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Sunday, December 16, 2018

Late 2018 IBOC Report, KNX-1070, KSL-1160

We talked at some length a few years ago about IBOC, or so-called HD radio. At the time, iBiquity Digital Corporation was the sole licensed vendor for the U.S. That has changed.

A NEW OWNER

Old news by now, in October, 2015, Dedicated To Sound, Inc. (a.k.a. DTS) purchased the rights to this HD Radio technology from iBiquity and is now the new sole owner.


DTS announced thusly:

"DTS is excited to announce it has entered into a definitive agreement to acquire iBiquity Digital Corporation, the developer of digital HD Radio technology for AM/FM audio and data broadcasting for approximately $172 million. DTS expects to finance the transaction through a combination of cash on hand and debt."

iBiquity was the exclusive developer and licensor of HD Radio technology, the sole FCC-approved method for upgrading AM/FM broadcasting from analog to digital. iBiquity’s partners included leading automakers, consumer electronics and broadcast equipment manufacturers, radio broadcasters, semiconductor and electronic component manufacturers and retailers.

The market that has shown some success is the automobile HD Radio market. The home market has not. Said DTS, "This transaction extends our strategy of delivering a personalized, immersive and compelling experience across the network-connected entertainment value chain, and complements our existing suite of technology and content delivery solutions while enabling us to strengthen our position in the large automotive OEM market. Consumers have come to expect a higher quality sound experience in their car, and we believe there is a tremendous opportunity for DTS to capitalize on the upgrade to HD Radio technology as cars are increasingly equipped with screens and advanced entertainment systems.”

iBiquity had successfully driven penetration of HD Radio technology in the North American automotive OEM market. HD Radio technology was built into approximately 35% of cars sold in the U.S. in 2014, and DTS expects the majority of North American vehicles to come equipped with HD Radio technology over time.


ANALYZING IBOC

The IBOC acronym stands for "In Band On Channel". Currently in the U.S., a hybridized version of the digital signal is imposed on the analog signal and the result transmitted. This is supposed to be an interim or transitional method. Stations that are licensed through the FCC for the digital add-on and have entered into contract with iBiquity and now DTS may transmit the hybrid signal. Current FCC records show a total of 237 stations are authorized to transmit IBOC hybridized digital. Many of those who made the initial licensing effort to get a digital signal on the air have terminated transmission due to resultant nighttime skywave interference problems on the broadcast band.

The misnomer here, at least for the hybridized version, is the term "On Channel". The 15 KHz digital sidebands either side of the main carrier bleed fully beyond the adjacent AM channel center and into the adjacent station's far sideband. Let me state this is another way: They have positioned the digital sideband information on the adjacent channel! No filter, on any receiver, regardless of bandwidth, can reject it. However, testing has shown some receiver's passbands are better than others. In order to provide room for these expanded sidebands superimposing digital information on top of analog audio, stations also have had to narrow their audio response to an absolute 5 KHz maximum, further reducing standard analog audio quality. Adherence to strict technical standards is now an absolute imperative, both in the transmitter, modulation technique, and antenna or you have an even worse interference problem. And we all know radio stations often fail in this area of strict adherence. This, currently, is what the FCC calls "Hybrid" digital operation, the precursor to going fully digital at some future date.

OBSERVED SKYWAVE RECEPTION PROBLEMS IN THE WESTERN U.S.

On the AM broadcast band, where this will all end up is anybody's guess. Will it ever go entirely digital? I suspect not, at least for the foreseeable future. The number of facilities registered to transmit hybridized IBOC digital has remained fairly stable over the last couple of years. In 2009 as IBOC was ramping up, 289 facilities were registered with the FCC. That number reached 293 a year later in 2010. Since the peaks of the initial few years, however, the overall decline has been sure but steady.

TopazDesigns runs a nice U.S. AM and Canadian AM station search site. Within it is also a page kept current with the latest IBOC stations on the air. Their current count as of this date shows only 117 transmitting, and only 35 at night. As is evident, interest has waned for digital on the mediumwave band.

