Blue H field Ferrite antenna in L or Delta shape?
#1
Assembly instructions linked from http://en.blitzortung.org/cover_your_area.php
say to put the 2 (or maybe 3) ferrites at 90 degrees.

The picture on the same page http://en.blitzortung.org/cover_your_area.php
shows the ferrites in a 120 degree delta

What should I do?
Have I missed some documentation/description somewhere ?

thanks
Stations: 1685
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#2
(2016-11-02, 10:23)nellyt Wrote: Assembly instructions linked from http://en.blitzortung.org/cover_your_area.php
say to put the 2 (or maybe 3) ferrites at 90 degrees.

The picture on the same page http://en.blitzortung.org/cover_your_area.php
shows the ferrites in a 120 degree delta

What should I do?
Have I missed some documentation/description somewhere ?

thanks

Have a look into the Assembly instructions chapter 4.2: Antenna
Scroll down and you will find a picture with 2 horizontal ferrite antennas 90° and one vertical in 90° to them Smile
73 de Hartmut / DK5LH

Stations: 1582
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#3
(2016-11-02, 10:40)elythomaslumber Wrote:
(2016-11-02, 10:23)nellyt Wrote: Assembly instructions linked from http://en.blitzortung.org/cover_your_area.php
say to put the 2 (or maybe 3) ferrites at 90 degrees.

The picture on the same page http://en.blitzortung.org/cover_your_area.php
shows the ferrites in a 120 degree delta

What should I do?
Have I missed some documentation/description somewhere ?

thanks

Have a look into the Assembly instructions chapter 4.2: Antenna
Scroll down and you will find a picture with 2 horizontal ferrite antennas 90° and one vertical in 90° to them  Smile
Thanks, but I realise you can put two horizontally at 90°, and optionally put a 3rd at  90° to them....
but....
why the picture of three in a delta.? There is no description of deltas in the instructions ?
Which one should I be building
Why the picture of the delta if they are all meant to be at  90°
Stations: 1685
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#4
(2016-11-02, 10:47)nellyt Wrote:
(2016-11-02, 10:40)elythomaslumber Wrote:
(2016-11-02, 10:23)nellyt Wrote: Assembly instructions linked from http://en.blitzortung.org/cover_your_area.php
say to put the 2 (or maybe 3) ferrites at 90 degrees.

The picture on the same page http://en.blitzortung.org/cover_your_area.php
shows the ferrites in a 120 degree delta

What should I do?
Have I missed some documentation/description somewhere ?

thanks

Have a look into the Assembly instructions chapter 4.2: Antenna
Scroll down and you will find a picture with 2 horizontal ferrite antennas 90° and one vertical in 90° to them  Smile
Thanks, but I realise you can put two horizontally at 90°, and optionally put a 3rd at  90° to them....
but....
why the picture of three in a delta.? There is no description of deltas in the instructions ?
Which one should I be building
Why the picture of the delta if they are all meant to be at  90°

I have read in a post somewhere in the forum (maybe it was Egon) that it makes not a big difference if there are 2 or 3 ferrites. As you can see on my webpage I'm using 2 on ground level . Both are schielded to the south side due to my home Big Grin  in the back but I still receive a lot of signal from the south direction. At the moment there is low activity in Europe but when comming closer to Italy Spain, France... I'm always on page 1 - 3 seen on the station-list (http://de.blitzortung.org/station_list.php?session=1) whis very good efficiency.

The complete system is not only plug and play and I would recommend that you will start with 2 or 3 horizontally as you can see on my picture. I started with a piece of hard-paper, fixed the ferrites on it with some cable ties and tested for some days on different positions. I you have found a good position you can try with one vertically. Don't use them all vertically mounted on a wall. Check each position and configuration really for at least 1-3 days to get a valide response since the conditions will change all the time with the lighnings, noise, weather,...
So take your time until you have found the best position at your location. Then finalize it (and make it nice Big Grin Cool ). I recommend also to start with automatic settings. If you start with manual settings you will have too many variables changed at the same time.

 If you have  neighbour station check his results, compare and find a new location.


