For the last few weeks, KSTP AM 1500 has been creating some serious interference from 1400 khz to 1600 khz. It's an issue for all of my tuners, even my ultra selective CC Radio 3. I live about 6 miles from the transmitter and have never experienced this before. So I'm thinking there is some sort of issue with the transmitter. Any ideas?
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KSTP AM Issues
- Thread starter pattywells
- Start date
Contact the station with recorded proof and ask what’s going on.
15 has been on autopilot for about 5 years...perhaps they don't even know.
Unless a new building was just erected within a few hundred yards of KSTP, that's not possible. At least assuming pattywells observation of "the last few weeks" is accurate.
Well that's what the CE's over there told someone who lives within 2 miles of 1500's tower. The FCC did take a look last year. The CE was told that they had to use 5kw Non directional night power (STA) until they could "find" the problem. They blamed it on a new building within the last 6 years or so. I don't believe that for a second either. It did disappear for a while in 2020 or 21 but it was short lived so that tells me its not a building.
Its time multiple people wrote into the FCC
Its time multiple people wrote into the FCC
This is helpful. I really only noticed it a few weeks ago, but I don't spend that much time on that end of the dial. As much as I like the idea of Hubbard interfering with Salem's nonsense on 1440 and 1570, someone should probably do something about it.
My directional AM experience is very limited. I get that a building can put a null or reflect a signal but how would it change the frequency? Shouldn't the transmitter and dog houses be tuned to 1500? Interfering with stations 5 and 10 channels away is really really "wideband" for a well tuned AM transmitter. Also shouldn't the stonewall audio filter (old style audio chain) or the box that functions as the AGC / limiter limit the audio bandwidth part of the signal to less than 10 khz?
BTW Souldn't the Night Site be moved to "undevelopebel or farm land" 10 or 15 miles miles east and the current site be developed$$? If they are building buildings close enough to mess with the pattern, someone is doing business in the area. It appears that there is decent soil conductivity and in the direction part of the pattern you could expect a lot more (power) than original 50 KW blasting towards downtown to keep the coverage strength "legal".
BTW Souldn't the Night Site be moved to "undevelopebel or farm land" 10 or 15 miles miles east and the current site be developed$$? If they are building buildings close enough to mess with the pattern, someone is doing business in the area. It appears that there is decent soil conductivity and in the direction part of the pattern you could expect a lot more (power) than original 50 KW blasting towards downtown to keep the coverage strength "legal".
There really haven't been any major buildings built in the area recently. There's a few low rise buildings in the area. That's about it. This appears to be an illegitimate reason for the issue.
The night location is across the street in a wetland. No future development opportunity there.
The night location is across the street in a wetland. No future development opportunity there.
Screenshot of SDR spectrum located ~4 miles west of the 1500 KSTP tower site. 3-22-26 22:15 utc, KSTP on day tower.
I live about 4 miles from the 1500 KSTP tower site. The wideband splatter related to 1500 KSTP has been an ongoing problem for several years now. I casually reached out to KSTP a numbers of times over the years, as well as finally filing a report with the FCC back in 2024. After a number of emails with the FCC, I was put in contact with an engineer at Hubbard. We had a good phone call where I was told they were aware of the problem and confirmed my findings, but were unable to find the source of the problem. One theory is re-radiation from a nearby structure, perhaps related to the substation that is located a few thousand feed north-northeast of the site.
The splatter extends down below 1130 and can be heard up into the 160m ham band. The splatter occurs on both their day tower and the night array. The frequency response of the wideband splatter changes slightly between the day and night tower, with that affecting 1130 shifting up to affecting 1180-1260. I can minimize or nearly eliminate the splatter when I carefully place 1500 KSTP in the null of my loop antenna. Once you get beyond 7-10 miles away from the tower site, the splatter is virtually undetectable. Driving around the area listening to local stations on 1130, 1330, 1440, 1470, and 1570 Semi-local 1550 WEVR has become largely unlistenable. I used to like to put them on a 1953 Sentinel tube table radio that I have in my living room.
I was told I was the only one to have ever reported the issue before. So I encourage anyone else who has experienced this splatter to reach out and let them know about it as well.
One clue as to the source of the splatter could be this strong burst of noise that tends to occur every hour to an hour and a half. The burst always lasts just over 10 seconds, every time. It acts as if something is turning on then back off. It matches the frequency response of KSTP's overall splatter. I've seen and heard it on my SDR as well as on my car stereo while driving around the area.
Burst of splatter/noise. 3-22-26 23:12 utc, KSTP on day tower.
Burst of noise again nearly an hour later at 00:11 utc. KSTP still on day tower.
Anyone have any idea as to what in the broadcast chain may potentially generate a ~10 second burst of noise every hour or so?
