Friday, August 13, 2010
Mediumwave Oddities - Transmitter Power
We've talked about geographical mediumwave oddities for the United States, let's shift the discussion to transmitter power. Again, we will use data from current FCC records, this time from August 7, 2010. There are 4784 licensed stations in this survey. I have found 4787 licensed stations in the database, one more than the 4786 total the FCC publishes. I am excluding WR2XJR-670, Portsmouth, Virginia, a questionable FCC record for a synchronous station, and WWWS-1400 and WWGP-1050, both of which are reported licensed and on the air, but have no current antenna engineering record in the FCC database.
Daytime and nighttime data differ, so I will try to be explicit on the figures presented.
THE BIG BOYS
As you probably already know, 50,000 watts (50KW) is the maximum power allowed for a US mediumwave station. All 50KW stations used to be Class A clear channel stations, but that is no longer the case. 50KW stations can be Class A, Class B, or Class D, depending on the area they serve.
First of all, how many total stations are on the air during daytime hours?
All 4784 FCC-licensed stations can operate during daytime hours.
How many 50KW stations are there?
Throughout the FCC dragnet, there are 245 stations transmitting at 50,000 watts during daytime hours. 324 stations are transmitting at 20,000 watts or higher. 600 stations at 10,000 watts or higher. The vast majority, 4184 stations, transmit at a power under 10,000 watts.
Here's some figures for other power levels:
10,000 watters - 331
5,000 watters - 1172
1,000 watters - 1819
500 watters - 271
717 stations transmit with a power less than 1,000 watts during daytime hours.
Which station transmits with the lowest daytime power?
Lowly WBCP-1580, Urbana, Illinois with 135 watts. Only 10 stations total transmit with less than 200 watts.
What is the total power output of all stations combined?
A whopping 27,323,022 daytime watts! (27,323.022 kilowatts)
Currently, power companies in the US charge anywhere from about 8 cents per kilowatt hour to about 20 (Hawaii has the highest rate at 27 cents).
Considering 15 cents per kilowatt hour an average rate, how much does it cost to run all of these transmitters for one hour?
27,323.022 kilowatts per hour costs $4,098 each hour to operate. Over a 12 hour daytime period, the grand total paid to the power companies is an astounding $49,181, essentially 50 thousand dollars per half day in power costs alone.
How many total stations are on the air during nighttime hours?
4178 stations can operate during nighttime hours, out of 4784 stations total. This leaves 606 stations which are licensed for daytime only operations.
How many 50,000 watt stations are authorized to transmit at this power level at night?
97 stations are at the 50KW level during nighttime hours, versus 245 during the daytime. 122 stations are transmitting at 20,000 watts or higher (versus 324). 212 stations at 10,000 watts or higher (versus 600). 3966 stations transmit at a power under 10,000 watts.
Here are the other figures for nighttime hours:
10,000 watters - 78 (versus 331)
5,000 watters - 408 (versus 1172)
1,000 watters - 1360 (versus 1819)
500 watters - 250 (versus 271)
2031 stations transmit with a power less than 1,000 watts during nighttime hours.
Under 1,000 watts, things start to get really interesting, as nighttime operations are a totally different ballgame than daytime due to greatly enhanced signal propagation. Many, many low powered stations abound.
Which station transmits with the lowest nighttime power?
We have a tie. 14 stations transmit with a flea-power signal of only one watt! In fact, 120 stations are on the air transmitting with less than 10 watts! Between 1 and 99 watts, there is at least one station transmitting at each unit of power level, i.e., at 1,2,3,4,5,6,7,8,9,10,11,12,13....47,48,49....all the way to 99 watts.
There are 1028 stations transmitting less than 100 watts at night. Of those, 908 are at power levels between 10 and 99 watts. Between 100 and 500 watts, we have 551 stations.
So, the record holders at 1 watt output level are these 14 stations:
WNBL-1540, Booneville, IN
WRFM-990, Muncie, IN
WGAB-1180, Newburgh, IN
KBOA-1540, Kennett, MO
WZRK-1550, Lake Geneva, WI
WJJT-1540, Jellico, TN
KLKC-1540, Parsons, KS
WSRY-1550, Elkton, MD
WSQR-1180, Sycamore, IL
WCKB-780, Dunn, NC
WPGR-1510, Monroeville, PA
WHFB-1060, Benton Harbor, MI
Of these, Indiana is the clear winner with 3 of the lowest powered stations in the US.
What is the total power output of all nighttime stations combined?
10,856,121 nighttime watts (10,856.121 kilowatts). This is opposed to the daytime total wattage output of 27,323,022 watts. The nighttime power level is about 40% of the daytime level. One hour of nighttime electricity costs the radio stations $1,628. Twelve hours of operation at night costs $19,541.
So, the total cost of mediumwave broadcast transmitter power in the US, operating 24 hours per day, comes to approximately $68,722, based on a 15 cents per kilowatt hour charge by the power companies!
How many of you mediumwave DXers have heard these flea power stations, under 10 watts? Maybe we should have a certificate award for receiving a prescribed number of flea powered stations, perhaps under 100 watts, or even under 10 watts?
Coming up next: Mediumwave Oddities - Towers
More power to you, mediumwave DXer!