>Those tones are not sine waves. I wasn't so sure about this. Over the years I've never heard this mentioned, and technical references like NIST 25-67 and 668 describe the audio tones as being derived from the cesium standards, with no mention of harmonic content. So I sent an email to WWV asking if the audio tones were generated as pure sine waves or had harmonic content added intentionally. I quickly received this response: ------------------------------------------------------ Thanks for your email.
The audio tones on the WWV broadcast are derived from the station frequency standard, and are pure sine waves. Detailed information on the WWV broadcast can be found in NIST publication SP432, available for download on the webpage: http://tf.nist.gov/general/pdf/1383.pdf Sincerely, Glenn Nelson National Institute of Standards and Technology Radio Stations WWV/WWVB ----------------------------------------------------- I also see the harmonics on the P3. Unless Mr. Nelson is misinformed, I suspect that it may be the "harmonics" are distortion products, either transmitter IMD or artifacts of the receiver (P3 in this case). BTW the publication he mentions is a very good read for WWV listeners. Bob NW8L >Those tones are not sine waves. They have distinct harmonic content >that makes them a little "sharp" sounding, rather than the soft sound >of a pure sine wave. What you're looking at is the components that >make it sound that way. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