Here in the far American West, there are some big boys still transmitting IBOC. Notably, the strongest received in southwestern Arizona at night is Salt Lake City's 50 KW KSL-1160, followed by Los Angeles's 50 KW KNX-1070.

Adjacent to KNX-1070 on its upper side is 50 KW KRLD-1080 in Dallas, Texas. A two tower array with 4.8 dB gain in my direction pushes a respectable 150 KW effective radiated power (ERP) at me. KRLD-1080 is essentially impossible to hear when KNX-1070 is faded up to full strength as digital hash blankets 1080 KHz. Careful nulling of the radio's loopstick does help, but the two stations are nearly 180 degrees opposed to each other.

I mentioned that some radios are better than others in reducing adjacent-channel hash, not withstanding the nulling technique. In my stable of super portables, the Sangean ATS-909X does the best job, followed by the Tecsun PL-880 and the C.Crane EP Radio Pro. The difference in the Sangean is fairly remarkable, I believe owing to the Silicon Labs Si4734/35 DSP chip being used down-chain in the I.F., and the outstanding fidelity of the audio section.

The worst IBOC offender here is Utah's KSL-1160 at 506 miles distant. I am in its sweet spot, propagation-wise. Its 455 ft., half wavelength (+) single tower with gain of 2.31 dB pumps about 85 KW ERP at my direction. KNX-1070 has an almost identical tower, however at only 237 miles distant I am in its skip zone and thankfully much of its signal is wasted overhead in the E-layer on its way to New Mexico and beyond.

My best chance at reception on 1170 KHz, adjacent to KSL-1160 is Tulsa, Oklahoma's 50 KW KFAQ-1170. But it's a long way off at 1057 miles and it takes some tremendous power to overcome KSL's signal. As luck would have it, the three tower array's main lobe is pointed directly at me in western Arizona. With respectable 5.56 dB gain, it pushes an astounding 179 KW ERP at me. KFAQ-1170 should boom in here at night, but caught in KSL-1160's digital hash on 1170 KHz, it barely makes a dent unless KSL is in deep fade. If KFAQ fades up as KSL fades down it makes an appearance. WBAP-820, a 50 KW station also in Dallas and clear of an IBOC hash problem, is in regularly. So is 50 KW WOAI-1200 in San Antonio.

Shown in the graphic is KSL's received signal in my SDRPlay RSP1a SDR receiver's waterfall. As you can see, the sidebands creep well into the adjacent channels 1150 and 1170 KHz. My guess is they are pushing the 5 KHz audio bandwidth, causing needless and excessive digital hash, that, or over-compressing the audio, or both.

We will see in the future where digital will go in the U.S. mediumwave band.

Click image for larger version.

KSL-1160 Salt Lake City, Utah


Wednesday, November 7, 2018

US Ground Conductivity Map v2 2018

It came to my attention some time ago that the map sets are not working correctly. It turned out it was a Google Maps problem. Non-casual Google Map creators are now required to register and obtain a pass key to allow map use. I have done that.

The first change and correction is to the US Ground Conductivity Map. The download link is at the upper right. The new version is v2, 2018.

The US and Canadian Pattern Reference Maps (current 2016 version) are effected as well. They will be updated soon.

Bill

Friday, October 12, 2018

Mediumwave Web Tricks

I use a number of tricks to quickly locate information on mediumwave stations. You might call them shortcuts, or easy ways to get to certain station web site data we might be interested in - and without having to re-navigate each site again looking for what we want. Why not just go directly there? Follow along and I'll show you how.

Here's some one-click examples of what we can get, simply by copying and pasting a link into your browser:

     1. Station broadcast format. Data provided by Arbitron.
     2. General station data. Data provided by fcc.gov
     3. Station's application list. Data provided by fcc.gov
     4. Station's contour map. Data provided by fcc.gov
     5. General station profile information. Data provided by fcc.gov
     6. General station data. Data provided by radio-locator.com
     7. Contour maps. Data provided by radio-locator.com
     8. Satellite .JPG image of transmitter site. Data provided by google.com

Let's go through them, one by one.

