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suggestion: add 25 MHz to list of time stations

edited April 2020 in KiwiSDR Discussion
Although WWV stopped officially transmitting on 25 MHz decades ago, it still transmits there unofficially. Since it's one of the few stations transmitting continuously on such a high HF frequency during this part of the sunspot cycle, I find it a useful beacon for band openings. I hear it in San Diego every time there's an E-skip opening (like right now). In fact I'm hearing WWV on all 6 frequencies, which is pretty unusual.

Comments

  • I didn't realize they were back on 25. Interesting.

    For historical reasons the content of the "select band" menu (and the band bars above the dx labels) is driven by the javascript file in /root/kiwi.config/config.js This file is created if missing (e.g. on the first software installation) but not touched after in case the Kiwi admin makes any modifications. So I will add 25 MHz to the template file. But for existing Kiwis the file will have to be edited by hand to make the change. Just duplicate the line for 20 MHz and edit to be 25 MHz.

    config.js existed before there even was an admin interface. That's how far back it goes. At some point the correct thing to do would be the read the (potentially customized) file and integrate it into the existing admin interface.
    WA2ZKD
  • edited April 2020
    Matt, N0RGT, one of the (I think) three who regularly man all 7 of the Fort Collins NIST transmitters, WWVB and the six HF WWVs, put 25 MHz back on the air in 2014
    http://www.arrl.org/news/wwv-s-25-mhz-signal-back-on-the-air
    The 25 MHz antenna is a fairly simple monopole slightly north of the transmitter building and nothing spectacular but it does provide a very useful upper-HF signal for reference. Not only do I often use it here (only 20 km distant) for level/sanity checks but it has been very useful with distant KiwiSDRs. For example, I managed to catch that signal as the MUF between Colorado and California was just getting to 25 MHz. At that time I was able to observe on one of the KPH Kiwis both the signal coming up out of the noise but *also* the propagated band noise either side of 25.000 MHz increasing with coherent QSB. This greatly increased confidence that the particular Kiwi and its antenna system was in fact DX noise limited - rather the holy grail of receive sites.

    Locally having constant sources of ERP allows investigating the effect of take-off-angle and foliage attenuation. At zero degrees the ERP of the six HF transmitters does not follow their estimated radiated power. Even at N6GN/K2 which is LOS to the entire length of all the NIST HF antennas upper-HF signals are weaker by several dB than free-space theory would predict. I presently attribute this to the take-off-angles of both the NIST antennas and the receive site (even though it is 2500' higher and on a steep slope in the WWV direction).

    It's really nice to have reference signals!

    Glenn n6gn
  • Hi Glenn, long time no hear!

    jks, thanks for the pointer to the config file. I can probably suggest some other changes, but i want to verify them first. E.g., the US Coast Guard has shut down all of the DGPS reference stations -- not just the DGPS hardware but the entire transmitting stations. They say modern GPS has made them obsolete.
  • at the same time, eLORAN is being explored rather than have GPS be a SPoF.... !
  • Are any LORAN-C signals still on the air anywhere in the world? I haven't heard one in over 10 years, since the US shut down its system in 2009 or so.
  • I have very occasionally heard one or two US LORAN stations on the air for what I assume are tests. I have not seen announcements of these, just luck that I checked 100 kHz and found them on the air.
  • Wow, I thought all the transmitting stations had been demolished.
  • edited September 2020
    There was recently a discussion about GRI 99600 (Wildwood): https://www.mail-archive.com/time-nuts@lists.febo.com/msg07726.html
  • jksjks
    edited September 2020
    With the exception of Anthorn (UK) they are mostly in Eastern Europe, the Middle East and Asia now:
    http://df6nm.bplaced.net/LoranView/LoranGrabber.htm

    Don't forget that the Kiwi has an extension capable of displaying the GRI pulse chains (but not providing any navigation solutions).
  • I am aware of testing of eLORAN stuff in CONUS
  • So what transmitting stations still exist in North America, even if they're not operating?
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