Waking up early this morning, I took a look at Stefan's garden grabber http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_remote_Grabber.html and was greeted by a fascinating display on his VLF pane
Hello Markus, Thanks for your observation and article! :-) Most interesting. I can indeed confirm there were a number of cloud-cloud lightnings last night, up to 20 per minute were visible at times.
Hi Stefan, LF, we're not just playing around... I would rather consider this an original scientific experiment, perhaps worth proposing as an research project in environmental physics ;-) Frequency s
Hi Markus, Let's see what is possible. I'm trying to ground the far end of the inv-L to form a vertical loop. I guess that 20 A will be no problem at all but 100 A sound quite optimistic :-) Here is
Hello Markus, VLF, A few minutes ago i've grounded the far end of my antenna with a massive wire. This would handle 100 A :-) See https://dl.dropboxusercontent.com/u/19882028/VLF/20150721_211722.jpg
Hi VLF, Now i continued with measurements of the new loop. I took 3 different capacitors in series and searched for the maximum antenna current for a fundamental frequency. I had and have no idea abo
Markus, Am 18.07.2015 06:50, schrieb Markus Vester: The screenshot http://df6nm.bplaced.net/VLF/spherics/dk7fc_VLF_150718_1326.jpg shows a number of narrow tweek-mode resonances at multiples of 1.72
Hi VLF, Today I've built a transformer to match the antenna to the PA. This is not the ideal solution for QRO / highest antenna currents but i like to idea of a galvanically decoupled antenna and TX.
Hi Stefan....that is a really unique way to wind an RF transformer! Here's hoping it works as good as it looks! 73, J.B., VE3EAR LowFER Beacon "EAR" 188.830 kHz. QRSS30 EN93dr
Friday night (July 24/25) was stunning. Coming home from a beer after local midnight, I noticed spectacular VLF spherics resonances on the DK7FC remote garden grabber (screenshot http://df6nm.bplaced
Friday night (July 24/25) was stunning. Coming home from a beer after local midnight, I noticed spectacular VLF spherics resonances on the DK7FC remote garden grabber (screenshot http://df6nm.bplaced
Just FYI, i found that there was a certain correlation between transmitting and the arrival of the fire brigade (EMC issues)! When using a (linear) audio amp, nothing happend but the currents are sma
Genosse Markus, On 18.07.2015 06:50, Markus Vester wrote: ... a number of narrow tweek-mode resonances at multiples of 1.72 kHz. These are obviously spherics from nearby lightnings, bouncing multiple
Hi Peter, thanks for this! Amazingly, the 1.68 kHz spaced bands are visible all the way up to about 40 kHz. All the best, Markus (DF6NM) From: [email protected] pws Sent: Saturday, August 15, 2015 7:27 PM
I had to wait a while for a UK thunderstorm. I didn't get sharp resonances like those on Stefan's spectrogram, except for a short period about an hour after the storm. By that time it had moved away
Hi Paul, That may be essential for H-field reception. But I'm observing those effects very often on an E-field rx without any thunderstorm activity nearby. See (lower left): http://lf-radio.de/misc/t