1. Get Station Broadcast Format From Arbitron

US and Canadian mediumwave stations file station information, including format, web stream location and other details with Arbitron quarterly. You just have to know where it is.

Here's the link for KLAA for summer 2018. Change the call sign to one of your liking and copy and paste the URL in your browser. We will do this throughout this post.

https://www1.arbitron.com/sip/displaySip.do?surveyID=SU18&band=am&callLetter=KLAA

Substitute call letters of your choice, including Canadian stations. For the surveyID= field, use the current season we are in. i.e., use WI18 for winter 2018, SP18 for spring 2018, SU18 for summer 2018, FA18 for fall 2018. Next year, in 2019, use "19".

Only one season will work, the current season. You can't get historical data. Note, however, that in nearly all cases, Arbitron will show that the station's data is not current for the current season. They are drawing the data off of the previous season's submission. It is indeed current, as the station has not submitted changes.


2. Get General Station Data From The FCC

Here's the link, again for KLAA.

https://transition.fcc.gov/fcc-bin/amq?list=0&call=KLAA

Substitute call letters of your choice, including Canadian, Mexican, or any foreign station that has filed with the FCC.



3. Get A Station's Application List From The FCC

http://licensing.fcc.gov/cgi-bin/ws.exe/prod/cdbs/pubacc/prod/app_list.pl?Callsign=KLAA

Again, for KLAA. Substitute call letters of your choice, including Canadian, Mexican, or any foreign station that has filed with the FCC.



4. Get Public Profile For Station From The FCC

https://publicfiles.fcc.gov/am-profile/KBMB

Substitute call letters of your choice. It appears to be U.S. stations only. Station KBMB used here.



5. Get Daytime Contour Map For A Station From The FCC

https://publicfiles.fcc.gov/am-profile/KBMB/contour-maps/

Substitute call letters of your choice. It appears to be U.S. stations only. Station KBMB used here.



6. Get General Station Data From Radio-Locator

https://radio-locator.com/cgi-bin/finder?freq_exact=Yes&format=&owner_search=starts&count=1&is_lic=Y&is_cp=Y&is_unl=Y&is_ful=Y&is_lp=Y&sort=Call&sr=1&band=AM&call=KLAA&freq=830

Substitute call letters of your choice, including Canadian. Here we must also enter the frequency in KHz. KLAA, 830 example used.



7. Get Contour Map For A Station From Radio-Locator

Here's the link for the daytime contour map for KLAA. Change to h=D.

https://radio-locator.com/cgi-bin/pat?call=KLAA&service=AM&h=D

Substitute call letters of your choice, including Canadian. Use the letter "D" at the end.

Here's the link for the nighttime contour map for KLAA. Change to h=N.

https://radio-locator.com/cgi-bin/pat?call=KLAA&service=AM&h=N

Substitute call letters of your choice, including Canadian. Use the letter "N" at the end.

Some stations are in the Unlimited category, like KOA-850 in Denver, for example. Here's the link for the unlimited contour map for KOA. Change to h=U.

https://radio-locator.com/cgi-bin/pat?call=KOA&service=AM&h=U

Substitute call letters of your choice, including Canadian. Use the letter "U" at the end.



8. Get A Satellite .JPG Image Of A Station's Transmitter Site

Google maps has a function that will create a small .JPG image for you of the satellite ground view of a latitude-longitude coordinate.

This one is a little more difficult. You must know the latitude and longitude of the station transmitter site, but you can get that from the FCC General Station Data link (section #2) above. Replace the latitude (33.92861111) and longitude (-117.61583333) with one of your choice. Remember to use a negative longitude if you are in the western hemisphere, and a negative latitude if you are in the southern hemisphere.

Maximum zoom is 17. Lower the zoom if you need to.

The maptype= parameter can be "hybrid" (terrain with some satellite ground annotation), "satellite", "roadmap" (a road map), or "terrain".

.JPG size is either 640x640 or 320x320. Using scale=2 will double the size. format= can be jpg, png, or gif.

