Other SOTA sites: SOTAwatch | SOTA Home | Database | Video | Photos | Shop | Mapping | FAQs | Facebook | Contact SOTA

Strikealert Portable Lightning Detector


#1

Posted this short review below on the Bacon Bits Flying Pig QRP newsletter a few years ago. Thought some folks might be interested in this portable lightning detector with the summer thunderstorm season waking up (at least in the northern hemisphere). Small unit about the size of a belt pager. Can be fairly inexpensive depending on where you can find it. Got my last one from Amazon.com.

Mike, N4VBV

First saw it at a SKYWARN refresher class where the NWS instructor had a personal unit he checked frequently. Next day I checked Google and some places had them for up to $99.95 for the same unit.

The unit is the size of a small pager with belt clip and uses one AA battery. It has a row of LEDs across the top labeled “24-40”, “12-24”, “6-12”, and “0-6” along with a green “PWR” light. The two farthest range LEDs are yellow and the two closest ranges are red. The power switch switch can be pressed inboard for another function. It can be set (via slide switch) for silent (lights only) or to beep with the lights, as well as “OFF”. When turned on, the unit performs a battery test, lighting up the LEDs from red to green, stopping at an LED that indicates approximate battery condition, then goes on to normal operation. When it detects a lightning strike, it lights an estimated range LED and beeps according to the lit LED (unless “silent” is selected, in which case only the appropriate LED will illuminate).

As the appropriate LED lights, the unit beeps corresponding to one of the ranges listed above (one beep for the farthest range, increasing to four beeps at the closest range). The LED will stay illuminated for two minutes after the strike. If another strike farther away occurs, the farther range LED will light (with corresponding number of beeps) for two seconds, then the display will revert to the closest strike LED that was originally illuminated (unless the two minutes have expired). If the succeeding strike is closer, then the closer LED will stay illuminated for the two minutes, indicating the closest strike. If the “PWR” slide switch is pressed towards the center of the unit, the LEDs will flash to indicate storm movement. If they flash from green to red the storm is approaching, and indicate storm movement away by flashing red to green. This doesn’t mean the storm is moving directly at/away from you, it may be a glancing approach at an angle as it arrives/departs. If the unit determines the storm is stationary, the LEDs will flash from the center out to each end at the same time. This also indicates the unit can’t determine movement due to insufficient information (not enough strikes to determine movement).

The “PWR” light also functions as an interference indicator. If the green light is flashing the unit is detecting interference. The manual indicates that computer monitors, etc. may cause interference; just move the unit a few feet away. The manual also mentions that it may miss some strikes if the storm is very close, but by then a storm is pretty obvious. In my 2000 Ford Explorer the turn signals (probably the signal relay) and brake lights will cause the unit to indicate close storms. My FT-8100 transceiver on 50W VHF will not trigger the unit, but 5W UHF does. It will not trigger next to my HW-9 transceiver (5 watts)/long wire setup even sitting next to the rig (at least on 40 meters when I was testing by using two wires for a code key). You can guess what the Bug Zapper does to it. So how does it work? Great for what I bought it for.

I spend quite a bit of time outdoors with my 3 yr. old daughter fishing, horseback riding, flying (haven’t tried it in a plane), and generally exploring, so it’s an added safety net. Here in South Carolina the storms blow in or build quickly, and are sometimes hard to see due to haze/tall trees until you hear lots of thunder. The Strikealert gives a little more warning. Also a good reminder around the house to ensure antennas are disconnected. The approaching/departing feature corresponds pretty well with the weather channel. I did use the Bacon Bits Newsletter from the Flying Pigs QRP Club, International August , 2003 five second rule (count seconds between flash and thunder; then divide by 5) to check the closer ranges, and it worked fine, indicated the correct ranges.

I really like leaving it on the “beep” setting to indicate a storm, especially on the hot, humid afternoons here in the South. One case in point - As a few of us were leaving work last Friday, a golfer friend was interested in the Strikealert, so I was giving a demo. It started beeping, indicating an approaching storm. I thought it was just my NOMEX flight suit (the manual does mention that static-prone clothing may trigger it). So we had a laugh and he thought I had gotten taken, as I was starting to wonder myself as the sky we could see was clear with only a few clouds. Forgot all about it until a half hour later when I walked out of a store and the sky was VERY black (had left the unit in the truck). Ten minutes later the rain and hail had visibilities to a couple hundred feet and the lightning was very intense. I think I’ll keep my Strikealert. QRP radio applications: Field work, antenna reminder during storm season, camping, other outdoor (non ham) activities like fishing, boating, etc. Where to get it: a Google search is always good, but I bought mine from Provantage.com for $49.95 plus $5 UPS. Other places had them up to $99.95 (check Amazon.com). More Strikealert details can be found on the web at " www.strikealert.com ". No financial connections with Strikealert.


#2

There are a number of these devices about, more or less a AM transistor radio with a signal strength indicator of some sort.

Otherwise just listen to your H.F radio for the lightning crashes and make estimates from the strength of the static bursts.

73’s, Nick


#3

Interesting stuff indeed.

If you have decent mobile phone and net connection there is the lighting map but this would be handy as small compact and lets you know. Last thing you want is to be up there in middle of a storm.

My first experience of lightening strike was out on me M/C following another gent about 20m apart and it was chucking it down. God almighty flash and hello where’s me mate gone. Found him in the hedge smoking and pulled him out. You could see the burn marks across his back of his denmin jacket on top of his leather jacket and hole in the seat of his M/C the battery well was toasted and the electrics pretty much fried. Pretty much shock up big time but well alive.

HOW MUCH ouch :scream:, hmm small Trans AM radio yes good alternative.

Now surely the biggest danger is build up of static voltage on antenna system. Used to have a very long wire at 25ft high and was 100ft long for SWL my meter i had did 500v even seen that go off the scale before even a storm arrives in place used to live very high on hill to local surroundings. Even set up a spark gap to earth and seen it jump 2cm gap. Scary stuff . Set up a resister between earth and me antenna to stop the build up of static.

karl


#4

I have had one of these for many years (the cheaper “pager” type). It works well and is way better than carrying an AM radio (it is automatic and does far more). I have only once actually acted on its alerts - on the summit of Mellbreak. It was one of my more scary activations.

That being said, I hardly ever remember to take it with me so it’s far from being an essential bit of kit for me.

I should add that I also built my own PIC controlled lighting detector - that worked well too. There is now an IC that does the job:

…I have one of those somewhere too.

Useful reading:

http://www.techlib.com/electronics/lightning.html