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Chinese Jamming Reception of Radio Free Asia Broadcasts

Wednesday, January 3, 2007

As I mentioned the other day, I have been receiving what I believe to be a grayline propagation broadcast of Radio Free Asia (RFA) programing to the Uyghur region of China from Tajikistan every evening around dusk. However, I had not been able to positively ID it, as the programing was just music.

Well, I spent quite a bit of time researching this to try to confirm the original. I download Uyghur music to see if it sounded similar to the music programing I was getting (it did), I searched for and listened to the RFA Uyghur broadcasts to see if they matched (they didn’t), and I contacted Radio Free Asia to ask them about their Uyghur programing.

In particular, I asked RFA if their Uyghur included any musical programing, or if it was just news (all I could find on their website was news archives). They responded very quickly that they only program news in their Uyghur broadcasts . When I replied to thank them, and mentioned that I was receiving musical programing on that frequency, they responded that I was most likely picking up the Chinese jamming the signal (they have a new jamming station in Kashgar), to block the RFA broadcasts into the Uyghur region.

Once they mentioned that, it made sense. I had noticed the night before that the musical programing was the same every day. The programing was also just an hour of music, with no news or station identification.. It looks like the Chinese just play the same hour of music at the same time and frequency as the RFA broadcasts into the Uyghur region.

Anyways, if you are interested in listening I am picking it up in San Francisco from about 0120 UTC to 0150 UTC on 7480 Khz.

I have also uploaded a snippet of the Chinese jamming of the Radio Free Asia broadcast from January 2, 2007.

Finally, here is a map showing the gray line through San Francisco at dusk (notice it goes right through Tajikistan. (click image for larger version). The map was created with DX Atlas.

While I am a little disappointed that it was not the RFA broadcast (which I could have received a QSL card for), it was actually a lot of fun trying to figure out where the signal originated from, and is one of the reasons I am getting hooked on DXing with my shortwave.

Btw, if you are interested, the RFA website has a cool do it yourself tutorial on how to make an anti-jamming antenna.

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