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Loggings => ID and Translation Requests => Topic started by: Matt_B on July 18, 2018, 1844 UTC

Title: UNID 9965 khz 1837 UTC 18 July 2018
Post by: Matt_B on July 18, 2018, 1844 UTC
Just heard this over the Northern Utah SDR.  I think it's Radio Free Asia, but I'm not sure....some help with the ID?

https://drive.google.com/open?id=10MEVmTMtqGgHc4fZVa1niQUkjswa45ys (https://drive.google.com/open?id=10MEVmTMtqGgHc4fZVa1niQUkjswa45ys)
Title: Re: UNID 9965 khz 1837 UTC 18 July 2018
Post by: ulx2 on July 18, 2018, 1933 UTC
This is so-called Chinese Firedrake jammer:

https://www.hfunderground.com/wiki/Firedrake (https://www.hfunderground.com/wiki/Firedrake)
https://www.sigidwiki.com/wiki/Chinese_Firedrake_Jammer (https://www.sigidwiki.com/wiki/Chinese_Firedrake_Jammer)
Title: Re: UNID 9965 khz 1837 UTC 18 July 2018
Post by: MDK2 on July 19, 2018, 1401 UTC
This is a good opportunity to give a little primer about Chinese jamming.

The Chinese are determined to keep undesired broadcasts from reaching their citizens' ears. To that end, they seem to use very high power jamming signals, at least in comparison to the ones being blocked, and I think that they may use multiple transmitters on a single frequency when they do. This is based on the fact that sometimes I hear echoes that are reminiscent of what you hear when you get both short and long path, but the delay seems just a bit shorter. Not at all a scientific observation, I realize.

Anyway, why does this matter? Because most of the time China uses a stream of China National Radio 1 (CNR1) to jam. (If you hear the Firedrake, then you know right away. Most stations transmitting from outside of China to that country don't have music - and if they do, it's not an uninterrupted hour of it.)

If you don't speak Mandarin, you're not likely to know the difference. So, how can you tell if you're hearing RFI or VOA or something else that the schedule lists? You have to tune in to other frequencies and make comparisons. And you may need to get on some online SDRs located in East Asia to check. Another good thing to do, in the case of RFA, is go to their site and find the Mandarin language stream. The delays make comparing the audio a little tricky, but usually the difference is pretty obvious, especially after a minute or so.

The thing I do is look either for CNR1 on the schedule, or any listing of "CNR1/Firedrake Jammer" on the Eibi schedule, and see if they're playing the same thing that I'm hearing. This is valuable if the "CNR1/Firedrake jammer" listing is concurrent with a DIFFERENT station than the one listed. The main ones that get jammed are VOA in Mandarin, RFA in Mandarin or Tibetan, and Radio Taiwan International (RTI) in Mandarin. The Firedrake is often used against RFA, but not the others.

Sadly, 99% of the time you're hearing jamming. That has to be your assumption when you first find a broadcast that's supposed to be RFA, RTI, VOA, or some others that have Mandarin broadcasts with the Far East as its target, and you have to work to prove that it's NOT a jamming signal before you log it.

The way I came to realize how much effort China puts in this is.... last year, RTI had an English broadcast on either 7445 or 7455 (I'm forgetting which - it's not on anymore) at 1100 UTC, which I could copy with a fair signal most mornings here in Denver. At 1200, they switched to Mandarin, while staying on the same antenna with the same power and direction. And at that time all of a sudden, came in this HUGE signal, which I could find in many other frequencies, primarily in the 49m band. It was the CNR1 jammer. It showed me how much more power they use than Taiwan, which I think was listed as having a 100 kW signal.
Title: Re: UNID 9965 khz 1837 UTC 18 July 2018
Post by: R4002 on August 07, 2018, 1821 UTC
Good post, MDK2.

China figured out that the Firedrake jammer was a lot easier to note as a jammer, whereas jamming with the CNR 1 audio gives them plausible deniability that they're "accidentally" "interfering" with whoever they're jamming, as opposed to outright jamming (which is what Firedrake obviously is). 

It would be interested to hear how much power the Chinese are pumping into the HF spectrum that's entirely jamming.  If RTI is transmitting with 100 kW and the Chinese are obliterating it with CNR1 audio they've gotta be doing 500 kW or more (probably with directional antennas too). 

Since the Russians are more interested in jamming GPS, mobile phone and two-way radio/military tactical radio systems, that leaves the Chinese and the North Koreans as the big jammers.
Title: Re: UNID 9965 khz 1837 UTC 18 July 2018
Post by: MDK2 on August 07, 2018, 1834 UTC
Good post, MDK2.

China figured out that the Firedrake jammer was a lot easier to note as a jammer, whereas jamming with the CNR 1 audio gives them plausible deniability that they're "accidentally" "interfering" with whoever they're jamming, as opposed to outright jamming (which is what Firedrake obviously is). 

It would be interested to hear how much power the Chinese are pumping into the HF spectrum that's entirely jamming.  If RTI is transmitting with 100 kW and the Chinese are obliterating it with CNR1 audio they've gotta be doing 500 kW or more (probably with directional antennas too). 

Since the Russians are more interested in jamming GPS, mobile phone and two-way radio/military tactical radio systems, that leaves the Chinese and the North Koreans as the big jammers.

Thank you. I'll add that Cuba is no slouch on the jamming game. I understand that Saudi Arabia is as well, but I don't think most western SWL'ers ever really get to hear that very often. But really, nobody touches the Chinese.
Title: Re: UNID 9965 khz 1837 UTC 18 July 2018
Post by: R4002 on August 07, 2018, 1909 UTC
I can understand the jamming targets of the Cubans (Radio Marti, VOA and maybe some others?) and the theoretical targets of the Saudis, but I was unaware that Saudi Arabia actually engaged in shortwave jamming. 
Title: Re: UNID 9965 khz 1837 UTC 18 July 2018
Post by: MDK2 on August 09, 2018, 1501 UTC
I can understand the jamming targets of the Cubans (Radio Marti, VOA and maybe some others?) and the theoretical targets of the Saudis, but I was unaware that Saudi Arabia actually engaged in shortwave jamming.

They target Iranian broadcasts that are in Arabic. I've heard it on a kiwi SDR that's in Qatar. It's a siren like whoop. As you know, there is no love lost between those two nations.
Title: Re: UNID 9965 khz 1837 UTC 18 July 2018
Post by: ulx2 on August 17, 2018, 1214 UTC
Jamming of Zahedan on 9650 kHz, 1 Jun 2018 (http://ulx2.byethost24.com/wp-content/uploads/2018/06/VOIRI-Jamming1.mp3)
Jamming of Sirjan on 9790 kHz, 1 Jun 2018 (http://ulx2.byethost24.com/wp-content/uploads/2018/06/VOIRI-Jamming2.mp3)