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When One HD Radio Signal Interferes With Another Station
I admit this is a bit above my knowledge, but I still found it interesting - and some with an engineering bent may find the same thing. It's the story of how HD Radio has been occasionally interfering with the main signal of radio stations and why it's happening. (One of the examples involves WDCX-FM in Buffalo, incorrectly called WDXC in the article.)
"Two cases were documented: a Class B FM in Buffalo, N.Y. and an LPFM licensed to Asheville, N.C. In both cases, HD-equipped radios tuned to the respective frequencies of these two stations (not transmitting a digital carrier) were forced into their HD reception mode, with programming being delivered from stations in the neighborhood of 100 miles away."
I seem to recall a few threads here in the past where some posters complained about an HD signal suddenly overtaking the station they were listening to as they drove in a fringe area. Apparently it happens more often than you'd think.
All this comes amid debate about whether the FCC should allow for higher power signals on HD - and if that could wind up interfering with signals where adjacent stations already aren't the strongest.
An interesting article, especially for those with the background to get all the subtleties of what the author is talking about.
HD Radio Capture Issue Is Not Always Predictable
- rk12
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Re: When One HD Radio Signal Interferes With Another Station
HD radio transmits in the adjacent channels above and below the actual frequency potentially interferring with 2 other FM stations.All HD radio should be equipped with HD reception off setting so hijacking can be turned off.DAB was a much better,wish Canada stayed with it.
- RadioAaron
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WDCX's HD is also the reason 99.5 in K/W went HD. Fight fire with fire.
- Marc1178
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WCLV Cleveland still takes out CBC Radio One in Sarnia from time to time on a HD Radio. Both are on 90.3 FM.
Analog to digital interference is also a thing. The HD on 97.1 from Detroit doesn't decode where I live because there are standard FM broadcasts on both 96.9 (WBTI) and 97.3 (Smile FM).
- haydenmatthews14
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RadioAaron wrote:
WDCX's HD is also the reason 99.5 in K/W went HD. Fight fire with fire.
I think it was a horrible idea for 99.5 to be on that frequency. Wasn’t there any other frequency avaliable? Or did they had to go with 99.5. Because the 2 strong stations from K/W are 96.7 and 105.3. 91.5 is somewhat strong but static at times.
- mace
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WDCX's HD is also the reason 99.5 in K/W went HD. Fight fire with fire.
I think it was a horrible idea for 99.5 to be on that frequency. Wasn’t there any other frequency avaliable? Or did they had to go with 99.5. Because the 2 strong stations from K/W are 96.7 and 105.3. 91.5 is somewhat strong but static at times.
91.5 is a surprise frequency in Toronto. Depending on the weather, you might get Kitchener, Barrie or Rochester. None exceptionally clear.
- haydenmatthews14
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Re: When One HD Radio Signal Interferes With Another Station
WDCX's HD is also the reason 99.5 in K/W went HD. Fight fire with fire.
I think it was a horrible idea for 99.5 to be on that frequency. Wasn’t there any other frequency avaliable? Or did they had to go with 99.5. Because the 2 strong stations from K/W are 96.7 and 105.3. 91.5 is somewhat strong but static at times.
91.5 is a surprise frequency in Toronto. Depending on the weather, you might get Kitchener, Barrie or Rochester. None exceptionally clear.
I didn’t know Barrie and Rochester NY had stations brodcasting on 91.5. What are they?
- Skywave
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99.5 was originally assigned to Larche Communications for CIKZ-FM. It experienced severe thermal ducting problems, particularly in the summer, and in 2005 was approved to change frequency to 106.7.When CKKW AM on 1090 applied to flip to FM in 2008, it applied for 99.5 because it was the only frequency available.
In 2018, the CRTC in its wisdom turned down an application for a power increase by CKKW-FM to 37.5 kW. This would have gone a long way to resolving the problem.
- Saul
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I didn’t know Barrie and Rochester NY had stations brodcasting on 91.5. What are they?
91.5 CBC Radio 1; Rochester WXXI (NPR, classical).