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Wednesday, May 23, 2012

RADIO-TIMETRAVELLER Maps #2

50 Kilowatts Night - U.S.

50 Kilowatts Night - U.S.

Our next map depicts all 50 kilowatt stations broadcasting during nighttime hours in the United States. 98 stations are represented. Black flags indicate allocations in the nighttime service class, pink flags the unlimited service class (24-7). The FCC defines service classes as DAYTIME, NIGHTTIME, UNLIMITED, and CRITICAL HOURS (the first two hours of daylight after sunrise and the last two hours of daylight before sunset). Data is from the 4-24-12 FCC database.

Representative antenna pattern plots are also shown.

Here are the statistics.

59 stations are Class A. 39 are Class B. 0 are Class C. 0 are Class D.

50 are located east of St. Louis, 48 are west of St. Louis.

51 are "W" callsigns. 47 are "K" callsigns.

The 98 stations broadcast using 269 towers.

30 stations broadcast an omni-directional pattern (single tower). 68 broadcast a directional pattern (multi-tower).

1 station is on the FCC "Silent" list: WDCD-1540.

If we divide the western hemisphere MW broadcast band in half (the center is at 1115 KHz), we have an equal number of MW channels below 1115 KHz and above 1115 KHz. There are 31 nighttime 50KW stations broadcasting above 1115 KHz. 67 broadcast below 1115 KHz.

Monday, May 21, 2012

Mediumwave DX Meets The Tablet Computer

A previous series on this blog talked about the wealth of information we mediumwave DXers have for listing stations, and ways to reference it in the field. Last year about this time I bought an eReader (a Nook Color), with the idea of using it to read books and other saved documents. What I discovered was how easy it was to create customized station lists from various web sources using my laptop, then transfer them to the eReader for reference in the field when DXing. The second part in that series talked about using the eReader for displaying DX lists.

After a summer's use it became apparent that a tablet computer might be an even more usable device, as it would allow better web access, more options for file reader software, and a bigger screen (10 inch vs. 7 inch). This spring I purchased an Asus Transformer TF101 Android tablet. It has been a good choice.

As mentioned previously, typical station lists can be created in several forms using various web or other sources. Reader apps for tablet computers can handle .TXT (text) file format, .PDF (Adobe's Personal Document File) format, .HTML (web) format, and others - even .XLS (XCEL) spreadsheet files or comma-separated value text (.CSV) files.

Three favorite web sites of mine for mining mediumwave AM data are Lee Freshwater's AM Logbook, MWList, and the FCC's AM Query. Let's review what they have to offer.

AM Logbook will generate a single web page list of stations by frequency, callsign, state, city, transmitter location, and others. US and Canadian stations are represented. The page can be saved locally by your browser and transferred to your tablet through either a hard connection, WiFi, or a Cloud service like Dropbox or Box. AM Logbook also supplies its AM list in downloadable XCEL spreadsheet form.

MWList, a more complicated site, attempts to document all AM stations worldwide, by country. It encourages users to register, but its data is also available to non-registered users. MWList has the ability to create a customized country file in PDF form which is then made available for your download. This is really the way to go on this site. Enter the site, login if you are a member or click "Continue as guest", then click the "Downloads" heading tab. Check off the countries desired, then download your PDF file. Transfer to your tablet as indicated above.

MWList also outputs country data to a generated web page, like AM Logbook. Country data is initially displayed by frequency, but the data columns on the page can be click-sorted by location, callsign, state, etc. Data is presented in an HTML "frame" within a parent page, so saving the web page core data in this way is not as easily done. Sometimes it is necessary to break the frame out into its own window, and this is the technique that I use. Some browsers allow this option and present a right-click menu item to accomplish it. Firefox and Opera include this function. Once the frame is broken out into its own page it is easily saved as HTML. Text formatting is maintained this way.

Data from both AM Logbook and MWList are based on a variety of sources, one being actual reception reports. Canadian data seems accurate for both, as it is not drawn from the FCC database. Ditto Mexico and other countries for MWList.

The third option, the FCC's AM Query, can also be used to create a station reference file. US data should be highly accurate, but be suspicious of any foreign data. You would be better off with AM Logbook or MWList for Canada and Mexico or other countries. Output can be displayed as a simple web page or a text file, easily transferred to a tablet, as above.

