Hi Joe,

we made it! But only with a lot of luck.

Using default frequency and samplerate parameters, I first looked for the DDS pilot in your nine files and noted the frequency offsets:

 file      pilot
hhmm    Hz

2208  .1157 (pilot turned on half-way)
2308  .1148
0008  .1147
0108  .1149
0208  .1156
0308  .1160
0408  .1162
0508  .1161
0608  .1161

Thus I concluded that your rx might have small enough drift over 22 minutes. Then I took the file for my last transmission (12110608.txt) and calculated nominal frequency and start time offsets:

freq: +0.1161 - 10.000 = -9.9839 Hz, 
time: 6:00:00.3 - 5:50:40.92 = 559.38 s.

You said that your clock was about 5 seconds slow, so I started searching around 554.4 s offset. The signal is too weak to be seen directly, and I hadn't sent any plain carriers before or after which would have helped finding at least the right frequency. After some playing around I focused on one of the nearby small blue peaks, and tweaked both offsets to center and maximize it more, but no decode happened. Then I tried shifting the timing in 2 second whole-symbol steps. Each time I waited for the decoder to work it's way through all the phase combinations, loosing more and hope with only gibberish decodes. Finally near the end of the third long run, suddenly my message "HELLO LF" stared back at me: Oh my god, we've really made it!  

Congratulations, Joe!

Let's call it a day now,
73, Markus (DF6NM)

Re: LF: EbNaut tests 137.490 kHz/OFFLINE 
Von: Markus Vester <[email protected]>
An: jcraig <[email protected]>
Datum: So, 11 Dez 2016 8:53 pm

Hi Joe,

thanks for the files! I have successfully downloaded them from your site, and will now start looking for possible signals.

Best 73,
Markus (DF6NM)



-----Ursprüngliche Mitteilung-----
Von: jcraig <[email protected]>
An: Markus Vester <[email protected]>
Verschickt: So, 11 Dez 2016 6:50 pm
Betreff: Re: LF: EbNaut tests 137.490 kHz/OFFLINE