A2 - low medium and high, wtf?

jayhackett03

Enlightened
Joined
Oct 14, 2006
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369
Location
Kansas
i just picked up my aviator and hit the button, it turned on a low output incan.

by applying different pressure, i can make it go from low, medium, then high. medium and high are incans.

are my batteries just low or what?
 

Daniel_sk

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May 29, 2006
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Slovakia
It doesn't need to be the battery, here is what Js writes in his long A2 review:

....And for those of you who have often wondered what is going on when your A2 appears to have three levels (LED, low incan, high incan) depending on how the switch is pushed or on the luck of the draw, here is what is going on: there is some extra resistance in the circuit. (Assuming you have fresh full batteries installed, of course--low batteries will exhibit this low incan mode even if all contacts are clean and everything is in working order) The extra resistance could be due to contact resistance in the LOTC floating contacts or in the battery stack or somewhere else. Or due to a broken spring contact. But somewhere there is extra resistance—just small enough so that the LVR sees enough voltage to allow it to turn on but too much to keep it on. So it turns on and starts to draw high current through the lamp, which causes a larger voltage drop across the switch and contact resistance, which lowers the LVR input voltage, which causes it to turn off; and the same thing happens over and over again. Sometimes you push hard enough, or the position of the floating LOTC contact on the end of the body tube is such that there is a small enough resistance to run the incan in regulation. But other times, there is too much resistance, and you put the LVR into an equivocating state of confusion about whether it should be on or off, resulting in a sort of in-between state, and thus the so-called "low-incan" level. If you remove the switch and simply short circuit the battery stack negative to the body tube, I bet you will find (in these situations) that it works fine. This indicates the need to clean the contacts inside the switch with a soft cotton pipe cleaner, and the butt end of the body of the light with a cloth or paper towel.

You can read the whole review here:
https://www.candlepowerforums.com/threads/107943
 

Bravo25

Flashlight Enthusiast
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Nov 17, 2003
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1,129
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Kansas, USA
The one I had turned out to be defective tail switch. Several nights of playing Surefire Lego finaly revealed this, and a quick phone call to them got another in the mail.
 

Illum

Flashaholic
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Apr 29, 2006
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Central Florida, USA
before you toss the defective tailcap, take the rubber retention ring off with needle nosed pliers, the rubber boot wears with use you know ;)

if you want you can crack it open and salvage the 10 ohm resistor if you want...its a surprisingly simple idea for the low output selection
 

Grox

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Joined
May 31, 2005
Messages
1,214
Location
Melbourne, Australia
What brand are you using?

If you're not using name brand (surefire, energizer, sanyo, rayovac) I'm not surprised. The A2, more than just about any other light, is picky with its batteries.

From the resolution you described above, it sounds like the batteries are the source of your problems.
 
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