[time-nuts] Is there any IRIG-B hardware decoders available?

paul swed paulswedb at gmail.com
Tue May 14 17:43:14 UTC 2013


I pretty much doubt the SB ever went to the phase level. Really no need for
that the average offset and detection point on the AM signal was good
enough. I have done what was suggested just modulate a 1Khz signal though I
did use an xtal oscillator. It worked fine.
Regards
Paul.


On Tue, May 14, 2013 at 1:04 PM, Esa Heikkinen <tn1ajb at nic.fi> wrote:

> Chris Albertson kirjoitti:
>
>  NTP will so this.  There is an IRIG reference clock.  You really do
>> want to use NTP to discipline the PC's clock.  Almost every other
>> method is worse and causes time discontinuities.
>> If you happen to have TTL level IRIG it s very easy to convert it to
>> amplitude modulated IRIG.   The standard is a 1KHz tone.
>> Build a cheap 1KHz oscillator.  A 555 timer is good enough.  Then you
>> a single transister if IC time switch to modulate the amplitude of the
>> signal.  The details are not critical.
>>
>
> That's good idea if the phase of the 1 kHz signal is not critical?
>
> I checked the IRIG-B signal with oscilloscope and looks like the 1 kHz
> signal's phase is locked to the time signal. The bits will always start and
> stop at exactly same phase. That makes sense because with phase detector it
> could be possible to get very accurate timing from the 1 kHz signal - much
> better than following the amplitude only. That's one reason why I was
> interested about chipsets; if they can follow the phase also. I think if I
> design any hardware for that it should follow the phase also? It may be
> complex...
>
> Does anyone know if the soundcard based IRIG decoder will follow the phase
> also, or only the amplitude (?)
>
> --
> 73s!
> Esa
> OH4KJU
> ______________________________**_________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/**
> mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts>
> and follow the instructions there.
>



More information about the Time-nuts_lists.febo.com mailing list