Here's the link for KNMX-540, Las Vegas, New Mexico:

http://maps.google.com/maps/api/staticmap?center=35.57361111,-105.17138889&zoom=17&size=640x640&maptype=hybrid&scale=2&sensor=false&format=jpg

KNMX-540 Static Map from Google

One more handy bit of code to get V-Soft signal data.

Easy Way To V-Soft Signal Data

Now let's write a little HTML to get some V-Soft data.

Get a nice signal strength chart by zip code or station call sign from V-Soft. If you've ever wanted to know what the mediumwave signal strengths are in your zip code from various stations nearby, you can.

Copy the following code into any text editor (like Notepad), and save it as an .HTML file. No changes are necessary.

<html><head></head><body>
GET V-SOFT DATA FOR ZIP CODE OR CALL SIGN:
<form action="http://zipsignal.v-soft.com" id="findzips" method="post" name="findzips">
<input id="zip" name="zip" size="20" type="text" value="123456" /><input type="Submit" /> ZIP CODE</form>
<form action="http://zipsignal.v-soft.com" id="findstations" method="post" name="findstations">
<input id="call" name="call" size="20" type="text" value="KLAA" /><input type="Submit" /> CALL SIGN</form>
</body></html>

Then click the file. Enter either your zip code (or any zip code), or a station's call letters. Click the Submit button. You will be re-directed to the v-soft.com site and see a nice table of signal strengths.

Hope you enjoy these web tricks.

Monday, September 10, 2018

Radio Calculator Program v1.0015

In the process of developing the Radio Data MW program (the program that creates those neat HTML mediumwave pattern maps available at the upper right), I needed some way to convert values back and forth to check accuracy of calculations. Conversions like watts to dBw, mV/m to dBu, microvolts to dBm, etc. I came up with a little calculator "app" that satisfied the need, and called it Radio Calculator. I present it here for your download and use.

Questions about how dB relates to ratio of values (both watts and voltage), passive loop antenna output, wavelength, radio horizon, field strength, and even sine and cosine tables are all covered in a simple to use format.

The program is written in the old standby Visual Basic. It's been tested on Windows 7 through Windows 10.

Install is simple. Download the file from the link at the upper right of this page, unzip, and run the RadioCalculator.exe file. The file is small at 22 KB. There are no special requirements.

I hope you enjoy it and can make use of it.

Some screenshots:

Decibels and Ratio Conversions

Field Strength Conversions

Voltage and Power Conversions

Passive Loop and Antenna Factor Calculations

Wavelength Information

Various Tables, Including Sine and Cosine

Friday, September 7, 2018

Early Fall Conditions Improve

KMON-560 Great Falls, Montana Logged

Logged KMON-560 (5 KW) Great Falls, MT overnight at 01:00 AM local, 08:00 GMT. Also dancing around in there was KSFO-560 (5 KW), San Francisco, CA. I'm in the pattern null of both of these. Although KSFO is fairly routine, I'm surprised at hearing KMON. They're only delivering about 67 watts to me in that notch. Maybe on day power? Will try again tonight. Really hoping to hear Beaumont, TX KLVI-560 (5 KW) one of these days. I'm just a little off the main western lobe. Denver's KLZ-560 usually dominates all.

Japan JOUB-774 Makes The Trip This Morning

Japan JOUB-774 was in there at the local 06:00 hour, 13:00 GMT. Weak audio and time pips at the top of the hour. Just before sunrise in SW Arizona.

Heard on my new Sangean ATS-909X barefoot. I find the sensitivity on the Sangean to be excellent as opposed to some of the reviews. The AGC is a bit overly sensitive, but if you ride the RF gain down a bit it settles down. Old tech, the Sangean, I know, but I'm a happy late purchaser. Superb audio too.

Monday, July 9, 2018

The Good Old Days Of Mediumwave DXing

The blog has been lying low for quite awhile. Time allowing, I'd like to present some new ideas.

