List Lights that use PWM

jon_slider

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List Lights that use PWM or Constant Current that fluctuates

If you Believe a light uses PWM (please include a photo or a link if disputed) that can be detected by waving, a camera, or oscilloscope, even if YOU dont notice it in use, feel free to add to the list. This post is not intended to discuss whether PWM is bad, good, or fast enough not to be noticed. It is ONLY about whether the circuit uses pulses.

The following lights use Pulse Width Modulation: (please add any others you know of)

Astrolux S1
Astrolux A01 Copper Old Lumens edition Nov. 2016, earlier Jan 2015 models were NoPWM
Astrolux K01 Copper
BLF D80
Convoy S2
Emisar D4
Eoslamp SP11-S
Fenix PD40 and LD05
47 mini mkII
Led Lenser NEO headlamp
Prometheus Beta Copper

Eagletac D25 (disputed) reported: here D25A Ti also here and here D25LC2 and here D25AAA, and here #65
Maratac AAA Rev 3 (PWM ended approximately with Oct 2015 batch)
Maratac AA Rev 4
Lumintop Tool AA
Jaxman E2
Klarus XT11
Liteflux LF2XT
Lumintop Tool (PWM ended approximately with Oct 2015 batch)
Lumapower LM21
HDS and another link and a pic
Jetbeam Jet-U AAA note there is a newer version that only has PWM on 10440 according to this
JetBeam RRT01 Constant Current that resemble PWM in photos
McGizmo Haiku (link shows 5 seconds of pre 2013 slow PWM on video). this post confirms the 2017 Haiku still has PWM. Here is a photo of the post 2012 faster PWM
And this one confirms the 3s revision of 2012 still uses PWM
Malkoff MDC AA 3 mode, see photo and photo
Malkoff Wildcat
Manker LAD (Constant current with a feedback loop)
MecArmy PT60
Muyshondt Aeon Mk3
Muyshondt Beagle MKI
Nitecore Tip (disputed)
Nitecore NU20
Olight I3S XPL 180 lumen brass model
Olight S Mini
Olight S2a, on Moonlight #1
PflexPro dropins
Preon
Preon gen 2 series see photo
Nitecore Tube
ReyLight Pineapple pwm photo
ReyLight Ti Lan
SGN3
Streamlight ProTac HL 3
Surefire Sidekick
Tank0007 E09
ThorFire TK4A
Thrunite TH20
Thorfire TG06S
Trustfire TR-3T6
Ultratac K18
Zebralight SC5 (controversial) selfbuilt says it has noPwm, he says same about Eagletac. Zebra scan lines in a photo, in this post #74
Zebralight SC52, pic here

Part of the PWM detection controversy is semantics. Some systems use a sort of hybrid PWM plus minimum current control, eg Eagletac, Zebralight and HDS, use pulses that dont drop all the way to zero, imo they are still pulses.. others disagree, because the strict definition of PWM is that it pulses on and then all the way off.

In my case, a light that has PWM, Pulses, Waves, Flicker, or other fluctuations, can affect my cameraphone images, so I include lights that have one of those characteristics. Make your own judgements about the interpretation, and your application for a light.

A note on technical definitions of PWM and Constant Current:
these are HYBRID drive lights that use Pulses that do not drop to Zero:
Eagletac, HDS, Zebralight, and Nitecore Tip though they are technically NoPWM lights, they are NOT Constant Current because they use PULSES that do not drop to Zero, so cannot be called PWM by the strict definition, but ALSO cannot be called CONSTANT Current, by definition either


#13
Selfbuilt reserves the term "PWM" for drivers that rapidly cycle power between 0 and max. Modern drivers, however, such as the one found in the BLF A6 and BLF Kronos X6 use PWM in a more rational way. They cycle between max and a non-zero output level. On the oscilloscope this results in a ripple that selfbuilt, at least to-date, has not called PWM.

I do not know much about the Eagletac D25A, so I cannot say whether this has anything to do with the reports of PWM on it. I have, however, seen convincing photos posted by CPF member reppans.
quote_icon.png
Originally Posted by reppans

Selfbuilt did not test the D25A, which is all I own. The D25A only uses PWM on a couple of modes (and it's the fastest I've ever photographed), and moonlight has slow PWM-like pulsation (depending upon sample and voltage) on moonlight.

