[time-nuts] Interesting frequency standard project

Al Wolfe alw.k9si at gmail.com
Sat Jul 5 12:56:03 EDT 2014


    As stated AM stations in US must maintain 20 Hz accuracy. Most are well 
within that tolerance. I have measured many AM station's frequency as a 
function of my employment before retirement.

    Now comes HD radio. While the merits of HD AM radio are very much open 
to debate, one benefit is that the equipment for HD is GPS locked. If you 
can find an HD AM station you can probably bet they are very close to being 
on frequency. The ones I have measured have been right on and push the 
limits of my test equipment.

Al, retired, mostly
AKA k9si


> Date: Sat, 05 Jul 2014 06:20:36 -0400
> From: "Dale H. Cook" <starcity at plymouthcolony.net>
> To: time-nuts at febo.com
> Subject: Re: [time-nuts] Interesting frequency standard project
>
> At 06:27 PM 7/4/2014, Hal Murray wrote:
>
>>>... we have no requirement for that level of stability on the MW 
>>>broadcasts.
>>
>>How stable are they?
>
> That varies greatly from station to station depending upon what 
> transmitter they are running. Note also that compliance with the 20 Hz 
> accuracy requirement varies so you would only want to use stations owned 
> by companies with a good record of compliance with Part 73.
>
> Dale H. Cook, Contract Engineer, Roanoke/Lynchburg, VA
> http://plymouthcolony.net/starcityeng/index.html




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