Topic: Blitzi Baby Red Screamin!

[dfroula]

Yes, the first stations are the ones used in the calculations. The station numbers are also sorted by time stamp of detection in ascending order.

This suggests that it's always the more distant stations (higher time stamp stations at end of list) that are removed from the calculations if the server decides to eliminate one or more stations.

Don

[DaleReid]

My apologies to those who are up and running and may not appreciate how hard it is for us waiting to participate to sit on our hands.

The kit I should be getting will be a new, red, kit.

Can those with these tell me if this interferance issue is something that is auto clearing?  That is, lets say my old maple gets zapped by a bolt and the Red says, too close, I'm shutting down.  Does the detector wait a few minutes, then clear itself and start sniffing again?  Or, does the local operator have to trudge out to push the reset button?  If it is auto correcting, how long does it take itself off line?

I'm about to hit Menards to get the foam board and dig through the junk boxes to get the wire needed, ans so on, this weekend.  Got to do something other than sit on my hands waiting for the kit.  I assume good old wire works well, like stripped phone wire or some other stuff, if I have it?  And eight turns sounds a lot better than 54 turns if I can do the reduced number.  If one makes a reduced number of turns will this affect the inductance figures, and also depending upon the gauge of the wire, affect the resistance so as to alter the resonance?  I'd rather ask and seem dumb rather than have to redo the project because I was afraid to ask about something I'm not up to speed on.  So thanks for any advice.  Dale

[dfroula]

The Red unit goes into and out of interference mode on it's own. I believe there is a "burst mode" (saw it activate this morning on the web interface) that shuts down momentarily on closer multiple-strike bursts. There is a longer term interference that will shut down the station for a predetermined set of time before returning to normal. This is used for high average counts rather than bursts.

Shut down simply means the station stops sending data to the server. An LED and audible alarm indicate the interference mode is active. The status web page has a list of total detections and good detections. Good detections are signals that exceed the threshold when not in interference mode. When in interference mode, the unit is still counting strikes and incrementing the total strike counter. It will not increment the good strike counter if in interference mode.

I've built the 52 turn flat panels. I really like the added gain. I have to set the gain quite low, but there is definitely adjusting range a few steps below my optimal settings. My theory is it's better to have better antenna gain with higher SNR, then try to make up for a low-gain antenna by boosting power.

Resonance is not an issue, as with a traditional antenna. The lightning impulse is broadband. For the best detectable signal waveform, any resonance in VLF is to be avoided. Most loops have a self-resonance way above VLF. Ferrites tend to have lower self resonance which can affect the waveform if not constructed properly. No capacitor should be used to try to tune the loop.

My apologies to those who are up and running and may not appreciate how hard it is for us waiting to participate to sit on our hands.

The kit I should be getting will be a new, red, kit.

Can those with these tell me if this interferance issue is something that is auto clearing?  That is, lets say my old maple gets zapped by a bolt and the Red says, too close, I'm shutting down.  Does the detector wait a few minutes, then clear itself and start sniffing again?  Or, does the local operator have to trudge out to push the reset button?  If it is auto correcting, how long does it take itself off line?

I'm about to hit Menards to get the foam board and dig through the junk boxes to get the wire needed, ans so on, this weekend.  Got to do something other than sit on my hands waiting for the kit.  I assume good old wire works well, like stripped phone wire or some other stuff, if I have it?  And eight turns sounds a lot better than 54 turns if I can do the reduced number.  If one makes a reduced number of turns will this affect the inductance figures, and also depending upon the gauge of the wire, affect the resistance so as to alter the resonance?  I'd rather ask and seem dumb rather than have to redo the project because I was afraid to ask about something I'm not up to speed on.  So thanks for any advice.  Dale

[DaleReid]

dfroula:

Thanks for the additional info.  I'm learning!

One more item that came to mind.  Is the preamp pretty well designed, so that a really close strike won't wipe it out?

I remember some time ago that a friend transmitted on his supposed 5 watt CB next to a buddy's parked car and fried his front end.

I know a couple mobile hams who try to stay a couple miles apart when travelling together to keep from interferring with their rigs with a super strong local signal, and they seem to know their stuff so I assume there is something to this.

Having been holding a 30' piece of aluminum pipe and having a cloud to ground strike about 3/4 of a mile from me and feeling it jolt me pretty good, (single turn antenna?) I do know from practical experience the possible voltages that a strike can induce.

Thanks again.  Dale

[dfroula]

Yikes....the "Efficiency" number as a measure of station performance just got more complicated:

The Blitzortung web site now has THREE efficiency ratings for short, medium, and long range detections. According to Egon, these ratings are simply the strike ratios or the ratio of detected strikes including the station of interest to the total number of strikes detected by the system. Ratios are now calculated separately for each distance range.

The lighningmaps.org efficiency rating multiplies the overall strike ratio times the signal ratio and takes the square root of the product. Signal ratio is the ratio of the station detected signal count to the total number of system detected strikes.

Egon considers the lighningmaps.org efficiency rating most applicable as an overall performance indicator for tuning antennas and gain.

I like to look at the lightningmaps.org efficiency rating over a 24 hour period or longer to get meaningful results. Short term variations can be seen in the hourly stats due the distribution of lightning in the region.

Confused yet? 

Don