I occasionally hear talk of the "good old days" of mediumwave DXing, usually referring to back in the 1960s and earlier. The talk is of nightly cross-country DX, of hearing Los Angeles on the east coast, of foreign stations as a regular occurrence. Usually it gets around to a discussion of how fewer stations were on the mediumwave band in those days. I always wondered what a comparison would look like.

Recently, I came across a 1941 Stephenson's Radio Bulletin on a great site called American Radio History:

https://www.americanradiohistory.com/index.htm

They have scanned many articles and magazines from all eras of radio history, back to the 1920s.

I decided to tabulate the 1941 list of mediumwave stations against today's 2108 list and see what it looks like. This has been a project idea I've been thinking about for a long time. I just haven't been able to get a station list with the data readably usable, so I decided to write some code to extract it.

Presented below is the mediumwave radio world of 1941 compared to today's 2018. The 2018 US station counts are all nighttime stations only, at current nighttime power levels. The 1941 station data includes all stations from that year (tabulated in January, 1941). Less than 10% are restricted in their nighttime use of power , a few are daytimers only. That just means there would be even less interference than what can be extrapolated from the table.

So, were these the good old days? I would say so. In 1941 we only had about 31% of the RF wattage flying around at night. There were a total of 833 stations transmitting at night, as opposed to the approximately 4058 transmitting at night tonight. What the table doesn't show is that the stations transmitting at night in 1941 generally transmitted at a higher power than those of today, Fewer stations at higher powers = better DX.

 -----1941-2018 DIFFERENCES ON THE MEDIUM WAVES-----

 530  (2018) #Stations =   0    TotalWatts =       0
      (1941) #Stations =   0    TotalWatts =       0

 540  (2018) #Stations =  20    TotalWatts =  49,620
      (1941) #Stations =   0    TotalWatts =       0

 550  (2018) #Stations =  24    TotalWatts =  77,923
      (1941) #Stations =   9    TotalWatts =  33,000

 560  (2018) #Stations =  23    TotalWatts =  60,320
      (1941) #Stations =   9    TotalWatts =  33,000

 570  (2018) #Stations =  19    TotalWatts =  53,379
      (1941) #Stations =   9    TotalWatts =  24,250

 580  (2018) #Stations =  24    TotalWatts =  97,298
      (1941) #Stations =   7    TotalWatts =  31,000

 590  (2018) #Stations =  27    TotalWatts =  61,390
      (1941) #Stations =   5    TotalWatts =  17,000

 600  (2018) #Stations =  23    TotalWatts =  55,021
      (1941) #Stations =   5    TotalWatts =  17,000

 610  (2018) #Stations =  27    TotalWatts =  67,795
      (1941) #Stations =   7    TotalWatts =  26,500

 620  (2018) #Stations =  23    TotalWatts =  68,577
      (1941) #Stations =  11    TotalWatts =  38,250

 630  (2018) #Stations =  25    TotalWatts =  55,374
      (1941) #Stations =   6    TotalWatts =  17,200

 640  (2018) #Stations =  15    TotalWatts =  71,660
      (1941) #Stations =   3    TotalWatts =  55,500

 650  (2018) #Stations =   8    TotalWatts = 113,420
      (1941) #Stations =   1    TotalWatts =  50,000

 660  (2018) #Stations =  12    TotalWatts = 125,179
      (1941) #Stations =   2    TotalWatts =  50,500

 670  (2018) #Stations =   9    TotalWatts = 121,003
      (1941) #Stations =   1    TotalWatts =  50,000

 680  (2018) #Stations =  20    TotalWatts = 226,216
      (1941) #Stations =   3    TotalWatts = 102,500

 690  (2018) #Stations =  19    TotalWatts =  53,274
      (1941) #Stations =   0    TotalWatts =       0

 700  (2018) #Stations =   8    TotalWatts =  73,690
      (1941) #Stations =   1    TotalWatts =  50,000

 710  (2018) #Stations =  15    TotalWatts = 201,560
      (1941) #Stations =   3    TotalWatts =  65,000

