business activities come and go. Might not be good logic to connect them automatically. i.e. reduction of market value of the occupying business does not mean the owner "has" to sell the land. Just because market price is high, does not mean you have to sell today.

Some people may operate a business because they want to, as a hobby activity, covering an operating loss with discretionary income. Some own a boat, high-end car or vacation cottage, others have a radio station, restaurant, boutique shop, drinking establishment, etc.
 
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I'm seeing stations drop below 250 watts days without an issue. In St. Louis, KXEN once was 50,000 watts directional days. Don't recall the night power and directional. Now KXEN is diplexed and 160 watts days and something like 14 watts nights all non-directional. And they have a translator or two.
 
Often, stations will downgrade on purpose in order to save money, sell their valuable transmitter land or to allow a co-owned station on a nearby frequency to upgrade. An example of this is WWBB in Providence (101.5) which was a full class B (50KW). Not far away in Boston, was co-owned 101.7 with limited coverage. It was important to get 101.7 upgraded, so they cut back Providence in order to allow the more valuable Boston station to upgrade. It was a smart move because it allowed the more important market station to upgrade, and it did not impact WWBB in the Providence Nielsen, since the reduced WWBB signal still covered the Providence metro. Evidence of no Providence impact? WWBB is currently the #2 rated station in the Providence book.
 
KilowattKat said:
The time will come when the land, those 'lucky' to be diplexed sites are sitting on, gets sold and there is nowhere else to go.
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Or, as in the case of WLW in Cincinnati, the land around the tower is sold and developed into shopping and other services, while the tower remains looming over it. Might have a ground system issue there, but the tower still has a place to live and it's kind of an attraction. Not the first time development has taken place under an AM tower. And this tower is a beautiful site.
 
kevtronics said:
For example, "Towers Shopping Center" in Roanoke, VA, so named because it doubles as the transmitter site of WFIR, with one tower completely surrounded by the building and another in the parking lot:

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KFI in LA has warehouses on the land. KTNQ and KEIB in LA also do, with an interesting 10 meter above ground counterpoise system. KTAR 1020 in Phoenix has a shopping center around it.

When I wandered around Central America in 1963 visiting stations, the majority of those in Guatemala, El Salvador and Honduras were on the rooftop of buildings, either short verticals or longwires.
 
Reduction of licensed power by an AM station reduces outgoing interference to other stations, and if another station does not use the spectrum, overall interference on the band has been reduced. The benefit is reduced if the channel is crowded.

A station operating on a local channel may "need" five co-channel stations gone in order to significantly reduce incoming interference at night. 1240 has 146 stations in the USA. There are seven 1240 stations in Texas.
 
DavidEduardo said:
KFI in LA has warehouses on the land. KTNQ and KEIB in LA also do, with an interesting 10 meter above ground counterpoise system. KTAR 1020 in Phoenix has a shopping center around it.

When I wandered around Central America in 1963 visiting stations, the majority of those in Guatemala, El Salvador and Honduras were on the rooftop of buildings, either short verticals or longwires.
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And don't forget about the infamous 'Lumberyard 1440' KAZG Scottsdale, AZ with their stand-alone tower in the middle of...you guessed it, a lumberyard.
 
Greg Strickland said:
Reduction of licensed power by an AM station reduces outgoing interference to other stations, and if another station does not use the spectrum, overall interference on the band has been reduced. The benefit is reduced if the channel is crowded. A station operating on a local channel may "need" five co-channel stations gone in order to significantly reduce incoming interference at night. 1240 has 146 stations in the USA.
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Having nothing useful to do, I tabulated as of June 1 the stations on the former Class IV channels of 1230, 1240, 1340, 1400, 1450 and 1490.

1230 150
1240 138
1340 151
1400 156
1450 153
1490 171

That is 919 stations, or of the 4496 AMs as of that date that I tabulated... including CPs. That is almost exactly 20% of all US AM stations on those 6 frequencies.

Imagine if all were granted translators with a permanency guarantee if they vacated the AM band.

Ain't trivia fun? :unsure:
 
KilowattKat said:
And don't forget about the infamous 'Lumberyard 1440' KAZG Scottsdale, AZ with their stand-alone tower in the middle of...you guessed it, a lumberyard.
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Heck, when I got to Ecuador, in Quito there were about 26 AM station on the air. Several had longwire "inverted L" antennas strung between two Eucalyptus trees and using burried car radiators or a whole car chassis as the ground.

At the time, only 4 stations had actual towers.
 
Greg Strickland said:
AM Query just gave me 146 on 1240. I did not have my glasses on, though.
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I'm using a bit dated (June) database and it does not include a couple of stations that were silent, I think.
 
The database may have inadvertent duplicate entries, I did not check it with that detail. In any event that is a lot of background noise coming in at night.
 
Greg Strickland said:
The database may have inadvertent duplicate entries, I did not check it with that detail. In any event that is a lot of background noise coming in at night.
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And with today's wallwarts and friends, their coverage is so limited by noise in most areas that they are near becoming useless.
 
kevtronics said:
For example, "Towers Shopping Center" in Roanoke, VA, so named because it doubles as the transmitter site of WFIR, with one tower completely surrounded by the building and another in the parking lot:

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A long time ago I came across a shopping center where a 3 (or 4) tower array was right in the middle of the parking lot! You could literally park right in front of a tower as if it was a light post. I forgot which station that was, but I think it was located somewhere in the same general area or more towards the north/northeast.
 
Directional Ray said:
Or, as in the case of WLW in Cincinnati, the land around the tower is sold and developed into shopping and other services, while the tower remains looming over it. Might have a ground system issue there, but the tower still has a place to live and it's kind of an attraction. Not the first time development has taken place under an AM tower. And this tower is a beautiful site.
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Prior to the pandemic, the land around the WTAM tower was up for sale. Not sure what happened, but it appears that the sale was eventually canceled or postponed. I doubt that houses or even a shopping center would have been built there. Small offices, maybe.
 
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