Am 27.10.2016 um 21:31 schrieb Paul Nicholson: I have used the Trimble Thunderbolt with its fixed 10uS pulse. It worked (vlfrx-tools, M-Audio 192) but timing jitter improved after a pulse stretcher i
Hello Paul, Thanks for the details. I guess the pulse jitter cannot go down much further, unless the GPS receiver can "pull" its own oscillator in frequency, which is definitely not the case with the
Hi Stefan, No significant improvement if the soundcard really supports 96 kHz sampling or more, and if the standard deviation in the GPS-based pulses is already below 100 ns. That is displayed on the
Hello Stefan, 857 ns standard deviation in the 1-second pulse timing at 48 kHz sample rate isn't spectacularly good, but considering the fact that the pulses are sent over a 'lossy' Vorbis-compressed
Hello Jim (and all GPS/SL users), I have just uploaded a new version of Spectrum Lab (currently V2.92 b01) which supports 'very short' GPS sync pulses. Tested with 10 us GPS pulses. This isn't descib
Hello VLFers and all, That's indeed a nice surprise, considering the low bitrate of the Vorbis-compressed audio stream that 'transported' Stefan's signal from here (Spenge-Bardüttingdort, near Bielef
Hi VLFers, Turn up the power, you may trigger a Whistler ... well, no, joking aside: At the moment there's an impressive whistler storm happening. Fascinating listening to Paul's internet VLF audio s
Hello Markus and all, Am 18.02.2017 um 18:19 schrieb Markus Vester: Thanks Wolf, there's indeed a beautiful Whistler festival going on! After having read the post on the VLF Group, I had listened in
Hi Eddie and all, If SL is unable to load the colour palette files, you should try installing it in a folder *outside* the usual 'programs'-thingy in windows. Quite likely the hyper-nervous 'operatin
Hi Stefan and all, If I had the option (and lots of spare time), I would have turned SL into something cross-compileable years ago. The problem is the entire user interface (display windows, dialogs,
Hi Luis, I have some old VLF spectrograms which clearly show the ZEVS FSK. Scroll down a few pages on this site: http://dl4yhf.darc.de/t/vlf_experiments.htm 73, Wolf DL4YHF . Am 28.05.2017 um 13:59
... and never forget to wind a 'secondary' over the current transformer, always terminated with low resistance. Otherwise you will quickly saturate it, which is something that NO current transformer
Greetings all, I received the following info from Murray, ZL1BPU, who asked me to forward this to the group since his messages don't seem to get through. 73 and GL, Wolf DL4YHF . New Digital Mode
Hi Paul and all, Thanks for all effort put into this, and nice to hear about the TA reception via my remote receiver at DF0WD. Paul asked: Wolf's receiver has been working very well the last few days
Hi Paul, Concerning the different performance of VLF7 / Bielefeld: having other equipment connected at the radio club? < I don't think, since there was no one at the club besides myself for only half
Hello Jack and all, capabilities. I wish I had a good file that worked at 8720kHz for QRSS600 as an example. This would be a good start if nothing else. < It's not that difficult to set up. The key p
Hi Jack, Yes, it takes several hours until the first spectrum (or line of pixels in the spectrogram) appears. To load a complete (FFT-) window for 47 uHz bin width, it takes 1 / 47 uHz = 21276.x s
Greetings all, Storm "Friederike" has taken her toll - the enclosure of my VLF6 had a small crack, so water slowly crept in, which slowly killed the high impedance input. It's in for repair now. Hope
Hi Stefan, Indeed - but for an existing design, the through-hole parts are favoured (just flip the JFET around if the pinout is Gate-Source-Drain instead of Drain-Source-Gate as for J310 vs BF245). I
Hello Paul and all, Thanks for the detailed analysis (even though the reason for the sampling-point jitter is still unknown). Perhaps it's time to start developing our own A/D conversion hardware. Th