 720  (2018) #Stations =   6    TotalWatts = 111,286
      (1941) #Stations =   1    TotalWatts =  50,000

 730  (2018) #Stations =  29    TotalWatts =   4,714
      (1941) #Stations =   0    TotalWatts =       0

 740  (2018) #Stations =  28    TotalWatts = 196,021
      (1941) #Stations =   4    TotalWatts =  52,250

 750  (2018) #Stations =   8    TotalWatts = 139,630
      (1941) #Stations =   2    TotalWatts =  52,500

 760  (2018) #Stations =  11    TotalWatts = 119,771
      (1941) #Stations =   4    TotalWatts =  57,000

 770  (2018) #Stations =  10    TotalWatts = 122,180
      (1941) #Stations =   2    TotalWatts =  60,000

 780  (2018) #Stations =   8    TotalWatts = 115,049
      (1941) #Stations =   9    TotalWatts =  29,750

 790  (2018) #Stations =  41    TotalWatts =  60,498
      (1941) #Stations =   3    TotalWatts =  58,500

 800  (2018) #Stations =  29    TotalWatts =  16,513
      (1941) #Stations =   2    TotalWatts = 100,000

 810  (2018) #Stations =  16    TotalWatts = 207,678
      (1941) #Stations =   2    TotalWatts =  51,000

 820  (2018) #Stations =  12    TotalWatts =  73,335
      (1941) #Stations =   1    TotalWatts =  50,000

 830  (2018) #Stations =  11    TotalWatts = 154,750
      (1941) #Stations =   4    TotalWatts =  57,000

 840  (2018) #Stations =  10    TotalWatts =  83,105
      (1941) #Stations =   0    TotalWatts =       0

 850  (2018) #Stations =  17    TotalWatts = 229,930
      (1941) #Stations =   4    TotalWatts =  56,250

 860  (2018) #Stations =  27    TotalWatts =  81,799
      (1941) #Stations =   2    TotalWatts =  51,000

 870  (2018) #Stations =   9    TotalWatts =  63,500
      (1941) #Stations =   2    TotalWatts = 100,000

 880  (2018) #Stations =  16    TotalWatts = 132,022
      (1941) #Stations =  12    TotalWatts =  15,250

 890  (2018) #Stations =  11    TotalWatts =  83,810
      (1941) #Stations =   8    TotalWatts =  27,500

 900  (2018) #Stations =  42    TotalWatts =  16,948
      (1941) #Stations =  11    TotalWatts =  30,000

 910  (2018) #Stations =  48    TotalWatts = 103,992
      (1941) #Stations =   0    TotalWatts =       0

 920  (2018) #Stations =  43    TotalWatts =  51,396
      (1941) #Stations =   8    TotalWatts =  19,500

 930  (2018) #Stations =  48    TotalWatts =  61,745
      (1941) #Stations =   5    TotalWatts =  16,500

 940  (2018) #Stations =  31    TotalWatts = 102,952
      (1941) #Stations =   7    TotalWatts =  27,000

 950  (2018) #Stations =  42    TotalWatts = 175,799
      (1941) #Stations =   4    TotalWatts =  15,500

 960  (2018) #Stations =  43    TotalWatts =  65,320
      (1941) #Stations =   0    TotalWatts =       0

 970  (2018) #Stations =  50    TotalWatts =  84,713
      (1941) #Stations =   3    TotalWatts =  11,000

 980  (2018) #Stations =  43    TotalWatts =  77,055
      (1941) #Stations =   1    TotalWatts =  50,000

 990  (2018) #Stations =  37    TotalWatts =  57,793
      (1941) #Stations =   2    TotalWatts =  51,000

1000  (2018) #Stations =   8    TotalWatts = 107,940
      (1941) #Stations =   2    TotalWatts =  51,000

1010  (2018) #Stations =  33    TotalWatts =  97,098
      (1941) #Stations =   5    TotalWatts =  17,000

1020  (2018) #Stations =  11    TotalWatts = 164,600
      (1941) #Stations =   2    TotalWatts =  51,000