Good luck!
73 de Hartmut / DK5LH

Stations: 1582
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#5
(2016-11-02, 10:47)nellyt Wrote: Thanks, but I realise you can put two horizontally at 90°, and optionally put a 3rd at  90° to them....
but....
why the picture of three in a delta.? There is no description of deltas in the instructions ?
Which one should I be building
Why the picture of the delta if they are all meant to be at  90°

There are no rules, build something, see how well it performs or suffers from local interference at your location. Modify, retry, rinse and repeat.   Shy

Two antennas at 90 degrees to each other isn't very good here. Aim the null of one at an interference source and the other is useless. Currently two of my loops only have about 30 degrees between them, seems to be working fairly well. Getting used for a few location calculations for strikes the far end of the Med, 2,750 miles away...
Cheers
Dave.

Stations: 1627
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#6
elythomaslumber gives a bit of great advice...
Meanwhile...
The BLUE H field amplifier will accept 3 loops. The Red system accepts 2   Standard installation 'omnidirectional' reception of more prevalent, stronger, Vertically polarized impulses requires at least two (ferrites) mounted horizontally, at 90°...  or 2 (round or square, e.g.) wire/coaxial loops mounted 'vertically' to capture the H (M) component of desired vertically polarized impulse. This results in 4 directional lobes of best sensitivity. These 2 antennas are connected to the first two channels of the Blue preamplifier.

If you add a third H antenna on the third channel, and orient the loops at 120° DELTA (or 60°, as some would reference) you now have 6 lobes of best sensitivity, and would improve 'omnidirectional' sensitivity slightly over a 90° pair. This also affords a slight improvement in 'selectivity', in that now you may be able to adjust gains/thresholds/orientation to aid in minimizing an interference signal, in some cases, as my location, for example.

Part of the future implementation, and for experiment, is detecting and locating "Horizontally" polarized strokes. This is one reason for the third H field channel.. to capture the H(M) component of Horizontally polarized impulses. This requires a ferrite to be mounted 'Vertically" or a wire/coax loop to  be mounted Horizontally... and then connected to the third channel. The first and second channels would then be 'standard' 'vertically' polarized antennas at 90°

A single omnidirectional vertically mounted E probe/Amplifier can be added to detect the 'E" component (electrical) of the most common vertically polarized impulses.

An important note here:  BLUE SYSTEM - The 3rd channel of H field amplifier (on the controller) and the single E field amplifier share the same ADC.... (RED system operators with E field should be familiar with this confusing operation)... which means basically the 'lowest threshold' on either channel (H3 or E1) will be the threshold of the other ,,, you can follow our struggle with this a couple of years ago when E was added to RED... we finally figured it out... at this board: http://www.wxforum.net/index.php?topic=22710.0
                   TwinHollies WeatherCenter  Frankfort KY, USA
  Americas Operators at Sferics.us
        Stations: 689, 1439
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#7
(2016-11-02, 12:19)Cutty Wrote: An important note here:  BLUE SYSTEM - The 3rd channel of H field amplifier (on the controller) and the single E field amplifier share the same ADC.... (RED system operators with E field should be familiar with this confusing operation)... which means basically the 'lowest threshold' on either channel (H3 or E1) will be the threshold of the other ,,, you can follow our struggle with this a couple of years ago when E was added to RED... we finally figured it out... at this board: http://www.wxforum.net/index.php?topic=22710.0

If I build a loop should I build the conventional loop antenna with 90° lobes and add a horizontal loop around the outside or inside of the conventional loop antenna? Or would the horizontal loop be a separate antenna?

The horizontal loop would be connected to channel 3.
Michael Lloyd  NE5U
Weimar, TX USA
Stations: 1745
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#8
I started with all three loops together but local conditions mean that 90 degrees between the loops produces useless signals. See post #5 ... I now have seperate vertical loops with a horizontal around one of them.

Starting seperate means you don't have to rebuild if you need to use the null of a loop to reduce local interfernce. If you have the loops fixed at 90 degrees, you can null the interference on one but the other is then aligned for maximum pick up...
Cheers
Dave.

Stations: 1627
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#9
(2017-03-30, 00:57)allsorts Wrote: I started with all three loops together but local conditions mean that 90 degrees between the loops produces useless signals. See post #5 ... I now have seperate vertical loops with a horizontal around one of them.

Starting separate means you don't have to rebuild if you need to use the null of a loop to reduce local interfernce. If you have the loops fixed at 90 degrees, you can null the interference on one but the other is then aligned for maximum pick up...

That makes sense. It's probably easier to build them separately
Michael Lloyd  NE5U
Weimar, TX USA
Stations: 1745
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