Hello all, As you may have heard my 27 m vertical crashed in the hard winds we had recently. I have now built a new one, 23 m high and with larger diameter of the tubes (200-160-125-100 mm). I have a
Some new information from SSA news bulletin: "The radio station in Grimeton will be active on the following times: Jan 01 2000: 12.00, 12.30 and 13.00 UTC. Jan 02 2000: 06.00 UTC. Each transmission w
Lots of antenna ideas can be found at: http://www.patents.ibm.com/boolquery A search for "VLF" gives 70 hits in US patents, e.g. "Low height VLF antenna system". 73 Christer SM6PXJ
Hello all, I have a small question. What stops us from beginning experimenting on, say, 8 kHz? If I have understood things right, frequencies below 8,999 kHz is not allocated by the ITU, neither regu
Hello All, I believe most of the LF guys have a rotary loop antenna. Couldn't we make some observations on the direction of the unknown signal and then compare the results? Or is the signal too weak?
Hello Lowfers, Today I received permission from the authorities to transmit between 7-8,5 kHz with maximum 1kW out from the transmitter. "The transmitter shall be designed according to the regulation
Sometimes I use my sound card as a VLF receiver, using Spectrogram and the antenna connected to the mic input. It would be nice also to listen to the signals. What software/procedure to use? 73 Chris
I have some thoughts concerning loading of a vertical. Often it is impractical to use centre loading. Assume I have an existing 20 m high vertical. Take a wooden pole, 10 m high. Put a loading coil a
I came across an article from "Electronics World" Feb 1990. "Reducing mast height at MF". Tuned counterpoises are treated and some real world references are given. I can send a scanned copy upon requ
Hello (V)LF experimenters, I have an idea of resonating my existing vertical on 8 kHz. Is there a practical way to construct a 600 mH loading coil, withstanding 3-4 A and high voltage? Any *large* to
Hello, I just worked OH1BS and OH7OL on 136. OH7OL/Reino lives in Joensuu in the very eastern part of OH. His QTH should make him attractive for the distance record hunters. I like his antenna descri
Well, what is the ... ahem ... expected input V x I to the drains of your final transistors, gentlemens? Assuming a PA efficiency of 0.1%, of course ... Actually we have a special permission from the
Hello All, Last weekend I made some field strength measurements on my own station. http://home5.swipnet.se/~w-54761/fs.htm I use an untuned loop and a selective level meter. The output from the loop
Hello All Thanks to PA0SE for suggesting the calibration method. I tried this method this evening and believe I'm somewhat closer to the truth... Obviously the measuring loop with the connection wiri
If you calibrate the loop it is not nessecary to use an untuned loop. If you use a tuned loop the output voltage will be much higher (factor Q, can easily be 100 or more). This will allow to measure
OH2LX: Just curious - how do you calculate your Fs. P=0,0111*(E*d)^2 (P in W, E in mV/m, d in km) Main point is that you have very good signal!! Maybe. Just interested to see if it is possible to mak