1030  (2018) #Stations =  16    TotalWatts = 123,103
      (1941) #Stations =   0    TotalWatts =       0

1040  (2018) #Stations =  10    TotalWatts =  68,113
      (1941) #Stations =   4    TotalWatts = 100,750

1050  (2018) #Stations =  45    TotalWatts =  67,845
      (1941) #Stations =   4    TotalWatts =  61,000

1060  (2018) #Stations =  20    TotalWatts =  70,437
      (1941) #Stations =   3    TotalWatts =  61,000

1070  (2018) #Stations =  21    TotalWatts = 110,877
      (1941) #Stations =   3    TotalWatts =  50,600

1080  (2018) #Stations =  16    TotalWatts = 145,216
      (1941) #Stations =   3    TotalWatts =  60,000

1090  (2018) #Stations =  10    TotalWatts = 157,238
      (1941) #Stations =   1    TotalWatts =  50,000

1100  (2018) #Stations =   8    TotalWatts = 115,240
      (1941) #Stations =   5    TotalWatts =  72,000

1110  (2018) #Stations =  10    TotalWatts = 141,012
      (1941) #Stations =   2    TotalWatts =  55,000

1120  (2018) #Stations =   9    TotalWatts = 103,705
      (1941) #Stations =  13    TotalWatts =  13,350

1130  (2018) #Stations =  18    TotalWatts = 164,484
      (1941) #Stations =   2    TotalWatts =  70,000

1140  (2018) #Stations =  14    TotalWatts = 150,746
      (1941) #Stations =   2    TotalWatts =  30,000

1150  (2018) #Stations =  48    TotalWatts = 113,462
      (1941) #Stations =   1    TotalWatts =  50,000

1160  (2018) #Stations =  25    TotalWatts = 126,221
      (1941) #Stations =   2    TotalWatts =  15,000

1170  (2018) #Stations =  13    TotalWatts = 139,368
      (1941) #Stations =   1    TotalWatts =  50,000

1180  (2018) #Stations =  14    TotalWatts =  80,935
      (1941) #Stations =   3    TotalWatts =  56,000

1190  (2018) #Stations =  20    TotalWatts = 103,867
      (1941) #Stations =   1    TotalWatts =  50,000

1200  (2018) #Stations =  14    TotalWatts = 148,070
      (1941) #Stations =  72    TotalWatts =  16,350

1210  (2018) #Stations =  19    TotalWatts =  98,977
      (1941) #Stations =  68    TotalWatts =  14,750

1220  (2018) #Stations =  43    TotalWatts =  55,519
      (1941) #Stations =  10    TotalWatts =  28,250

1230  (2018) #Stations = 164    TotalWatts = 156,357
      (1941) #Stations =   7    TotalWatts =  23,000

1240  (2018) #Stations = 154    TotalWatts = 148,812
      (1941) #Stations =   5    TotalWatts =  11,750

1250  (2018) #Stations =  52    TotalWatts =  65,657
      (1941) #Stations =   9    TotalWatts =  21,000

1260  (2018) #Stations =  51    TotalWatts =  90,041
      (1941) #Stations =  10    TotalWatts =  25,250

1270  (2018) #Stations =  53    TotalWatts = 114,009
      (1941) #Stations =   9    TotalWatts =  17,700

1280  (2018) #Stations =  52    TotalWatts =  53,333
      (1941) #Stations =   8    TotalWatts =  17,250

1290  (2018) #Stations =  48    TotalWatts =  83,100
      (1941) #Stations =   9    TotalWatts =  25,700

1300  (2018) #Stations =  59    TotalWatts = 130,076
      (1941) #Stations =   9    TotalWatts =  21,000

1310  (2018) #Stations =  55    TotalWatts =  66,965
      (1941) #Stations =  69    TotalWatts =  15,550

1320  (2018) #Stations =  56    TotalWatts =  72,802
      (1941) #Stations =   6    TotalWatts =  21,500

1330  (2018) #Stations =  53    TotalWatts =  84,399
      (1941) #Stations =   8    TotalWatts =  23,500

