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Antennas for System BLUE - Mini Guide
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Many have questions about antennas
I made a mini guide to getting started making antennas Corrections reserved Good luck Richo http://en.blitzortung.org/Compendium/Doc...tennas.pdf ...If you wish I can help with ready-wound transformers 
2016-06-01, 01:04
Thank you, a nice summary and is updated for the BLUE system which helps.
I have been running only an E field antenna on RED for over a year after my H field got soaked and ate the board. I don't have strikes registering from around the world, but still reach from nearly the Canadian US border near me all the way down into the Gulf of Mexico and 100s of km out into the Atlantic Ocean. But, ferrites are fun to wind! Dale
2016-06-01, 06:49
Thanks for the guide.
How far from an aluminium mast should be the E-field probe if it is made of 10cm of 2.5mm² copper wire?
2016-06-10, 14:00
I'm building the breakpipe antenna. Should the two loops be connected at the top or insulated from eachother?
2016-06-10, 20:27
Your choice - They may be collected at the top - it makes the structure more rigid
2016-06-12, 08:15
(2016-05-31, 21:30)RichoAnd Wrote: Many have questions about antennas Dear RichoAnd, many thanks for putting together the antenna guide. I received my system BLUE yesterday and assembled it. Now I want to build the antennas I read your guide: http://en.blitzortung.org/Compendium/Doc...tennas.pdf I reviewed this page: http://en.blitzortung.org/cover_your_area.php I read the documentation: http://en.blitzortung.org/Compendium/Doc...B_14.1.pdf and the assembly guide: http://de.blitzortung.org/Compendium/Doc...B_20_1.pdf Question 1: 75 Ohm coax loop antenna (H-Field) Am I correct to assume that a complete coax loop antenna consists of three loops (not to be confused with wire turns)? And the connections are: A-1 = 1st loop conductor A-2 = 1st loop conudctor GND = 1st loop shielding (braid) B-1 = 2nd loop conductor B-2 = 2nd loop conudctor GND = 2nd loop shielding (braid) C-1 = 3rd loop conductor C-2 = 3rd loop conudctor GND = 3rd loop shielding (braid) Now, while all documents suggest three turns for each loop, the original instructions describe a diameter of 180 cm and your most recent guide 100 cm. Would a 180 cm diameter give a better reception? I have the attic space available. Or is 100 cm better to avoid noise etc.? What about the North South / East West directions? First loop N/S (A-1 and A2, second (B-1 and B-2) E/W and the third? Or will the arrangement be similiar to your recommendations for the ferrite rods, i.e. each loop 90° perpedicular to each other and no relation to the cardinal directions? Question 2: ferrite rod antenna array (H-Field) Your instructions state to arrange them 90° perpendicular to each other, while this page http://en.blitzortung.org/cover_your_area.php shows something else. Which ferrite antenna rod arrangement yields the best results? I'm sorry for these probably very basic questions. I just want to do everything correctly. Thank you! WX3080
Stations: 1471
2016-06-12, 10:29
Don't be sorry to ask
 The original 180cm was also made by me, but for an amp with much lower gain, and there it made sense (The GREEN System) All antennas in the "mini guide" are made for long distance. A loop antenna reach its maximum signal with the narrow side against lightning and minimum with the broad side against lightning. Between, the signal = cos(angle) - At 45° angle, the signal is dropped to ~ 71% Since the antennas is 90° relative to each other, the other antenna is now also at a 45° angle to the signal, and the signal on it is now also decreased to ~ 71% When the signal fall of one antenna, it increases on the other. With 3 antennas in a 60° layout as shown by the three ferrite antennas, the signal can fall to ~ 87% before one at the other antennas takes over. 71% or 87% does not matter in practice, so I use two antennas in an perpendicular arrangement. Direction relation to true north, is unimportant - Personally, I aim my antennas are NS / EW The third loop we are not finished discussing, in fact we are only just beginning :-) As with so much else in this project, the third channel joined because it was possible. We know that some nearby lightning has a horizontal signal, but at long distance they are damped pretty much. To investigate what happens to the near-by lightning, we must use a horizontal antenna, and that is WHY it is a good idea Do you have the desire and time, make a third as you place completely horizontally - let it be exactly the same size. 1-2 is channel 1 4-5 is channel 2 7-8 is channel 3 3,6,9, used for shielding The vertical antennas has no need to sit in a cross. In fact, it is possible to position three antennas so they can easily reach the amplifier. It is not a requirement for coaxial loops that they have very short wires to the amplifier. Since they are terminated with impedance of the cable, they can be quite long /Richo
2016-06-19, 12:28
What is the optimal length of the wire? 10 cm is fine but is It better with longer wire?
And the thikness of the wire. I use a 1,5 mm2.
Stations: 1489
2016-06-19, 13:52
Some think it should be longer, I think it may be shorter
Some think it should look like the "real" antenna - I do not care as long as it can measure changes in the electric field between ground and atmosphere. 10cm is a good length. 1mm² is a practical thickness - I use 2,5mm² because I had enough of it. |
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