locked Re: occasional FT8 no decode, new computer? #raspberryPi #decode #Windows10


Bill Somerville
 

On 27/08/2021 14:39, Jim Pennino via groups.io wrote:
Hi Bill,

You keep assuming I am running something like SNTP.

I am not.

The system runs NTP and has an attached USB GNSS receiver that keeps the system to within about 3 milliseconds absent any other time source, but it also uses two local stratum 1 NTP servers that keep the system to well within 100 microseconds when it is on the network, which is most of the time. The system clock does NOT drift outside the microsecond range.

Perhaps if I rephrase the question: Would it have much effect on the resources used if the documentation suggestion to run something like NTP was changed to a requirement to keep the clock within, say 100 milliseconds or so?
Jim,

if I am assuming something then it is because you have not provided sufficient information. Note that saying your PC clock is always within 100 ms of UTC doesn't tell me you are running a full NTP implementation. What is sure is that a step adjustment to the PC clock during a receive period will cause an audio stream discontinuity, and that in turn may disrupt all decoding for that period. You asked what might be the cause of occasional failures to decode any signals, I offered one common reason. If that is not the case for you then you need to look for other causes, audio discontinuities are still likely to be the cause so perhaps some peak of CPU or interrupt loading is disrupting smooth audio streaming.

73
Bill
G4WJS.

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