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Probe your Strobe

Gary Jacek

Dec 11, 2009
Victoria, BC
Years ago on a SISKA visit to our local Rescue Coordination Centre at CFB Esquimalt, I chatted with a former SARTEC about the best ways to make yourself visible to rescuers. His response was to use the VHF/PLB to call for help. When rescuers are spotted in daylight, pop a smoke flare. If it is dark or you expect it to be dark soon, or your hands are getting cold, start up a strobe. Strobes operate for many hours and light up the whole sky in the rescuer’s night vision goggles.

As advised, I purchased strobes and smoke flares.

Years passed.

On this cold winter day I decided it was a good time to inspect gear and replace worn items.
I planned to strip the kit off my much-too-old PFD, inspect and reinstall it on my replacement PFD.
So off came my water supply, knife, tow rig, VHF and PLB. All in good working order.

The final item was my Princeton Tech Strobe which was sewn to the shoulder patch. Yes, still operating when tested.
Off it came, and of course I opened it to inspect the alkaline battery.

It turns out the battery was just starting to ooze. Fortunately, the metal strobe components were not yet affected by the evil ooze.
Tossing the battery, I decided to soak the internal housing (not the cap) of the strobe with white vinegar in order to neutralize the battery residue.

As I poured in the vinegar, it promptly poured right back out the bottom of the waterproof strobe housing.
Hmmm…not good.

Careful inspection of the housing revealed a crack around the unused lanyard attachment point.
The crack is difficult to see, so I have marked it with a red sharpie in one of the photos.

Riding high on my shoulder, the strobe only gets wet when I roll or practice rescues. And of course during the momentary post-paddle, freshwater rinse.
In a real emergency, when I could be in salt water for hours, the strobe would have soon flooded and expired.

Have a good look at your Princeton strobe and all your other gear. Is it ready for another season on and in the water?

I've gone through a couple of strobes. A Princeton Tec and a very expensive ACR. The ACR cracked and started leaking while the Princeton Tec battery oozed. I replaced it with another Princeton Tec.
Your post is an inspiration. I was inspecting the same thing a few weeks ago but I had Zip Tied it to my PFD's patch and didn't want to cut the well-trimmed ties. I have a different model and figured I had to remove it to allow for the required twist - I'll look again. The strobe works - but for how long.

T'were it me, I'd replace the Alkaline battery with Lithium. 1) it will have a far longer shelf life - and hopefully, that's all its life will be - in the OFF position. 2) It will give full power until it's dead. No dwindling.
Good idea Cougarmeat. In my photo gear I have a whack of Ikea lithium cells. (Reputed to be made on the same factory line as Eneloop branded cells) I‘ll swap in one of these for now.
Do you have a recommended permanent lithium cell?
I have a whack of Ikea lithium cells. (Reputed to be made on the same factory line as Eneloop branded cells)

Eneloops are NiMH, not lithium, and I suspect the IKEA ones are as well. I find they are always dicey in electronics because of the lower voltage (1.2) vs. alkaline (1.5). The device very soon declares "low battery". The disposable lithium batteries are 1.5v and are recommended as cougar says, but I've no experience with them.
The 'older' strobes (like my Princeton with it's unreliable non-intuitive 'loosen' twist-to-turn-on design, and the ACR I had even longer ago) used a Xenon tube to produce a very bright short-duration flash - a true 'strobe'. @Gary Jacek - your damaged strobe is this design?

The newer ones all seem to be LED based (like the 'pretend strobes' on some VHF radios?). The ACR version is touted as having a 'very bright' 40 lumen output. (A typical single AA LED flashlight I own has 200 lumen output).

I wonder which type of strobe the SARTEC was recommending?

I've also read comments that the LED 'strobes' are not visible from 360 degrees and above. Is this correct?

An LED strobe is far far better than nothing, but I wonder about the 'progress' we are seeing here.....
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I would not use "rechargeable" batteries in anything important because 1. They have a relatively poor shelf life. 2. Are not 1.5 volts. 3. sometimes they are a little larger in diameter. 4. AA's are available in most grocery stores.

Point one - Admittedly, they better with each technical advance - addresses how quickly the rechargeable cell diminishes on the shelf. Sure, the spec might say, "maintains 80% charge after 6 months." But for something like a strobe, it might not be used for years. That "always ready" comment in the marketing text might mean it is "always ready" to be recharged. :)

Point two - I believe this was covered before. The difference between 1.5 and 1.2 might not seem like much. But if you needed two AA's that would be 3V vs 2.4V or 20% reduction out of the gate. Note that Lithium usually starts out higher than 1.5V Also, though the chemistry has removed the memory effect - where the battery should be mostly discharged before recharging. They still have a limited number of "recharges" in their lifetime.

Point three - This isn't so strong, but in the past, I sort of recall not being able to fit the rechargeable in a space/holder that was precisely sized for a standard AA.

Point four - I don't know if I can make this claim with Lithium, but AA's are easily found around here in Fred Meyers (Kroger) and Safeway. Lithium used to be expensive but these days they are less than a dollar more than Alkaline - worth the difference to me. I pick what brand is there - I think usually Energizer. At that point - with a 10+ shelf life (advertised), I'm not looking for "the best".

When rechargeables first came out, I thought they would be the cat's meow and bought a bunch. I soon found out my electronic devices wouldn't work with the reduced voltage. Then I found out that when I wanted to use them, they needed to be recharged first - because they've been on the shelf.

The technology gets better each year, but for me, Lithium is the way to go. The downside is also the plus side. Your device - if it has a battery status indicator - might show a full battery when the Lithium is actually near empty. That's why we carry spares.
I’ll be on the lookout for single use lithium AAs.
Also in my experience, Duracell alkaline AAs of recent manufacture tend to leak often, whereas those that expired in 2013, don’t. Perhaps something changed?
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