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We heard three/four strikes near us, but no indication of those on map.
( During last two T.S that passed through today )
Intensity of strikes too low or no rcvr site near enough to our location?

73,

Tom - WØTDH
(2014-07-23, 21:36)WØTDH Wrote: [ -> ]We heard three/four strikes near us, but no indication of those on map.
( During last two T.S that passed through today )
Intensity of strikes too low or no rcvr site near enough to our location?

73,

Tom - WØTDH

Between the DC region and Florida, there is indeed a "gap" without stations. Typically, to detect strikes in NC would probably require the participation of (at the closest) some of the DC region stations, Florida stations, and Kentucky stations. So lower-intensity strikes might get missed, anyway, due to the distance...and if enough of the surrounding stations are in interference mode due to storms in their immediate vicinity, stations even farther away would need to do the detecting. It's a situation higher density of stations will help quite a bit.

It's also possible that the strikes were cloud-to-cloud, which the Blitzortung system (like most lightning detection networks) filters out.
Hello, I'm a new user in this forum Smile
I live in Tromsø in northern part of Norway. Normaly we do not have much lightning here. But last year we had a few days. And this year it has been lighting strikes many times through the summer. We have had especially hot weather thats not normal for this region, so that is the reason for all those lightining strikes.
I first discovered this site when a newspaper posted a picture of the map when the bad weather was coming up from the south in the country. And I have visited this site regualary since. It seems that none of the strikes in the northern part of norway is detected at all. I know there is no detectors here, but it seems that they have a pretty good range? I see detectors in northern Finnland detecting strikes in Germany and Poland...
Will the high mountains in my region interfere with the detections from far away? I see the closest detector is in Trondheim (in middle of Norway) and the ones in northern Finland.

Would it help for the rest of the northern part of Scandinavia if I got an detector here?
Is there special requriements besides power for the electronics and internetconnection that is required for this to work?
Hello,

Lightnings in your area are not detected because the coverage is not important enough. You can have some explanations there: http://www.lightningmaps.org/extra/cover...D=1&bouser

Every participant is welcome but maybe that in your region we will need more than only one detector...

There is no particular needs more than a power supply and internet. Avoid installation near noisy electric equipments.
(2014-08-06, 18:08)F0NIX Wrote: [ -> ]Hello, I'm a new user in this forum Smile
I live in Tromsø in northern part of Norway. Normaly we do not have much lightning here. But last year we had a few days. And this year it has been lighting strikes many times through the summer. We have had especially hot weather thats not normal for this region, so that is the reason for all those lightining strikes.
I first discovered this site when a newspaper posted a picture of the map when the bad weather was coming up from the south in the country. And I have visited this site regualary since. It seems that none of the strikes in the northern part of norway is detected at all. I know there is no detectors here, but it seems that they have a pretty good range? I see detectors in northern Finnland detecting strikes in Germany and Poland...
Will the high mountains in my region interfere with the detections from far away? I see the closest detector is in Trondheim (in middle of Norway) and the ones in northern Finland.

Would it help for the rest of the northern part of Scandinavia if I got an detector here?
Is there special requriements besides power for the electronics and internetconnection that is required for this to work?

That's because YOU were not participating, or you had seen much more. Smile
There should actually just one or two more stations in your area at a reasonable coverage
(2014-08-07, 00:03)RichoAnd Wrote: [ -> ]That's because YOU were not participating, or you had seen much more. Smile
There should actually just one or two more stations in your area at a reasonable coverage
Well, DelandeC said the area was not imporant enough... so maybe there is no need for coverage up here?
"Important Enough" might simply be a translation artifact... not to put words in Delande's mouth, but perhaps he meant "dense"... not enough stations...

Mike
Yes Mike that's right.

Sorry, I do my best Blush
Quote:"Important Enough" might simply be a translation artifact... not to put words in Delande's mouth, but perhaps he meant "dense"... not enough stations...
(2014-08-07, 16:36)DelandeC Wrote: [ -> ]Yes Mike that's right.

