StrikeAlert, is a small and affordable lightning detector that provides an early warning of approaching lightning strikes from as far away as 64 Km and lets you know if the storm is coming your way. An audible alarm sounds when there's a strike and a corresponding LED light illuminates accordingly at lightning distances of 40-64 km, 20-40 km, 10-20 km and within 10 km. The detector is housed in a small pager-like casing that can be clipped on a belt loop and runs on a single AA battery. It's perfect for outdoor sporting events and activities.
The power switch has three positions: On, Off and On with tone. The switch may also be depressed to indicate the direction of storm movement
When first turned on, StrikeAlert performs a battery test. The LEDs will indicate the battery level, with each LED indicating about 20 hours of operation. The LEDs will light up, beginning with the red LED and leading up to the current battery level. The current battery level will be the final LED to light and will remain lit for two seconds. StrikeAlert will then begin its normal operation.
During normal operation, the green LED will be on continuously to indicate StrikeAlert is monitoring for lightning strikes. If the green LED is blinking, StrikeAlert is in the presence of interference.
Detecting Lightning Strikes
When a lightning strike is detected, StrikeAlert will light the appropriate LED indicating the distance of the strike This LED will remain lit for two minutes- unless another strike occurs during that time. If a more recent strike is further away, the LED indicating this distance will light for two seconds, and then return to complete the two minutes from the nearest strike. If a more recent strike is nearer, it will replace the previous LED reading. This LED indicator will be held for two minutes. This allows the user to see all the lightning activity within a 70 km range, giving clearer visibility to the nearest strike in the last two minutes. If the power switch is in the "On with Tone" position, StrikeAlert will also generate tone(s) indicating the distance of the strike along with lighting the appropriate LED. This allows you to determine the storm's activity without having to monitor the LEDs.
Strike Alert uses a trend of strike distances over the last five minutes to determine if a storm is approaching or departing. By depressing the power switch, the LED will change to one of three patterns:
If the LED cycles from green to red, the storm is approaching.
If the LED cycles from red to green, the storm is departing.
If the LED cycles from the center LED to the outside LEDs, the storm is stationary or there's not enough data to determine the direction of the storm.
Direction cannot be determined if there has not been enough strikes to identify a trend or StrikeAlert has not been running long enough. Approximately five minutes is needed in the presence of lightning strikes to determine direction.
StrikeAlert is designed to be used outdoors. While StrikeAlert will work indoors, its ability to detect lightning strikes can be affected by common sources of electromagnetic emissions, such as:
CRTs - (televisions or computer monitors)
Motors and engines
High-powered electronics equipment
Moving StrikeAlert a safe distance away from these devices (usually a few feet) should allow the detector to return to normal operation. This will be indicated by the green LED remaining constantly lit.