Re: LF: EbNaut beaconing on LF from JN80

[IZ7SLZ <iz7slz.domenico@gmail.com>]

Hello Michel,

The SL recorder function (thanks Wolf !) takes input from FFT and performs (i think) the inverse-FFT and all necessary calculations (including any lags) in order to align the audio with the time-stamp.

The user (me) have just to invoke the command "wave.record" to start and stop recording. Of course the PC system time must be cured with an NTP or with a GPS 1pps+nmea.

SR=111.1187..... comes from the decimation of the actual sample rate of the audio card (48003.28 mean60). 

In these links you can find four SL configuration pages related to the recorder, in use in my setup now:

https://www.dropbox.com/s/j8gefgosqo11jmf/Screenshot%202016-06-04%2013.33.03.png?dl=0
https://www.dropbox.com/s/y4w2cwfxssttbz4/Screenshot%202016-06-04%2013.33.51.png?dl=0
https://www.dropbox.com/s/7rvhhrthk4emha5/Screenshot%202016-06-04%2013.35.34.png?dl=0
https://www.dropbox.com/s/wvcoey08xfq2xl1/Screenshot%202016-06-04%2014.08.43.png?dl=0

All the best

Domenico, iz7slz


On 6/4/2016 3:22 PM, Michel Brunel wrote:

Hello Domenico,

When recording EbNaut samples, do you have to compensate for the lag due to the huge decimation factor ?

In other words is it ok or not, to start recording your H:00 transmission  at H-1:00 and stop recording at H:15 ?
Another question: how do you achieve the sr=111.118706906 of your WAV files ?

Thanks,

Michel - f5wk


Le samedi 4 juin 2016 à 12:06:15, IZ7SLZ écrivait :

> Good day LF,

> I have activated a beacon on 137.485 kHz sending an EbNaut message every 
> 30 minutes starting at .00 and .30.
> Message lenght is 13 characters at 1 s/symbol. Coding = 8K19A
> Duration is 14'56"

> Carrier is on 1 minute before each transmissions and off at .45 and .15

> My  receiver is also tuned around 137.500 kHz and it is programmed to 
> record EbNaut.

> Recording audio from the receiver, prearranged for EbNaut-rx direct 
> usage, is available at this DropBox folder

> https://www.dropbox.com/sh/9c3nnw40nyb5pqc/AABZ6oPxpAY4IwuWFmebMSfba?dl=0

> Each (15 minutes) audio file is named with the date and time of its start.

> I will try to keep active the beacon for the week end.

> Report are welcome.

> 73 and good WE all,

> Domenico, iz7slz






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