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electricflyer
05-30-2016, 11:05 PM
I bought a lightning detector from Amazon a couple days ago. I have Prime so I got it in 2 days. Delivered today, a holiday. Anyway it is a handheld/pocket detector primarily designed for hikers to use when out in the open. It is an Acurite model 02020 and uses 2 AAA batteries. It will easily fit in your pocket or clip to a belt. The literature says it will detect lightning as far away as 25 miles (depending on terrain). I've had it on tonight and it has alerted 3 times. The strikes were far enough away it couldn't measure the distance. There was a strong storm that went through 2 counties north of Atlanta which would have put the storms about 20-25 miles from my location so I guess I works. The cost was about $30 including tax. Of course delivery was included with Prime membership. I also get lightning alerts from the weather service on my smartphone.






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N3LYT
05-31-2016, 08:40 AM
Here is any other lighting test it's part of a huge world wide detection system very accurate with nice maps lightingmaps.org/realtime.

NN5I
05-31-2016, 05:03 PM
Me, I can generally detect lightning. See, there's this big bright flash, and a loud noise that even I can hear ...

Radio
05-31-2016, 05:33 PM
Does being inside the trailer affect the distance measurement? Thinking faraday shielding effect.

electricflyer
05-31-2016, 10:48 PM
Does being inside the trailer affect the distance measurement? Thinking faraday shielding effect.

Haven't had it on the road yet. There is an indoor setting which it says makes it less sensitive to interference like microwaves, cell phones, electric motors, PC's, and hard drive motors. I don't think there is any shielding effect since I don't believe it is sensing RF. I do have aluminum walls for my TT so we will see. I think I have seen lightning sensing modules for Ardunio micro controllers, so you could make your own detector with a little "C" programming experience for around $10.

NN5I
06-01-2016, 07:20 AM
It is certainly sensing RF. Lightning detectors have been around for a long time.

They detect RF and distinguish (or attempt to distinguish) lightning-generated RF by its risetime and its frequency distribution (which are not, by the way, independent variables). They estimate distance mostly by amplitude, so one would expect anything that reduces the signal strength (such as the metal body of a trailer or motor home) to cause them to estimate the distance as greater than it is. Other effects (such as the difference in polarization of the RF depending on whether it's cloud-to-cloud or cloud-to-ground) may cause the detector to think the lightning is closer than it is.

In order to indicate the direction of the lightning from the detector, the detector must use some configuration of multiple antennas. With only one antenna, it can estimate distance but not direction.

The first lightning detector (invented, if I remember correctly, late in the 19th century) was also the first radio receiver.

N3LYT
06-01-2016, 08:14 AM
Does being inside the trailer affect the distance measurement? Thinking faraday shielding effect.

The camp ground I work for part time last year took a hit between two trees danced across one campers roof took out just about all of the electronics in both campers over $4,000 for each camper. One camper was occupied they were unhurt that's the one with the scorched roof! not sure if they will ever camp again there was no doubt about how close the lighting was with out a detector!

N3LYT
06-01-2016, 08:27 AM
Google Franklin bells. Old Ben made one a long time ago.

NN5I
06-01-2016, 10:11 AM
Google Franklin bells. Old Ben made one a long time ago.

Cool. I had never heard of Franklin bells. An interesting read.

It's certainly a lightning detector, too, although I guess it will detect only hits -- no distant lightning.

It will also detect an atmospheric potential gradient, even in the absence of lightning. Such a gradient nearly always exists, but it's stronger when clouds are present -- especially clouds that grow vertically, like cumulonimbus.

I didn't know any of this (except the part about clouds and electric gradients) until you set me reading, LYT. Thanks!

N3LYT
06-01-2016, 07:22 PM
Actually the bells are pretty good I have no data but they will ring when a storm is a fair ways off I got a fair jolt once disconnecting antennas when the storms were a good 6-8 miles away! I don't do that any more.

NN5I
06-01-2016, 09:40 PM
Actually the bells are pretty good I have no data but they will ring when a storm is a fair ways off I got a fair jolt once disconnecting antennas when the storms were a good 6-8 miles away! I don't do that any more.

Yah, in that case they're not detecting lightning -- they're detecting the gradient.