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U.S. & Australian Over-The-Horizon HF RADAR

Discussion in 'Amateur Radio News' started by KA0KA, Mar 23, 2019.

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  1. KA0KA

    KA0KA Ham Member QRZ Page

    I just finished two videos showing the US Navy AN/TPS-71 and JORN HF RADAR signals. Satellite images of arrays are included in videos. I want to thank both K3DCW & N1SZ for all their help in signal identification and other. Other signal videos will live on my youtube channel.

    The Jindalee Operational Radar Network (JORN) project was started by the Australian Defence Science and Technology Organisation (DSTO) now called the Defence Science and Technology (DST) group in the early 1970s [UK spelling]. The system is reported to operate from 5 to 30 MHz and can be seen using FMCW modulation ‘common’ 3kHz & 10kHz sweeps and various Pulse Repetition Frequency and length (64 pulse). Power is a reported to be a combination of 20kW P.A.’s times 28 feed to the high/low band wire vertical log periodic arrays for a total of ~560kW. It can be frequency agile with a distinctive single center carrier burst as seen in the video.

    JORN currently consists of 3 main OTHR transmitters and receivers in Queensland and Alice Springs covering 90 degrees each and Western Australia extends through 180 degrees jointly operated from the JORN Coordination Centre at RAAF Base Edinburgh, South Australia by No 1 Radar Surveillance Unit (1RSU). System also incorporates vertical incident sounding for propagation management and uses several transponders.

    Western Australia receiver array is massive, by my count has nearly ~994 dual monopole elements arranged in two rows nearly 6kM in length as seen in satellite images attached in video.
    The US Navy AN/TPS-71 Relocatable Over-The-Horizon RADAR (ROTHR) was initially contracted to the Raytheon Corporation in 1984 with subsequent contracts to upgrade and support growing program developments. The system is reported to operate from 5 to 28 MHz and can be seen using FMCW modulation ‘common’ 8kHz & 16kHz sweeps and various Pulse Repetition Frequency and length. Power is a combination of summing ten 20kW solid state P.A.’s (each consisting of four individual 5kW P.A.’s) for a total of ~200kW feed to the high/low range wire vertical log periodic arrays. It is extremely frequency agile and at times has a three pulse carrier into burst as seen in the video.

    AN/TPS-71 uses a bistatic transmitting and receiving system with remote command and control via the main Operations Control Center providing both sea and air surveillance sectors called Dwell Information Regions.

    The term “relocatable”, was used to describe the generators, transmitters and receivers. Receiver array has 372 dual monopole elements arranged in two rows nearly 2.6kM in length confirmed via satellite image. System also incorporates vertical incident sounding for propagation management.

    Some interesting over-the-horizon forerunners were projects: US Naval Research Laboratory (NRL) MADRE; WARF; AN/FPS-95 (COBRA MIST); AN/FPS-112 and AN/FPS-118.

    Received here in Fort Collins, CO on Apache Labs Anan 8000DLE.

    Enjoy, Tyler KA0KA
    KT2I, VU3JNM, N0TZU and 5 others like this.
  2. KQ6XA

    KQ6XA Ham Member QRZ Page

    Great work, Tyler!
  3. WQ4G

    WQ4G Ham Member QRZ Page

    What is 'propagation management?'

    Dan KI4AX
  4. M0ODV

    M0ODV Ham Member QRZ Page

    Great Tyler.I saw your last post on CODAR and other radar types and i stumbled upon one of your video's on AN/TPS .ive heard that on HF for decades and wondered what that was.Thanks for the educational lessons.Me grasshopper.I learn from the master.tyvm.
    Guess you know HAARP is back on air.?

    Last edited: Mar 26, 2019
  5. N1SZ

    N1SZ QRZ Lifetime Member #233 Platinum Subscriber Life Member QRZ Page

    Propagation management is exactly what it sounds like, using propagation information to ensure that the desired signal reaches the right target area for the OTHR. Not unlike trying to determine which band the DX will be on based on time of day, etc.. Same mentality. As the propagation changes throughout the day, so will the operating frequency.

    Hope this helps.

    Jim, N1SZ
    KM4MDT, K7DIP, WA1ZMS and 1 other person like this.
  6. WQ4G

    WQ4G Ham Member QRZ Page

    Seems like propagation forecast would be a more appropriate term for what you describe. But, I'll take your word for it.

    Dan KI4AX
    N6SPP likes this.
  7. M0ODV

    M0ODV Ham Member QRZ Page

    Update on HAARP.
    The next university of alaska research campaign is scheduled for March 25 to 28th.between 2.7 and 10Mhz.and has recently been transmitting SSTV and Voice. Transmissions are scheduled early wednesday morning.

    02:00:00 - 02:11:00: 3.20Khz
    02:11:30 - 02:16:30: 3.35Khz & 2.80Khz
    02:17:00 - 02:22:00: 3.35Khz & 2.80Khz
    02:22:30 - 02:32:30: 3.35Khz & 2.80Khz
    02:33:00 - 02:39:00: 4.40Khz & 4.50Khz
    02:39:30 - 02:45:30: 4.40Khz & 4.50Khz
    02:46:00 - 02:56:00: 5.10Khz & 6.90Khz
    02:56:30 - 02:59:30: 3.20Khz

    Subject to change..foF2 ionospheric forecast.
    Last edited: Mar 26, 2019
  8. K9CTB

    K9CTB Ham Member QRZ Page

    Wow ... thanks for the great sleuthing, Tyler ... I would love to be a RADAR tech working with this stuff .... but I'm not going to a recruiting office to do so!! :)
  9. W8AAZ

    W8AAZ Ham Member QRZ Page

    Our side is blasting HF with radar . Well, with friends like that.....
  10. N1SZ

    N1SZ QRZ Lifetime Member #233 Platinum Subscriber Life Member QRZ Page

    Unfortunately, forecasts are just that. Forecasts=guesses. OTHRs are dynamic, they use real-time information from ionosondes to adapt to the current propagation environment.

    KM4MDT and KT2I like this.
  11. ZL4IV

    ZL4IV Ham Member QRZ Page

    So why do we respect the frequency allocations and they do not? As arrogant as the Communists were during the cold war!
  12. AI3V

    AI3V Ham Member QRZ Page

    The ionespheric sounders give real time info on propagation.

    A weather analogy would be walking outside and seeing if it was raining, as opposed to forcasting a 36% chance of sunshine next week based on past weather.

  13. KC8UD

    KC8UD Ham Member QRZ Page

    There is one of these signals on 3974 KHz every morning tearing up the band. I'm listening to it right now as I write this. It was making our NET very difficult to conduct this morning. How are these things legal?
  14. AA5CT

    AA5CT Ham Member QRZ Page

    re: "on 3974 KHz"

    What do the WARC Region 1, 2 and 3 radio allocation charts show as primary?
  15. KH6KG

    KH6KG Ham Member QRZ Page

    Chirp sounding the ionosphere for MUF, LUF, FOT in real time

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