Close to the limit and could not be done with any other mode. The average signal was only 15dB in 19.5 uHz! But at least we now have a stake in the ground at 6.47, I can probably squeeze another dB
Thanks, that was useful against the low daytime noise. I'm having fun with the H field rx, it's not working so well at 6.47 compared with 8.27. E field is doing well. At 8.27 usually H has the bette
Yes, still working on the 19 char message. I think I'm about 1.3 dB short of decoding it. Quite a challenge because overnight 7th/8th was very noisy. The last few nights have been quiet. Typical! --
Very strange. Only 30.5% symbol errors were counted, which is where the Eb/N0 = +5.1 comes from. But the carrier level: 11.2 dB in 24.0 uHz corresponds to Eb/N0 = -1.1 dB. The laws of physics have c
The Eb/N0 of +5.1 dB is correct. It was a very good signal and an easy decode. The 11.2 dB in 24.0 uHz is wrong: there's a mains harmonic in the passband of the background noise measurement. It's not
I haven't been able to decode this one. The average noise was 3.7 dB higher than the previous successful message, so there should still be a couple of dB to spare. I've tried a wider range of phase s
An easy decode of 'JN49IK' with Eb/N0 = +3.8 dB. Phase pattern: 30 30 0 0 Carrier S/N: 16.96 dB in 17.9 uHz Symbol errors: http://abelian.org/vlf/tmp/160514a.gif Now I know the message I can reverse
Reconstructed carrier of the successful 2016-05-14_21:40:02 message http://abelian.org/vlf/tmp/160515a.gif S/N is 19.15 dB. The unsuccessful message 2016-05-13_00:00:02 http://abelian.org/vlf/tmp/160
Yes, or better: keeping to 100s and going to a 16K mode instead of 8K for an increase of coding gain. About 65 months at the moment. But with a long message, an interruption of a few hours is not a d
I wasn't able to decode the 18 char message. Thanks to Markus for the sneaky decode, I was able to reverse the modulation to see the signal was 13.6dB in 8.8 uHz. That puts Eb/N0 at about -6.5 dB. St
Measurement of reconstructed carrier from the 31.5 hour message, In approximately 8 hour blocks (34.7uHz): From To Signal S/N Phase Noise 16th 21:00 17th 05:00 0.077 fT 11.0 dB 112.7 0.022 fT 17th 05
From 2016-05-21 04:00 to 16:00 the carrier at Cumiana was 14.6 db in 23.15 uHz. This is after a stage of vorbis compression so might be a dB or so better in the raw original. Good for 5 chars at 84 s
Just checked Wolf's VLF rx at Bielefeld, 2016-05-21 04:00 to 16:00 is 20.14 dB in 23.15 uHz. Worth 17 chars at 38 seconds for 0.0 dB. -- Paul Nicholson --
Yes some very noisy nights. Also plenty of rain here which means extra static in the E-field. I guess that's what we have to put up with to do these tests in summer! The rx has been running fine, no
Nothing. I have to admit defeat on both these transmissions. I've tried a range of beam headings and so on but I guess it's a few dB short of a decode. Some very noisy nights during these tests. I've
18.22 dB in 4.06 uHz, http://abelian.org/vlf/tmp/160604a.gif which gives Eb/N0 = -2.35 dB on the 20 char message 16.24 dB in 7.97 uHz, http://abelian.org/vlf/tmp/160604b.gif and Eb/N0 = -2.46 dB. See
New encoder and decoder software which changes the character coding slightly. http://abelian.org/ebnaut/ Windows sender is now V0.4, Windows decoder is V0.5, and the Linux software is at V0.7 Previou
That's encouraging as I contemplate the blank NoV application in front of me. It is necessary to supply some detail to calculate things like ERP and field strengths. Tricky without building and testi
