In a previous post (http://wp.me/p3TYmc-c6), we discussed strobes for survival. Here is the first comparison, between those of the class ‘micro strobe’. These are the smallest of the ‘strobes’, generally of interest primarily for smaller kits.
Since these are pretty much short range devices, the test was down a dark country road, with no street lights but several porch lights so the darkness was not complete. The length of the road was 3/10 of a mile, so that was the maximum range I tested these at. These should be considered ‘worst case’ conditions, as against a darker background common to wilderness, and with eyes more adapted to the darkness, a significantly larger range should be realized. Still, for comparison purposes between this class of unit, this was adequate.
Here are the candidates:
First up is the smallest, a ‘micro strobe’ from http://www.m4040.com. This has three flashing LEDs, one each red, white and blue. It weighs 1/10 of an ounce and is 1/2 an inch in diameter and about 3/4 of an inch long with the built in clip, and runs on two CR927 button cells. The cost is $2, or less in quantity. The run time is claimed to be 30 hours at full brightness then decreasing brightness for another 18 hours. It is not particularly sturdy and is unlikely to be waterproof; the built in-clip is good for fastening to the edge of clothing, hat brims or small branches. It pretty much is only visible from straight on, and the range I got under the specified test conditions was .1 mile. This is not really enough to be a true signal strobe, but it is small enough, light enough and cheap enough that they would be excellent for marking things at night, and under true survival conditions, might well be enough to be seen by someone who was searching for you. I generally like to have a couple of these in every kit they will fit into. But I also include a better strobe whenever practical.
The next test was the UST SplashFlash, a single AA flashlight/flasher. The flash is actually ‘S-O-S’ which is better than a straight flash. It weighs 1 ounce with the included mini-carbiner; maximum diameter is 7/8 inch and length (not including the carbiner) is 3″. It appears rugged and is rated waterproof to 3 feet, with a flash run time of 16 hours claimed. Turn the lens for steady on (12 hours claimed), turn it off then quickly on again for flash. Cost seems to run in the $10 to $12 range. This has visibility from all directions; it was still visible at .3 miles straight on indicating a bit further range is likely, but only visible at .2 miles from the side. Under wilderness conditions, this would probably be a decent small flashing signal, with adequate battery life, but as a flashlight, I’m unimpressed with the run time. I probably would not include this in any of my survival kits, although I might carry it in my pocket or attach it to some non-survival equipment for everyday use.
The last test subject was the Tag-It signal light, from http://www.survivalmetrics.com for $15 ‘on sale’. This is available in various colors; I tested the white. It is 1″ at the thickest point, 1 1/4″ wide and 2 1/4″ long at the built in clip, and weighs .75 ounces. It appears to be rugged, and is rated as waterproof to an impressive 300′. The claimed battery life is an astounding 250 hours from a battery pack of two CR-2032 batteries. If you can’t find the battery pack, it is possible to use two loose CR-2032 batteries if you are careful when inserting them. By inverting the battery pack, it can be used as a constant light, with a respectable 100 hour claimed run time. Activation is by turning the lens. Straight on, it was still quite visible at .3 miles, so I suspect it might even reach .5 miles under these conditions, and further under wilderness conditions. From the side, the range was disappointing, only a bit over .1 mile. All in all, I was fairly impressed with this unit, and plan to have one attached to the packaging of most of my kits (to an external zipper or D ring, not IN the kit). My thought is that it will be convenient for starting signalling without rummaging through the kit. I plan to do this even on kits which have a ‘real’ strobe in them, due to the excellent run time and ease of attachment.
US Coast Guard requirements for a marine strobe are 8 hour run time, which all of these more than satisfy. The required brightness is ‘.75 candela’, which none of these units are rated in, so it is not known if any of these would meet that specification. For curiosity, I used a UST See Me 2.0 LED strobe under the same conditions, which greatly exceeds USCG requirements. It did not appear substantially brighter than the SplashFlash or Tag-it straight on, although its sideways visibility was much better than those two were when viewed sideways. It is possible that either of these small units might meet the USCG specifications, but I would not risk a Coast Guard inspection without making sure of that. Plus having your marine strobe start automatically if dunked in the water sounds like a really good safety feature.
Once I find a longer test site, I can put the ‘full size’ LED strobes to the test, and finally the Xenon strobes.