On 3/19/2011 9:34 PM, Paul Christensen wrote:
<Major snip of excellent information> At least some AM stations operating with digital subcarriers are GPS locked and can be extremely accurate. WMAL 630 KHz here in the Washington DC area is one example. It's as close to 630 KHz as I can measure (about 10 milli-Hz) and E-mail correspondence with the station's chief engineer confirmed the transmitter frequency is GPS locked. I've measured other local AM stations as far as 16 Hz off - within the FCC's tolerance, but not of much use as a frequency standard. > Commercial AM broadcast station > frequencies are typically only accurate to about +/- 20 Hz although most are > better than that. > > Jack K8ZOA ______________________________________________________________ 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
