McE2S question

[Geode]

Hello,

I am considering getting this tailcap, but was curious if after putting it on the L4, the low setting made a "whining" noise like that associated with the A2 and L2.

Any comments from McE2S users? Thanks.

 

[Haesslich]

The L2 and A2 use a regulated low mode, IIRC, which is why you get the whine. The Mc2ES tailcap only puts in a resistor into the cap, so that the low mode engages the resistor to decrease the current running to the light - therefore, no opportunity for a whine to be made since there's no circuitry outside of ONE resistor.

 

[Geode]

Crikey - why doesn't Surefire do that too? Good explanation.

 

[McGizmo]

The A2 is not a regulated low; simply a resistored circuit for the 5 mm LED's while the incan circuit has cut off power to the incan. I believe the whining comes from the converter and not the tailcap. I attribute any lack of whine in the L4 to some difference in its circuitry. /ubbthreads/images/graemlins/icon3.gif

The SF two stage switch used on the L1, L2 and A2 is also a resistored switch with a resistance of 10 ohms. In electronic function, it is really no different than the McE2S.

 

[Darell]

Bit o'confusion here.

First off, as Don mentions, the A2 isn't regulated on "low." It also doesn't whine. At least mine don't! The circuits that seem to "whine" are the low circuits of the L1 and L2. These low circuits are *regulated*. The high circuits don't seem to whine. The Aleph "low" forces the chosen circuit out of regulation, and does not make it whine. These are different animals!

Don menttions that the L1, L2 and A2 have a resistored switch - but they don't all work the same! In the A2, it works similar to the Aleph where the LEDs are driven through the resistor for unregulated output. With the L-series, adding or removing the resistor through the use of the tailcap, chooses which circuit to run in *regulation*.

Did I just confuse it more?

 

[McGizmo]

Darell,
The current version L1 does NOT have a regulated low level, it works very much as the McE2S does on the boost drivers, like the BB and NexGen. The L2 is the first light, to my knowledge with two independent drivers; one for low and one for high.

 

[Geode]

Hi Darrel (and gang) - my A2 had a distinct squeal to it. Very high pitched, but definitely there when in low light mode. Thanks for your educate answers.

 

[Flatscan]

A2 noise

I don't think my A2 whines, but I don't have it right here to check. My BB750 sandwich in MiniMag with 2-stage Kroll doesn't make any noise on low, but makes a definite buzzing at the converter on high. My BB400 E-pill on 2AA (no 2-stage) buzzed and flickered until I took the 123 extender off, cleaned the threads, and put it back on as tight as I could. My guess is that residual resistance/intermittent connection resulting from poor maintenance, damage (Kroll), or poor initial construction (E-pill) causes the converter to make a noise.

I would not expect a McE2S to cause noise when added to an L4.

Edited to add:
I fixed the problem with the BB750 sandwich. I swapped it out to test a different sandwich, and I noticed that the collar that I had been using as a head stop had shifted a little. The optic was pushing the sandwich down, enough to interfere with the ground path, but not enough to turn it completely off.

 

[Kiessling]

Could be a bad contact causing some "arcing" and thus the noise. Experienced this in a PM6 / McModule some time ago, and cleaning the contacts solved the problem.
This could be possibly hazardeous due to heat delevoping where the arcing takres place.
bernhard