Sorry, I do my best Blush
I'm actually amazed at how well folks can translate multiple languages into one common.... strange things will happen... we all just do our best Big Grin if you're bored, get Google translate, enter something in English, translate it to, say German... Then translate the German back to English. Repeat it several times. The final result is liable to start a war... .Lightning
(2014-08-07, 17:01)Cutty Wrote: [ -> ]
Quote:"Important Enough" might simply be a translation artifact... not to put words in Delande's mouth, but perhaps he meant "dense"... not enough stations...
(2014-08-07, 16:36)DelandeC Wrote: [ -> ]Yes Mike that's right.

Sorry, I do my best Blush
I'm actually amazed at how well folks can translate multiple languages into one common.... strange things will happen... we all just do our best Big Grin if you're bored, get Google translate, enter something in English, translate it to, say German... Then translate the German back to English. Repeat it several times. The final result is liable to start a war... .Lightning

Those of us who have enough difficulty speaking one language are just glad most of this board is in English! Big Grin
It sure is a lot of lightning strikes in the region this year. Here is a image from SINTEF, registered strikes between 02:00 (local time) 06.0814 and 02:00 at 07.08.2014.
http://gfx.nrk.no//YpiNjWcKQFxrLxxRImO05...yIZ0bmZ8Hw
They dont say if it is ground-to-cloud or cloud-to-cloud strikes. But there are different types of icons, they maybe indicates diffrent types of strikes.
(I found the image here: http://www.nrk.no/nordnytt/magnus-fanget...1.11867914)
(2014-07-24, 01:51)Jonathan.Williams Wrote: [ -> ]Between the DC region and Florida, there is indeed a "gap" without stations. Typically, to detect strikes in NC would probably require the participation of (at the closest) some of the DC region stations, Florida stations, and Kentucky stations.

Kit on order, and antenna constructed already..... As soon as it arrives, big gap between DC and Florida will be plugged in Wilmington, NC!
https://www.google.com/maps/place/Villag...aa46b0d94a
Just ordered a kit. Before the snow flies hopefully a lot sooner, should have a new station in Worcester Vermont USA to plug in major gaps in southern Canada and the Northeast in general. Elected to go with more sensitive electric field without more urban noise ratios hoping to add to North Atlantic Ocean lightning that is so active in the winter southeast of New England over the NW. head wall waters of the Gulf stream. There might be another in my region as well. More the merrier better accuracy better flash density. Always amazed to see the Maui station detect so long range. Too bad we have so little in hits near the Inter-tropical-covergence-zone (ITCZ) because storms are blazing away 24/7/365
(2014-08-28, 01:50)BobW Wrote: [ -> ]
(2014-07-24, 01:51)Jonathan.Williams Wrote: [ -> ]Between the DC region and Florida, there is indeed a "gap" without stations. Typically, to detect strikes in NC would probably require the participation of (at the closest) some of the DC region stations, Florida stations, and Kentucky stations.

Kit on order, and antenna constructed already..... As soon as it arrives, big gap between DC and Florida will be plugged in Wilmington, NC!
https://www.google.com/maps/place/Villag...aa46b0d94a

I did some testing of my antenna, and my location to see what I was in for interference wise...
Results look promising. Output of loops was fed to an ADC running at 40 khz. Termination was 600 ohms vs. the 2.2 k on the real amplifier. Of course the resolution on the real controller will be much higher, the waveforms look very similar, and you can see the differences in phase and amplitude in strikes of varying distances and directions. Null between the loops looks good, which accounts for the major differences in levels between strikes.

Now if that controller kit would just arrive......Big Grin

[attachment=1352][attachment=1353][attachment=1354][attachment=1355]
(2014-08-29, 14:14)BobW Wrote: [ -> ]
(2014-08-28, 01:50)BobW Wrote: [ -> ]
(2014-07-24, 01:51)Jonathan.Williams Wrote: [ -> ]Between the DC region and Florida, there is indeed a "gap" without stations. Typically, to detect strikes in NC would probably require the participation of (at the closest) some of the DC region stations, Florida stations, and Kentucky stations.