Here is KSTP switching from their day tower to the night array about a minute later at 00:12 utc:
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If I remember my highschool physics from five plus decades ago, reflection can have an impact signal strength at a give point but to create a bunch of harmonics I believe another signal would be involved or some kind of refraction from a surface that would act like a giant prism which is really strange. Some physics master or doctorial person might research this and possibly right a paper on this. Another weird possibility. Is there some kind of shortwave or three or four letter government agency site near? If none of the above are true (most likely) being several states away these are what I would recommend which are "Old School". Hopefully they have done this but some engineers are better with laptops than transmitters. I'm not ragging out anyone but with all the digital equipment today, a station engineer had better have his / her's digital stuff together along with RF knowledge.
Assuming this station isn't digital, or a shared site, first I would check the audio chain output feed into the transmitter making sure the bandwidth of the total audio is under 9k. Then to eminate the transmitter, if they have a back up transmitter, run it early one Saturday or Sunday Morning in the directional pattern then after sunrise non directional and look at signal. Look at both OTA signals of the spare transmitter. If still crappy signal, does the daytime signal go through the directional phasing cabinet, if so rig up a dummy test load directly from the spare transmitter not using the phasing cabinet. Then run the spare with programming (during non peak electric rates if you are subject to peak power rates). You should be able to SAFELY* scope the signal. If it's clean then make sure the output of the phasing cabinet is clean, SAFELY* look at the outputs of the phasing cabinets at input of the ATUs.
*Messing around with RF is dangerous and can be deathly. Always have someone who can kill the power as a "safety" net. You don't want to be a "hotdog" being cooked like the videos have shown in the past.
Assuming this station isn't digital, or a shared site, first I would check the audio chain output feed into the transmitter making sure the bandwidth of the total audio is under 9k. Then to eminate the transmitter, if they have a back up transmitter, run it early one Saturday or Sunday Morning in the directional pattern then after sunrise non directional and look at signal. Look at both OTA signals of the spare transmitter. If still crappy signal, does the daytime signal go through the directional phasing cabinet, if so rig up a dummy test load directly from the spare transmitter not using the phasing cabinet. Then run the spare with programming (during non peak electric rates if you are subject to peak power rates). You should be able to SAFELY* scope the signal. If it's clean then make sure the output of the phasing cabinet is clean, SAFELY* look at the outputs of the phasing cabinets at input of the ATUs.
*Messing around with RF is dangerous and can be deathly. Always have someone who can kill the power as a "safety" net. You don't want to be a "hotdog" being cooked like the videos have shown in the past.
I submitted a complaint today. We shall see if anything happens.
I reported a situation like this to the chief engineer of an AM station many years ago that had spurs similar to this. He fixed it within a matter of minutes! There were only two main spurs, and they were symmetrical each side of the main carrier. I had a similar experience hearing CKJD 1250 Sarnia, ON. I could hear the spurs 65 miles away, with very distorted audio, but not the main carrier. CKJD was extremely directional, and it was not receivable on 1250. I called CHOK 1070 to see if they noticed anything, but they hadn't. Also CHLO 1570, a spur in the 1600s, distorted, heard near the Straits, 250 miles away, at Night.
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Nitroengine: Do you run one of the Minneapolis-area Kiwis? If so, THANK YOU. That's how I roll tape on WEVR, or what I call "a trip back to a simpler time". Nothing on that playlist is newer than 1994-1995. You'll hear a lost Bruce Hornsby or Carly Simon song, followed by an easy listening cover of "How Deep Is Your Love" or "Isn't She Lovely". Don't forget those Freeman Drug ads and the hourly state forecasts for MN and WI. If I lived in the WI suburbs of MSP, they would be my #1 preset.
Yes, I know I'm a radio geek. But I wonder how many businesses in downtown River Falls and Hudson play WEVR all day long? Especially with MAJOR competition just 30-40 miles west.
Yes, I know I'm a radio geek. But I wonder how many businesses in downtown River Falls and Hudson play WEVR all day long? Especially with MAJOR competition just 30-40 miles west.
I have mine unlisted. I use it much of the day to listen to WCCO, WDGY and other locals and semi-locals, and I fill it up with my own connections to DX at night. The "Bikedork" Kiwi has been online for a good number of years now. Playing around on that Kiwi is one reason why I had to get my own back in 2020. The one in Plymouth came online within the past two years or so, that one is decent too. The Kiwi is not only cool since you can access it remotely through any browser (even on your phone!), but it's a damn sensitive receiver too. I've seen it compared to expensive SDRs like the Perseus SDR, and it easily holds its own for AM DX.
I keep my Kiwi in the wideband ±20 kHz mode so I can open it up for full 10 kHz audio.
I hope WEVR never changes. They remind you of how stations used to sound decades ago. Complete with the decades old news intros. "WEVR and WEVR FM Stereo" although I've been told the FM hasn't been in stereo for quite a few years now. Their AM signal actually sounds pretty good with good processing.
The Kiwi also decodes C-QUAM, so I can get the most out of 540 WXYG who runs AM stereo, which comes in best here during the winter months.
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WEVR probably has a larger audience than you think. To my knowledge, they are the only station to carry Brewer’s games in the metro. They also carry Packer games. Not sure I’ve ever heard them in River Falls businesses. I heard WDGY in stores all of the east metro.