Re: VLF: EbNaut on 6470.1 Hz

[Markus Vester <markusvester@aol.com>]

The transmission was decoded from DL0AO data (well, just!):

ebnaut-rx V0.5
input file dl0ao_04140130.wav
sample rate 0.514393 per second
rx frequency 6470
file start time 2017-04-13 21:05:19.620
polynomial 16K21A
crc size 18
number of chars 2
block size 30
symbol period 36.000
number of symbols 800
list length 200000
start offset 3288.000
freq offset 0.100000
cores 2
skipped 3287.372330 seconds to start
padded 235.229 seconds at end
initial reference phase -77.0
---------------------------------------------
.....
found xx
list rank 25047
reference phase  120  150  150  180
carrier RMS 5.550e-005 noise RMS 1.627e-005
carrier S/N 10.66 dB in 34.7 uHz
carrier Es/N0 -18.37 dB
carrier Eb/N0 0.09 dB
info bit period 2526.32 seconds
symbol error rate 367/800 = 45.875 %
Es/N0 from symbol errors -20.0 dB
Eb/N0 from symbol errors -1.5 dB
Shannon capacity 2.1 bits/hour
Shannon efficiency 68.4 %
symbols file dl0ao_04140130-symbols.csv
elapsed 988 seconds

Hint: The message content is similar but not identical that from March 29/30.

Best 73,
Markus (DF6NM)



-----Ursprüngliche Mitteilung-----
Von: DK7FC <selberdenken@posteo.de>
An: rsgb_lf_group <rsgb_lf_group@blacksheep.org>
Verschickt: Do, 13. Apr 2017 23:53
Betreff: VLF: EbNaut on 6470.1 Hz

VLF,

OK, there are still some improvements to do on the new system but now these 8 stacks (8 x 33 T106-52 cores inside the field, they have a weight of 8.13 kg!) are inside the field. The actual resonance frequency is 20 Hz down but that's OK for tonite.
At least the antenna current stays at 460 mA for tonite.

Let's try a first EbNaut message on 6.47 kHz (not the first for Paul and me but for Eddie and maybe Jacek...):

f = 6470.100000 Hz
Start time: 13.Apr.2017   22:00:00 UTC
Symbol period: 36 s
Characters: 2
CRC bits: 18
Coding 16K21A
Duration: 8h
Antenna current: 460 mA

73, Stefan