Tag Archives: WWVH

Paul discovers Firedrake in an unexpected place

(Photo: Satdirectory.com)

(Photo: Satdirectory.com)

Many thanks to SWLing Post contributor, Paul Walker, who writes:

From time to time, I get some interesting shortwave catches here in Alaska.

Sometimes on 10 MHz, I get WWV. Sometimes I get WWVH. Sometimes I get BPM China. And from time to time, I’ve heard all three at once.

Well this clip is something a bit different…

From April 20, 2016 at 1707 UTC here is my Tecsun PL880 connected to a 225 foot long wire with audio set at 3.5 kHz while tuned to 10,000 kHz (10 MHz).

This time, I am hearing WWVH Hawaii and […] the Chinese Firedrake jammer. What’s happening is Firedrake is jamming the Sound of Hope on 10005 kHz and the signal is so wide, it’s [competing with] WWVH.

I am making no adjustments to the dial tuning or audio settings as this happens. Listen to how things fade in and out.

Click here to view on YouTube.

Updated release: “At The Tone: A Little History of NIST Radio Stations WWV & WWVH”


Almost five years ago, I wrote about a unique collection of archived recordings called At The Tone: A Little History of NIST Radio Stations WWV & WWVH.

Producer Myke Dodge Weiskopf recently released a new and expanded edition of At The Tone which is now available for purchase and download.

Myke describes the update:

“The new edition significantly expands on the previous CD reissue from 2009. It incorporates a bunch of tapes sourced from the original announcer tracks made by Jane Barbe herself for WWVH, as well as a handful of vintage broadcast recordings previously left out of the set. I’ve also taken the opportunity to clean up and remaster the set overall, so it’s a much more cohesive listening experience as a body of work.”

Click here to purchase the new digital edition of At The Tone.

Please comment!

Myke is also giving away a free download of At The Tone to a lucky SWLing Post reader!

Simply comment on this post, noting the first time you heard WWV: note both the year and the model of receiver used.

For example, I would comment: “The year was 1976 and the receiver was an RCA Model 6K3 console radio.”

Myke will pick a winner from the comments next Wednesday (November 25th). If the winner has already purchased the expanded edition of At The Tone, Myke will reimburse the purchase. Good luck!

Recording the 2015 Leap Second

Fullscreen capture 6302015 115321 PM

Yesterday, I posted a brief article about the leap second that occurred between 23:59:59 June 30, 2015 and 00:00:00 UTC July 01, 2015.

I decided to record the leap second on as many shortwave time station frequencies as possible. The only viable options for me–based on time of day and my reception location–were the WWV frequencies 10, 15, 20, and 25 MHz, and CHU frequencies 7,850 and 14,670 kHz.

I was able to record four different time station frequencies simultaneously on the TitanSDR Pro.

I was able to monitor four different time station frequencies simultaneously on the TitanSDR Pro. (click to enlarge)

Unfortunately, HF propagation was very poor yesterday, so the higher WWV frequencies–20 and 25 MHz–were completely inaudible, as was CHU on 14,670 kHz. There were numerous thunderstorms in our area, so static crashes were prevalent.

Still, since this was a first attempt to record a “leap second,” I didn’t want to take any chances.  I had the Titan SDR Pro monitoring and recording two CHU and two WWV frequencies [screenshot], the Elad FDM-S2 recording WWV on 15 MHz [screenshot], and the WinRadio Excalibur on WWV’s 10 MHz frequency, as well as recording the whole 31 meter band spectrum [screenshot].

In the end, the strongest frequencies I captured were CHU on 7,850 kHz and WWV on 15,000 kHz. WWV on 10,000 kHz was much weaker than normal and the band was quite noisy–still, it’s readable, so I included this recording, too. Recordings follow…


Photo I took in 2014 of the sign above WWV's primary 10 MHz transmitter.

The sign above WWV’s primary 10 MHz transmitter (2014).

All of the recordings start just before the announcement of 23:59 UTC.

WWV added the extra second and higher tone, then continued with their top of the hour announcements, including a note about leap second (which begins after the 00:04 announcement). CHU simply injects a one second silence before the long tone.

WWV on 15,000 kHz using the Elad FDM-S2:

CHU on 7,850 kHz using the TitanSDR Pro:

WWV on 10,000 kHz using the WinRadio Excalibur:

One interesting note about the 10 MHz WWV recording above: I believe I may be hearing BPM China in the background. I’m curious if anyone can confirm this because I don’t know BPM’s cadence/pattern well enough to ID it.

Other recordings…?

Did you record a shortwave time station as leap second happened? If so, please comment, and feel free to share a link to your recording!

Hang on a second…seriously


One of four WWV time code generators in late August, 2014

Tonight, for the first time in three years, we will experience a leap second. What is a leap second?  Wikipedia provides a concise explanation:

A leap second is a one-second adjustment that is occasionally applied to Coordinated Universal Time (UTC) in order to keep its time of day close to the mean solar time, or UT1. Without such a correction, time reckoned by Earth’s rotation drifts away from atomic time because of irregularities in the Earth’s rate of rotation. Since this system of correction was implemented in 1972, 25 such leap seconds have been inserted. The most recent one happened on June 30, 2012 at 23:59:60 UTC. A leap second, the 26th, will again be inserted at the end of June 30, 2015 at 23:59:60 UTC.

Like many of you, when I think of time–or UTC–I think about the NIST radio station WWV in Fort Collins, Colorado.

I had the honor of visiting the facility last year (yes, photo tour still forthcoming!).  During the tour, my guide and Chief Engineer at WWV and WWVB, Matthew Deutch, told me that he’s always going to be on site come Leap Second!


WWV’s Matthew Deutch with WWVB antennas in background

I wrote Matt this morning to ask what were his plans tonight?  His reply:

“The leap second happens at 0000 UTC tonight, which is 6:00 pm here in Fort Collins. All of the programming took place at the beginning of the month, so the equipment is armed…we just sit back and watch for the leap this evening.

Even though it is automated I hang around the station to make sure everything goes smoothly at the critical moment…”

WWV-First-Sign-SMMatthew closed his message by wishing me a “Happy Leap Second.”

Back at you, Matt! We hope that second leaps as smoothly as you’d like!

Not to put Matt on the spot, but you can listen to WWV (or the atomic clock of your choice) make the leap second tonight at 00:00 UTC. As for me, I’ll hop on 10 MHz and 15 MHz to hear (and hopefully record) the extra “tick.” At the end of this post, I’ve provided a list of time stations for your convenience.

Happy Leap Second!


WWV 20 MHz Collins transmitter

List of shortwave radio time stations

  • CHU Canada: 3330 kHz, 7850 kHz, 14670 kHz
  • BPM China: 2,500, 5,000, 10,000, and 15,000 kHz
  • HLA South Korea: 5,000 kHz
  • BSF Taiwan: 5,000 and 15,000 kHz
  • WWV (Ft. Collins)/WWVH (Hawaii) United States:  2,500, 5,000, 10,000, 15,000, 20,000 and 25,000 kHz


Click here to listen to Leap Second recordings from WWV and CHU.