Kit on order, and antenna constructed already..... As soon as it arrives, big gap between DC and Florida will be plugged in Wilmington, NC!
https://www.google.com/maps/place/Villag...aa46b0d94a

I did some testing of my antenna, and my location to see what I was in for interference wise...
Results look promising. Output of loops was fed to an ADC running at 40 khz. Termination was 600 ohms vs. the 2.2 k on the real amplifier. Of course the resolution on the real controller will be much higher, the waveforms look very similar, and you can see the differences in phase and amplitude in strikes of varying distances and directions. Null between the loops looks good, which accounts for the major differences in levels between strikes.

Now if that controller kit would just arrive......Big Grin

Hard to say for sure, but those look like nice, low noise environment plots Smile
That's with the antenna on my porch about 10 feet away from my computer, router, TV not much further. 23 kv single phase power line 30 feet off the ground 30 feet away horizontally makes about 200 mv of AC on the loops to ground. Not much magnetic influence from any of that though. Did a digital 1 k high pass to remove what little was encoded by the ADC. Filter that is on amp board should do the same.

Antenna will be about 70 feet away from house when installed.
(2014-08-29, 17:10)BobW Wrote: [ -> ]That's with the antenna on my porch about 10 feet away from my computer, router, TV not much further. 23 kv single phase power line 30 feet off the ground 30 feet away horizontally makes about 200 mv of AC on the loops to ground. Not much magnetic influence from any of that though. Did a digital 1 k high pass to remove what little was encoded by the ADC. Filter that is on amp board should do the same.

Antenna will be about 70 feet away from house when installed.

BobW, it looks like you are ready to go... Big Grin

What kit did you order? Was it the H-field, E-field or both of them? You seem to be one who is quit technically knowledgeable; however, please do not attempt to make any circuit changes to any of the boards. The network algorithms have been set up to expect inputs from identical stations reporting data. Any changes to the circuitry would most likely alter the input signals from any station that is not standard and thus, would confuse and/or invalidate the inputs.

If you haven't already, check-out the WXFORUM forum that has a complete board on Blitzortung along with step-by-step instructions that will guide you through the assembly process. There are also many posts that will assist in troubleshooting. Taht forum can be found at WXFORUM.
(2014-08-29, 18:11)W3DRM Wrote: [ -> ]What kit did you order? Was it the H-field, E-field or both of them? You seem to be one who is quit technically knowledgeable; however, please do not attempt to make any circuit changes to any of the boards. The network algorithms have been set up to expect inputs from identical stations reporting data. Any changes to the circuitry would most likely alter the input signals from any station that is not standard and thus, would confuse and/or invalidate the inputs.

H-field. Probably too noisy here for E-field.
As far as any board changes.... Nope. The things I have in mind have to do with the antennas, and getting the signals from them into the amplifier unmolested. The amp and controller will either like what it's getting, or not.

I've got years of experience with RF, carrier, and high voltage environments, and getting small signals long distances on copper with no introduced noise.
(2014-08-29, 19:10)BobW Wrote: [ -> ]I've got years of experience with RF, carrier, and high voltage environments, and getting small signals long distances on copper with no introduced noise.

If you mount the amplifier close to the antennas (as it's been designed), you don't need to be concerned greatly about the connection from the antenna to the amp, as it's physically quite short.
H field antennas connect with very short leads directly to amplifier... amp to controller with shielded CAT5e/6 cable. This should be as short as possible,...<25-30' say) not about noise... but about signal delay.... anything introducing extra delay or shape/frequency distortion isn't cool. H field can stay inside, if noise environment friendly. Slightly wider BP then E field ...<150kHz
E field probe... preamp connects directly to probe, view it as single unit. Connects with shielded coax of virtually any length to amplifier, which should connect with shortest possible (1ft?) Shielded CAt5E/6 to the controller. E probe/preamp mounts outside, several feet above ground, away from structures, trees, noise sources... . Coax characteristics is critical part of the filtering for the E system. <50kHz

What type of noise do you have that won't bother H field, but would mess with E field???? Remember, we're not much interested in anything above 50kHz, and most concerned with 5-30Khz (5-20)....