My own Radio Data MW program has the capability of creating station list files in HTML and CSV formats. I often use its files on my tablet, as I can set them up to show expected signal strengths and sunrise/sunset times for each station, something not available with any of the other sources.

Much reader software (in the form of apps) is available for the tablet. Adobe Reader (free) and ezPDF Reader (less than $5) are good ones for displaying PDF format. Your tablet already has text reading software and an HTML browser, though many others are also available for free through the Google Play Store (previously known as Google Marketplace). Apple's iPad has similar software available at their App Store.

An advantage to staying with the HTML format for your AM list is the tablet browser's pinch-to-zoom function. With file sizes fairly large, and long line lengths, it is advantageous to be able to zoom the text smaller and larger. Most PDF readers have the pinch-to-zoom capability, but not all work as well as the web browsers. Basic text (.TXT) reader software doesn't always have an appropriate zoom capability, or may wrap long line lengths causing confusion. HTML is the better choice here.

Tablet batteries typically last 6-10 hours, more than enough for a casual afternoon or night of DXing. All tablets seem to have sound recording capability, and most have video and sound recording, both. Thus your device can also be used to create a record of your DX catch for personal record or verification purposes, an added bonus to owning a tablet.

Turn your tablet device into a mediumwave DXer's station reference!

Viewing a MW database on a tablet

Sunday, May 13, 2012

RADIO-TIMETRAVELLER Maps #1

50 Kilowatts Daytime - U.S.

50 Kilowatts Daytime - U.S.

Something new here on the blog - RADIO-TIMETRAVELLER Maps. On occasion I will present a map of interest to the mediumwave DXer. Maps and charts are generated by the Radio Data MW program. Here is the first one. Data is from the 4-24-12 FCC database.

The map depicts all 50 kilowatt stations broadcasting during daytime hours in the United States. 248 stations are represented. Yellow flags indicate allocations in the daytime service class, pink flags the unlimited service class (24-7). The FCC defines service classes as DAYTIME, NIGHTTIME, UNLIMITED, and CRITICAL HOURS (the first two hours of daylight after sunrise and the last two hours of daylight before sunset).

Representative antenna pattern plots are also shown. As you can see, not all are omni-directional as might be expected for 50KW stations. Obviously due to map size constraints, a number of station flags overlap, as do their patterns. Thus, for example, you see KXEN-1010, St. Louis, MO, highly directional, sits under KMOX-1120's omni-directional pattern.

Now, some statistics.

60 stations are Class A. 157 are Class B. 0 are Class C. 31 are Class D.

134 are located east of St. Louis, 114 are west of St. Louis.

137 are "W" callsigns. 111 are "K" callsigns.

The 248 stations broadcast using 628 towers.

103 stations broadcast an omni-directional pattern (single tower). 145 broadcast a directional pattern (multi-tower).

4 stations are on the FCC "Silent" list: WSJC-810, KYWN-890, WQOM-1060, WDCD-1540.

If we divide the western hemisphere MW broadcast band in half (the center is at 1115 KHz), we have an equal number of MW channels below 1115 KHz and above 1115 KHz. There are 85 daytime 50KW stations broadcasting above 1115 KHz. 163 broadcast below 1115 KHz.

The last graphic is a plot centered on the geographic center of the contiguous U.S., near Lebanon, Kansas. It shows the distribution of 50KW daytime stations radiating out from this location, using a scale of 2000 miles. A vague outline of the continental US can be detected, with 4 satellite 50KW stations towards the northwest (Alaskan stations), and a solitary 50KW station to the southeast in Puerto Rico (WKVM-810).

50 Kilowatts Daytime - U.S.

Hope you enjoy the map and chart. Look for more interesting maps and statistics to come.

Sunday, May 6, 2012

Canadian AM List

Let's continue with our topic of governmental radio station databases and create a customized Canadian AM list for our mediumwave DXing use.

Download Canadian AM List (creation date: 05-06-2012)

A previous article on RADIO-TIMETRAVELLER, Radio Station Databases 101,  discussed several governmental databases that are available online. The Canadian database is one of them. Using the Radio Data MW program, I set out to make a Canadian AM station list right from the official files.


