Antennas for System BLUE - Mini Guide

[RichoAnd]

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

[Dale.Reid]

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

[DelandeC]

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?

[Jorgeminator]

Great guide, thanks!

[Ronnyaj]

I'm building the breakpipe antenna. Should the two loops be connected at the top or insulated from eachother?

[RichoAnd]

Your choice - They may be collected at the top - it makes the structure more rigid

[WX3080]

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

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

[RichoAnd]

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

[Ronnyaj]

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.

[RichoAnd]

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.

[Egon]

For me it is also hard to believe, but it's not an antenna, its a probe, as Richo repeatedly emphasized.

Its exelent, thanks Richo!

/Egon

[chubros]

Hello to all...
Thanks for the mini guide Richo.
I just want to ask a few questions.
I want to make a mini loop for my blue system with 2 simple coax loops (no trafo small loop 38cm).
I dont have a clear connection guide to the blue board. Is it easy for anyone to make a simple diagram of the wiring ends?
May i use 2 or three of them? What about grounding? 
Thanks in advance and keep up your special job.

[Bofhenator]

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

Excellent guide, I have just signed up on the forums and for a system blue and think I'll start by building antennas and see what kind of VLF noise I pick up in my home.

I tried to access http://www.richos.dk/TOA but it seems to be down?

[bazzalight]

Richo,

I have started making the H field Copper tube Loop antenna shown in your mini guide and also from http://users.skynet.be/DanielV37/Project...m#Hardware.  I have produced 3D print files for the top & bottom Junctions from the drawings on that site and have published these files at http://www.thingiverse.com/thing:1713141 .  I have included attribution to the design as best I could find reference.  Can you have a quick look at this url and advise if any further attribution is needed.

thanks
Barry (Australia)

[Andrew.Instone-Cowie]

My Red and Blue are currently side by side, both with ferrite H field antennas. The Red were shielded with the plastic tube/copper tape method, and the Blue not shielded.

The Blue performance was not quite as good as the Red, so last weekend I swapped the antennas over so the Blue was shielded. The Blue performance hasn't really changed much, but the Red performance has dropped through the floor. So next weekend I'm swapping them back again! 

[RichoAnd]

Richo,

I have started making the H field Copper tube Loop antenna shown in your mini guide and also from http://users.skynet.be/DanielV37/Project...m#Hardware.  I have produced 3D print files for the top & bottom Junctions from the drawings on that site and have published these files at http://www.thingiverse.com/thing:1713141 .  I have included attribution to the design as best I could find reference.  Can you have a quick look at this url and advise if any further attribution is needed.

thanks
Barry (Australia)

Have a lot of suggestions for changes - water intrusion is a challenge

By the way - time has run from this antenna - it is too large, and intended for System GREEN
Make it of brake tube 5-6 mm and a diameter of ~ 40cm
Most effective is the "Möbius" with transformer

[chevyman142000]

What size PVC pipe are you using for the e-field antenna? I'm going to try and stop at Home Depot tomorrow to pick some up. Need to get mine out of the attic!

[RichoAnd]

32mm inside can do it

[pjb01]

Hi all,

I have a new System Blue (#1588) and have been testing H-field performance with a 2 axis wire loop antenna with 20 turns @ 38cm diameter (with the jumpers made on the back of the H-field antenna).

Can anyone comment on the relative performance between the simple loop antenna, and the ~40cm 'brake tube' möbius antenna that RichoAnd mentioned a couple of posts back?

Thanks,
Peter

[RichoAnd]

Minor difference if any