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Loggings => Utility => Topic started by: Corvus on May 15, 2017, 1943 UTC

Title: Carrier pulse on 13.560
Post by: Corvus on May 15, 2017, 1943 UTC

Hearing solid S9 tick here in the mid pacific in the ISM spectrum that's not a listed time station that I can find. A carrier pulse on AM with no modulation. Double tick at the minute mark apparent on sidebands that matches WWVH.

Anyone else hear it or know about it?

Title: Re: Carrier pulse on 13.560
Post by: Dag on May 16, 2017, 2355 UTC

https://www.hfunderground.com/board/index.php/topic,20854.msg75763.html#msg75763

See if you can access the above link. I have heard pips in the 22 m ISM band that are very close the one second apart, with a double pip nearly at the one minute mark, but it seems to be of industrial application, not a time station.
Dag

Title: Re: Carrier pulse on 13.560
Post by: MDK2 on May 17, 2017, 0029 UTC

I can hear something very much like what Dag describes regularly when I'm at home. But I can take my portable receiver just a couple of miles away and not hear it any more. Someone once suggested that I could probably try to find it if I went around my area with it to see where it's stronger and where it's weaker.

https://www.youtube.com/watch?v=cQh6ReSZ5jA

Title: Re: Carrier pulse on 13.560
Post by: AlanC on May 17, 2017, 1854 UTC

13560kHz is the frequency used by many RFID devices and also Near Field Communications (NFC). It's possible that what you're hearing is an access control swipe card reader or a contactless card payment machine somewhere, or possibly just a mobile phone with the NFC turned on. These devices radiate quite a long way.

Loads of info here:

http://stackoverflow.com/questions/37649276/hf-rfid-vs-nfc-can-an-nfc-enabled-mobile-phone-read-high-frequency-rfid-tags

Cheers
Alan

Title: Re: Carrier pulse on 13.560
Post by: Corvus on May 17, 2017, 2050 UTC

Thanks for the info, 13.56 mhz is pretty obscure on Google search so thanks for the links. I shutdown NFC on all devices in the house and it persists, I'll have to take the sw-100 out for a walk and see if the source is localized.

Title: Re: Carrier pulse on 13.560
Post by: Strange Beacons on May 17, 2017, 2246 UTC

Quote from: Corvus on May 15, 2017, 1943 UTC

Hearing solid S9 tick here in the mid pacific in the ISM spectrum that's not a listed time station that I can find. A carrier pulse on AM with no modulation. Double tick at the minute mark apparent on sidebands that matches WWVH.

Anyone else hear it or know about it?

As of 2245 UTC, the "single tick" and then "double tick" can be heard just slightly beneath the central signal via the Utwente WebSDR (http://websdr.ewi.utwente.nl:8901/?tune=13560usb).