73 to all...
Inviato da iPhone
> Il giorno 23/set/2015, alle ore 02:04, IZ7SLZ <[email protected]> ha
> Hello LF,
> I am pleased to report a successful "Coherent BPSK" QSO between DF6NM and
> IZ7SLZ on LF using EbNaut program of Paul Nicholson.
> QSO took place in the night between Friday 2015-09-18 and Saturday 2015-09-19
> I think it was the first time that anyone tried this on 137 kHz !
> Frequencies used were 137510.00 Hz (DF6NM) and 137502.12 (IZ7SLZ).
> We exchange messages of 16 characters in coherent BPSK with UT synchronous
> symbols, using a symbol period of 1 second and 8K19A scheme coding.
> Software used were the Windows' versions of EbNaut-TX and EbNaut-RX (tnx to
> P. Nicholson: your software is working without problems!).
> Also Spectrum Lab (tnx Wolf !) was used to export FFT data, in a similar way
> of the Markus' OPDS setup.
> Other programs, written by Markus, were used: one to convert FFT exported
> data for the EbNaut entry and another to search for the best frequency and
> time offsets.
> There was not much phase drift during the qso and in other test
> transmissions, since we reach a good frequency stability at both ends thanks
> to Rubidium Reference Oscillator (Markus side) and a good quality OCXO from
> my side.
> You can see reported symbol / carrier EbN0 and also the messages exchanged,
> in the attached screen-shots taken at both ends.
> We hope now to joint other stations that want to challenge the timing and
> frequency accuracy, to have a QSO in LF close to the Shannon limit.
> Markus DF6NM, will report soon all particulars and his comments of the
> experiment. Thanks in advance Markus!
> 73, Domenico (iz7slz)
> <EbNaut LF QSO 19-09-2015.rar>