1340  (2018) #Stations = 163    TotalWatts = 154,407
      (1941) #Stations =   9    TotalWatts =  16,250

1350  (2018) #Stations =  56    TotalWatts =  48,789
      (1941) #Stations =   6    TotalWatts =  19,000

1360  (2018) #Stations =  58    TotalWatts =  58,040
      (1941) #Stations =   8    TotalWatts =  10,750

1370  (2018) #Stations =  53    TotalWatts =  87,796
      (1941) #Stations =  81    TotalWatts =  18,350

1380  (2018) #Stations =  58    TotalWatts = 129,410
      (1941) #Stations =   5    TotalWatts =   9,000

1390  (2018) #Stations =  54    TotalWatts =  78,856
      (1941) #Stations =   6    TotalWatts =  18,000

1400  (2018) #Stations = 175    TotalWatts = 170,415
      (1941) #Stations =   6    TotalWatts =  16,500

1410  (2018) #Stations =  56    TotalWatts =  53,636
      (1941) #Stations =   8    TotalWatts =   9,500

1420  (2018) #Stations =  61    TotalWatts =  53,262
      (1941) #Stations =  61    TotalWatts =  13,450

1430  (2018) #Stations =  57    TotalWatts =  97,857
      (1941) #Stations =   8    TotalWatts =  20,000

1440  (2018) #Stations =  56    TotalWatts =  44,551
      (1941) #Stations =   7    TotalWatts =  13,500

1450  (2018) #Stations = 175    TotalWatts = 167,406
      (1941) #Stations =   7    TotalWatts =  15,000

1460  (2018) #Stations =  65    TotalWatts =  77,316
      (1941) #Stations =   2    TotalWatts = 100,000

1470  (2018) #Stations =  47    TotalWatts =  62,378
      (1941) #Stations =   3    TotalWatts =  15,000

1480  (2018) #Stations =  63    TotalWatts =  72,040
      (1941) #Stations =   3    TotalWatts =  15,000

1490  (2018) #Stations = 182    TotalWatts = 174,560
      (1941) #Stations =   2    TotalWatts =  60,000

1500  (2018) #Stations =  13    TotalWatts = 121,038
      (1941) #Stations =  62    TotalWatts =  14,450

1510  (2018) #Stations =  12    TotalWatts = 144,770
      (1941) #Stations =   0    TotalWatts =       0

1520  (2018) #Stations =  18    TotalWatts = 196,492
      (1941) #Stations =   0    TotalWatts =       0

1530  (2018) #Stations =  11    TotalWatts = 110,763
      (1941) #Stations =   3    TotalWatts =   3,000

1540  (2018) #Stations =  23    TotalWatts = 149,357
      (1941) #Stations =   0    TotalWatts =       0

1550  (2018) #Stations =  50    TotalWatts =  41,851
      (1941) #Stations =   2    TotalWatts =   6,000

1560  (2018) #Stations =  19    TotalWatts =  90,638
      (1941) #Stations =   0    TotalWatts =       0

1570  (2018) #Stations =  55    TotalWatts =  28,476
      (1941) #Stations =   0    TotalWatts =       0

1580  (2018) #Stations =  43    TotalWatts = 109,951
      (1941) #Stations =   0    TotalWatts =       0

1590  (2018) #Stations =  59    TotalWatts =  63,336
      (1941) #Stations =   0    TotalWatts =       0

1600  (2018) #Stations =  58    TotalWatts =  96,127
      (1941) #Stations =   0    TotalWatts =       0

Total watts 2018 = 10,829,145
Total watts 1941 =  3,389,200

If you want a good example of present-day nighttime confusion, one only has to look at a single channel, perhaps one of the worst. 1490 KHz, one of our US graveyard channels has 182 stations transmitting all at once. The results are shown below. Reception contours are set to the 0.1 mV/m level, a level which should generate signal in even the most marginal receiver, within range.

Good days must be ahead.

The Graveyard (and only part of it). 1490 KHZ