[ntp:questions] CHU/IRIG audio drivers

Max Power mikehack at u.washington.edu
Mon Jan 29 14:00:38 UTC 2007

Have you seen:

CHU can be improved upon, at least to the point of having 2 transmitter 

This at least would allow for transmitters at some sites to be turned off 
while others are turned on -- allowing for the upgrade to pay for itself 
with respect to the power bill.

> I've just gone through a round of audio driver upgrades for the WWV and 
> CHU radio services and the IRIG signal. The documentation has been 
> rewritten as well. I'm hoping that the CHU upgrade might find users in 
> Canada to support the continued operation of CHU with three frequencies, 
> even if the 7335 kHz frequency is moved. As it is, that frequency is 
> clobbered from sundown to sunup by broadcasters that should be using the 
> Internet.
> [...]
> In addition to the accuracy improvements, the radio drivers have better 
> behavior under marginal signal conditions, especially the 
> maximum-likelihood UART and majority decoder used in the CHU driver. As we 
> are at the nadir of sunspot cycle, propagation conditions have been truely 
> awful, but does present the opportunity to improve the algorithms to 
> separate weak signals from real trash.
> To Canada (my father was born there): get the CHU thing running and make 
> sure the NRC knows it.

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