Canada has a nice AM Query of their own, like the FCC's AM Query. But also like the FCC's, the output does not tell the entire story, leaving out detailed technical information. We are in luck, however. It turns out that Canada's AM Query searches a deeper database just like the FCC does, so much of the information is available, though hidden.

The Industry Canada engineering database houses the files we need. Links are shown just below.

Industry Canada engineering page
Industry Canada engineering database (baserad.zip)

Rather than simple text files, Canada has chosen a dBase file format (.DBF) for its files. Download and unzip baserad.zip and you will see the many files that comprise Canadian broadcast - AM, FM, and TV. Though the records are somewhat textual in nature, they are more like XCEL records and a text editor cannot be used to view them. You must use a specialized viewer in order to look inside.

CDBF for Windows by WhiteTown Software is one such viewer, which also offers file conversion utilities. A demo version is available, though it it is only usable for a short time. Other DBF file viewers with conversion abilities are also available, notably the free Exportizer.

What we need to do is convert the DBF file to a readable text file so we can process it. We will use Exportizer to open the Canadian DBF file and convert it to a comma-seperated values (.CSV) file, readable by Radio Data MW with some simple tweaking.

So which file do we use to gather information on Canadian mediumwave stations? From the Industry Canada database files, one file stands out that will give us most of the information we want: callsign, frequency, transmitter latitude and longitude, station class, and daytime and nighttime powers. That would be the AMSTATIO.DBF file.

Comparable to the FCC's facility.dat file, Canada's AMSTATIO.DBF file contains basic station information. But also like the FCC's facility.dat, it contains many stations outside Canada. The current AMSTATIO.DBF file I have (dated 4-20-12) documents some 9503 station facilities from not only Canada, but the United States and Mexico as well. We will have to strip out the unnecessary country data. Easy enough.


Now on to the results. I have created a list of the current, operational Canadian AM stations in .HTML form which will display nicely on your computer. A .CSV type file is also included which may be read into a spreadsheet form. The list contains only licensed stations. Nothing in this list has been verified on the air, though it is official and right from the Canadian governmental files. I have calculated local sunrise/sunset times for all stations for this date (5-6-12).

The Canadian AM broadcast service is comprised of 321 station facilities, transmitting in 641 services (daytime service and nighttime service), with varied station classes of A, B, C, and LP (low power).

34 class A stations, 249 class B stations, 74 class C stations, and 284 low power stations round up the list.

For those curious about output powers, 48 stations broadcast at 50KW during the daytime, 40 during nighttime hours. 8 broadcast between 10,001 watts and 49,999 watts during daytime hours, 10 during nighttime hours. 66 broadcast at the 10KW power level during daytime hours, 53 during nighttime hours. 57 broadcast at power levels between 100 watts and 9,999 watts during daytime hours, 75 during nighttime hours.

Stations broadcasting at power levels below 100 watts are considered low power facilities, and are licensed as such with the special license class of LP. There are 142 of them. CBPC-1 and CBPD-1, both out of Glacier Park, British Columbia, have the lowest power level at 5 watts, day and night.

The following frequencies are devoid of any MW broadcast activity in Canada:

550 KHz
670 KHz
700 KHz
720 KHz
780 KHz
1000 KHz
1020 KHz
1030 KHz
1080 KHz
1120 KHz
1160 KHz
1180 KHz
1300 KHz
1360 KHz
1390 KHz
1500 KHz
1520 KHz
1530 KHz
1590 KHz
1600 KHz
1620 KHz
1640 KHz
1660 KHz
1680 KHz
1700 KHz

Canada has 122 graveyard stations. 61 broadcast during daytime hours, 61 during nighttime hours.

Canada has 6 X-band stations (1610-1700 KHz).

Low power stations (99 watts or less) occur throughout the mediumwave frequency band. The following frequencies are occupied by LP stations exclusively:

650 KHz
750 KHz
830 KHz
970 KHz
1090 KHz
1100 KHz
1110 KHz
1170 KHz
1230 KHz
1340 KHz
1400 KHz
1480 KHz
1560 KHz
1630 KHz

Download Canadian AM List (creation date: 05-06-2012)