Thread: WWV & vhf/uhf
View Single Post
  #15   Report Post  
Old December 6th 12, 03:09 AM posted to rec.radio.shortwave
Arid ace Arid ace is offline
external usenet poster
 
First recorded activity by RadioBanter: Sep 2012
Posts: 21
Default WWV & vhf/uhf

On Wed, 05 Dec 2012 03:28:44 -0800, Bob Dobbs wrote:

Arid ace wrote:
On Mon, 3 Dec 2012 21:49:28 -0800 (PST), wrote:

[...]

We don't have any analog tv broadcasting since 2009 over here,in NYC. If WWV and its sisters like WWVB or WWVH cannot be used due to the phase modulation- I think the Canadian CHU still uses simple AM modulation or something very close to it.


The phase modulation used by WWVB is a bit messy. The value of 180 deg for all
data would be OK because multiplying the signal with itself would remove the
modulation. Unfortunately, the station ID uses 45 deg, see
http://en.wikipedia.org/wiki/WWVB
CHU might be the better alternative then, that the frequencies in use aren't a
multiple of 100 KHz or 1 MHz isn't a problem. With some creative calculation I
managed to lock both 153 KHz and 77.5 KHz to a 10 MHz VCXO so this case is
unlikely to be much different. 14670 and 7335 KHz would have my preference as
the first is twice the second so one receiver could easily use both signals.

Jan


CHU no longer uses the 7335 slot but has moved to 7850,
has been for over three years now.


Thanks, I didn't know that, having used European stations for decades.
Time to buy a rubidium based frequency standard (made in China of course) then
as that's both more precise and cheaper than a GPS based solution.