You would think detecting lightning would be easy. Each lightning bolt has a staggering amount of power, and, clearly, you can hear the results on any radio. But it is possible to optimize a simple receiver circuit to specifically pick up lightning. That’s exactly what [Wenzeltech] shows in a page with several types of lightning detectors complete with photos and schematics.
Just as with a regular radio, there are multiple ways to get the desired result. The first circuits use transistors. Later versions move on to op amps and even have “storm intensity” meters. The final project uses an ion chamber from a smoke detector. It has the benefit of being very simple, but you know, also slightly radioactive.
You might think you could detect lightning by simply looking out the window. While that’s true, you can, in theory, detect events from far away and also record them easily using any data acquisition system on a PC, scope, or even logic analyzer.
Why? We are sure there’s a good reason, but we’ve never needed one before. These designs look practical and fun to build, and that’s good enough for us.
You can spruce up the output easily. You can also get it all these days, of course, on a chip.
Want to see a couple detectors in action? See
https://www.blitzortung.org/de/live_lightning_maps.php
I have one of these on my roof, had it for years now.
It’s cool to watch the map during a storm.
Nice to see Charles Wenzel still at it. One of the great treasures of the web.
Not that I recommend this, but I have built this once or twice…
https://www.otherpower.com/otherpower_detector.html
I’ve built many lightning detectors over the years.
I find 500kHz stuff is directional (cloud-cloud vs ground strikes) so more than one loopstick needed, and the BW of a simple tank circuit too much so AM radio stations get in the way. So I do not have great results with that. This also makes the Franklin IC AS3935 not very good. It detects splatter from AM radio. Do the math on bandwidth… it false triggers despite all the hoopla.
Research shows that best is VHF- you get extra minutes of warning time which can be critical.
They troll storms with SDR and see what is emitted. In the old days is was TV Ch. 3 that went all weird.
I tried to get one of those AS3935 detectors to work. Adjusting the settings would make it either pick up every little bit of electrical noise in the area or nothing at all.
Lightning detectors are commercially useful. I remember spotting one while XC skiing on a golf course near me.
I have seen it in operation at another HAM friend of mine home location. He had four vertical antennas with vacuum relays attached to each element. One blistery afternoon day standing next to one of the elements I could see a small flash of a static discharge in one of the relays every time a strike of lightening about 15 miles away flashed.
Wow, here’s the name haven’t seen in awhile, “sferics detector” :- ] Looks like an upgraded/revised/improved version of the old school circuit I stumbled across few years ago. Haven’t found the time to try that one, so this weekend projects will probably be the one in the article.
What is that green TO-220? And why aren’t there more of those??
I didn’t want to reply to your comment, obviously. But I guess the comment system still does weird things
The TO-220 must be the “TIP32 or similar” PNP power transistor. All the other transistors are in the “venerable” CA3096 transistor array IC. The text even says “…the transistor in the array can’t handle the current. I added an old green (PNP) GE power transistor to handle the additional current”
Not TO-220, even OLDER than that. I believe the circuit had a tube or two and fancy custom-made VU … pardon … LI meter (Lightning Intensity or something). It was fairly obscure product that never had much of a market and the company that was making it faded after selling like few dozen units.
Obviously, it was not exactly the detector it purported to be, and funny has it, the spare LI meters can still be occasionally found on them ebays. I obtained like 5 or 6 VU/LI meters years back out of curiosity, heavy chunky solid metal cores instead of pressed-powder, etc.
I had a PDF of the web page somewhere, gotta dredge up layers of internet dust particles. I’ll see if I can locate it among the noise.
Clearly Matias and I are not referring to what you’re talking about, as his reply indicates.
Can it also detect Palpatines force lightning?
Any AM radio tuned between stations works very well to detect, doesn’t it?
Yes, you’re absolutely right. You can use any AM receiver with a longwave (LW) or mediumwave (MW) band and a built-in ferrite antenna and tune in between stations (or grid interference).
It’s best to tune in to the longwave band between 150 kHz and 270 kHz.
It can also be a shortwave receiver, but then you’ll need to connect an external antenna (e.g., a 5-10m wire placed in a room by a window) and ground.
The simplest lightning detector, however, is a simple miniature neon lamp, e.g., NE-2 (available on AliExpress, Amazon, Farnell, or eBay), connected between a horizontal wire antenna (5-10m long) placed outdoors above the ground (behind a window is sufficient) and ground (e.g., a thick (10mm) steel rod, 1m long, driven into the ground).
This neon lamp flashes when lightning strikes nearby. WARNING: Experimenting with external antennas during a thunderstorm is dangerous! Think about what you’re doing!
The Province of British Columbia has a network of lightning detectors which are used to direct field resources (e.g. spotter planes) to areas where lightning strikes may have resulted in forest fires.
During the fire season, keeping these sensors (and the fire attack bases that rely on them) online is priority #1. I once had the pleasure of telling a Deputy Minister that his slow internet complaint would have to wait because I was working on a lightning detector ticket.