Some signals on the band would be handy. Trying to test new E-field rx against old with the two planted side by side on a bleak moorland hillside. Needed some weak signal so made up a little near fi
A signal appears close to 8819.9 Hz at Forest VA. Doesn't look like Dex, frequency is not stable and not exact multiple of 0.1Hz. http://abelian.org/vlf/tmp/141211a.gif AA5BW perhaps? It would be qui
In a bandwidth more suitable for the width of the signal http://abelian.org/vlf/tmp/141211b.gif I think this is probably Dex running without GPS lock, the frequency offset is about right for the free
And neither is Dex so we have a mystery signal! Tomorrow I'll look back over the 10 day recording loop. Meanwhile the spectrum plot updates every 10 minutes at http://46.4.26.83/sp8820_vlf35.png -- P
Spectrogram covering 24 hours yesterday http://abelian.org/vlf/tmp/141211c.gif A wandering signal from a crystal source of average stability. These are fairly common when you dig deep enough into the
Spectrum at Forest VA, updating every 10 minutes http://46.4.26.83/sp8957_vlf35.png Timing system at Todmorden behaving badly on the E/W loop tonight. Soundcard rate xtal drifting due to drafts. If i
Last night Dex was testing at 9177 Hz. W4DEX at Todmorden and Bielefeld (DL4YHF) in 1 hour steps at 9177 Hz: Start Todmorden Bielefeld S/N Phase S/N Phase 22:00 10.4dB -39.3 5.8dB -62.2 22:30 11.7dB
At Cumiana Italy 44.96N,7.42E run by Renato Romero IK1QFK: Examining 9177Hz S/N and phase in 1 hour steps (278uHz) 20:00 2.9dB 20:30 3.2dB transmission started around 21:20 21:30 6.2dB -102.3 22:00 1
W4DEX transmitting 8822 Hz carrier 2014-12-15 20:50 to 2014-12-16 04:00 UT. Reception at Bielefeld Germany by DL4YHF http://abelian.org/vlf/tmp/141216a.gif This confirms a previous reception at 8820
Spectrogram of W4DEX at Forest, VA (Mike Smith KE4RJQ) showing a very strong signal at range 254km, http://abelian.org/vlf/tmp/141216b.png I played around with gnuplot to make this fancy 3D spectrogr
Another long transmission last night from Dex. Signal and noise at Forest, VA - KE4RJQ at range 254km http://abelian.org/vlf/tmp/141217a.png http://www.vlf.it/smith1/opticalink.html on Renato Romero'
Another night of poor reception further into Europe but, for a couple of hours W4DEX came out of the noise at Cumiana http://abelian.org/vlf/tmp/141218a.gif and averaged 11.4dB S/N in 139 uHz. Except
Last night was the best reception of W4DEX so far in Todmorden. S/N and phase in one hour steps - 19:00 -1.4dB 20:00 7.0dB -143.2 21:00 7.5dB 133.9 22:00 9.6dB 138.6 23:00 10.8dB 116.4 00:00 12.7dB 1
That's about right for a quiet night. That's after sferic blanking - before the blanker the background is some 20dB or more higher. The system noise floor is about 0.2 fT RMS in 1Hz. There happens t
Overnight 2014-12-18/19: The carrier was detectable in IK1QFK's on-line receiver at Cumiana from around 23:00 to 05:00 with a gap around 03:00. It barely shows up on a spectrogram though, http://abel
Last night: 2014-12-19/20 Cumiana IK1QFK - best S/N was 11.2dB from 00:17 to 05:47 in 50.5uHz, http://abelian.org/vlf/tmp/141220a.gif Signal was a bit lower than previous night and the noise a bit hi
Your last transmission I think was on 2014-11-07 and I just examined the recording: You were S/N 14.7dB in 278uHz between 12:00 and 14:00. Signal is strong enough to send data quite fast. You could u
No, the transmissions are invisible on a spectrogram. Really they are quite stealthy, they just look like noise. So I have to know the exact start time. I see some carrier from you which ends about
I searched for the message using start times between 11:00:00.0 and 11:00:02.0 but nothing decoded. The earlier carrier had S/N 11.7 dB compared with the 14.7 dB you had in November. Hopefully the S/
