[time-nuts] Is it sensible to update every few seconds from NTP server?

shalimr9 at gmail.com shalimr9 at gmail.com
Thu Nov 8 01:42:38 UTC 2012


That sounds odd, as most radios take tens of millisecond, if not hundreds to switch from transmit to receive and back in any mode other than break-in CW.

Further JT65 is used with propagation modes that typically do not have a stable or predictable propagation time like moonbounce or meteor scatter, so I don't understand why mS timing would be necessary?

I must be missing something.

Didier KO4BB


Didier

Sent from my Droid Razr 4G LTE wireless tracker.



-----Original Message-----
From: David Kirkby <david.kirkby at onetel.net>
To: Discussion of precise time and frequency measurement <time-nuts at febo.com>
Sent: Wed, 07 Nov 2012 5:47 PM
Subject: Re: [time-nuts] Is it sensible to update every few seconds from NTP server?

On 7 November 2012 23:28,  <bjones0 at mindspring.com> wrote:
> We had a presentation at our radio club several months ago on digital HF
> modes, and part of the presentation was on JT65 and apparently it needs
> a precise synchronized time fix on both ends for an exchange to occur.
> I do not recollect all of the details that were presented, but they did
> say that the default windows time keeper is not accurate enough, and
> advocated installing a third party ntp client that updates (way too)
> frequently.
>
> -Brian

I think it might be JT65 he is using. I know he said that if your time
was accurate to 1 ms, and someone elses 2 ms, you have a higher chance
of making the QSO. Hence there is a need for accurate timing. (I'm not
sure he said those exact figures of 1 and 2 ms, but the general point
was that it needed to be accuate, and increased accuracy gave a higher
chance of making the QSO).

But the whole idea of getting time from an internet time server every
few seconds seemed odd to me. He is not using any local time server.

I'll try to find out what mode he is using, and what software to
correct his time.

Dave

_______________________________________________
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.


More information about the time-nuts mailing list