A couple of years ago, WWVB, the National Institute of Standards and Technology radio station that sends out time signals 24 hours a day, seven days a week on 60 kHz, celebrated it’s 50th anniversary. At the time, I was interested in building a WWVB receiver, but when I found out that it wasn’t easy to do, my enthusiasm waned.
Well, a couple of days ago, a reader e-mailed me. He asked, “Have you seen this Everset Technologies User’s Guide ?” and attached a PDF of the ES100 Application Development Kit. According to the document, the ES100 Application Development Kit (ADK) is a “dual-antenna receiver module for the phase-modulated time-code signal that is broadcast from the WWVB radio station.”
I replied that no, I hadn’t seen that, but while it does really look interesting, it looks like it’s vaporware. The URL given in the user’s guide, eversetclocks.com, doesn’t seem to be working. Googling “Everset ES100” returns links to a couple of posts on the time-nuts mailing list, a press release announcing the first shipment of ES100 ICs, and even a LinkedIn profile for some guy that worked at Xtendwave/Everset. None of these, however, produced any promising further information.
While researching this post, I happened to come upon the website for C-Max Time Solutions. I believe that this is the company that sold the CMMR modules. It looks like they’re still selling WWVB receiver chips. They have two different ones, the CME6005 sells for $3, and the CME8000 sells for $3.75. They also sell antennas and other related stuff.
Another approach would be to hack an existing WWVB clock. I describe a couple of approaches in my original post. The most promising seems to be the time-nuts post that describes how to hack a Sony Dream Machine AM/FM radio and liberate the WWVB receiver module. This module uses the Temic U4226B Time Code Receiver IC. Unfortunately, this IC seems to also be no longer available.
I was thinking about hacking the Radio Shack WWVB clock that I have, but it didn’t look like I’d be able to pry the case open without destroying it, and I don’t really want to destroy it at this point. Another source might be thrift shops. Here in Ann Arbor, the Kiwanis Club operates a weekly “rummage sale,” and there are several other thrift shops in the area. I plan on doing a little thrift store shopping soon to see if I can find a used WWVB clock. If any of you happen to have one of these WWVB clocks or WWVB receiver chips that you no longer want, I’d be happy to make you an offer for them.
More VLF fun
Yesterday, while on my Saturday morning walk, I had my HT and was talking to Ed, KD8OQG, and Thom, W8TAM, about this e-mail exchange. Ed and Tom are both SDR enthusiasts, and at one time, Ed and I were talking about building a Blitzortung lightning detector, which detects VLF emissions of lightning strikes.
We got to thinking that this might be possible with some kind of SDR receiver and an appropriate converter. Thom is going to look into this.
And, talking about lightning detection, we got to thinking that we might be able to include lightning detection in this project as well. According to the National Lightning Safety Institute, “Various detector detection receiver algorithms operate at different frequencies and wavelengths: Boltek Stormtracker in the Low Frequency range 100-700 kHz; Vaisala GAI NLDN at 100-400 kHz; NMT Lightning Array at VHF 60-78 MHz; LIS and OTD optical at 777.4 m; Vaisala SAFIR VHF 109-119 MHz; Vaisala GAI LDAR II at 50-120 MHz; GAI VLF at 20-50 KHz; the UK Meteorological Office RDI at 9.8 KHZ; etc. NASA has published an excellent summary of families of lightning detectors.”
That’s where we are right now. More to come, I hope.