Here are three D25A samples swept along with an HDS across a time exposure. You really can't "see" PWM this fast unless you know exactly how to look for it - I never noticed it until another reviewer pointed it out.

19928723585_1a23e4c744_z.jpg


And a typical D25A moonlight on low voltage vs a Quark moonlight - cellphone test and time exposure.

7939898512_17392d11b3_z.jpg


#95
Since we are splitting hairs, I think this old photo (a time exposure sweep) is a pretty good visual representation of the progression from "oscillation noise" to true PWM. L to R: SC52, Quark AA, D25A and MDC AA. I swept them all together, and fast as I can possibly swing my arms. Focus on the very bottom of the beam swipes.

14308084037_135e533055_c.jpg


IMHO: the SC52 and Quark show oscillation noise, and are undetectable with the naked eye (which I consider myself pretty good at), and an HDS will look similar, but this is not PWM. By my definition, the D25A crosses the line of true PWM (on ~3 modes) but I really need to concentrate to see this one (and it's one of my favorite lights, own a half dozen).... it is the fastest PWM frequency I've seen/photographed. The MDC AA is kinda slow, and it see it annoyingly frequently.

But if you don't know how or what to look for, my advice is - do not learn!
 
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markr6

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PFlexPro has some nice P60 style dropins and modded Convoy lights. These use 4500+Hz PWM.
 

Thetasigma

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Maratac AA Rev 2 Copper on low
Maratac AA Rev 3 SS on med and low
Maratac AAA Rev 3 Copper on med and low (prior to Oct. 2015 batch)
Maratac AAA Brass on med and low
Maratac AAx2 Extreme Green and Red switchboot models
Thrunite T10T, T10S

All are easy enough to discern as PWM using a waving test, but not in normal usage conditions.

Edit: Eagletac D25A Ti, this one seems to be in question. Manufacturer claims current control on all levels, however some reviewers have found what appears to be PWM. On my particular sample the only difference I can detect is on Low with Moon off, and Med with Moon on. If they are PWM, then they are very fast as it is barely detectable.
 
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Lou Minescence

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Nitecore EC11 - noticeable on middle modes
Olight M30 - noticeable low mode
Eagletac D25A Ti - noticeable with Nichia led not with XML2 emitter on low
 

KeepingItLight

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BLF A6 Special Edition

Moonlight mode uses a high-frequency PWM that is around 8000-9000 Hz. Most of the other modes use PWM at twice that frequency.
 

orbital

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Most EagleTac D25 series lights do NOT use PWM
likely only D25A units

Personally detest PWM & I have several D25LC2s' that absolutely don't have it
 
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orbital

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From EagleTac site:

"D25LC2 Mini runs for 100 (and up) hours on its lowest 3 lumen brightness level. The current regulated and non-PWM dimming circuit design allows constant and non-flashing output throughout its runtime for all output levels."


To say a product has a potentially negative aspect, when it doesn't, can be libel situation.


Good reason to close this thread.
 

Woods Walker

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From EagleTac site:

"D25LC2 Mini runs for 100 (and up) hours on its lowest 3 lumen brightness level. The current regulated and non-PWM dimming circuit design allows constant and non-flashing output throughout its runtime for all output levels."


To say a product has a potentially negative aspect, when it doesn't, can be libel situation.


Good reason to close this thread.

Libel situation on the internet. Oh no! The OP clearly states that disputing any claims are welcome. As for closing any threads I think that's up to the mods and administrators. On a side note the old Fenix LOD has a highly visible PWM. Per my cell phone and action cam LED screen test the Fenix CL25R lantern has a PWM but totally invisible to the eye (so it really doesn't exist as seeing is all that matters IMHO). The 4/7 twisty (mini) line and preon both have PWM but not detectable during normal use and hardly much when waving around. Potential but unproven (per my tests) of PWM on the lowest moonlight modes of my ZL SC5w. I think the Inova keychain light has a visible PWM. I should check more but am only really concerned with what can actually be seen. I do think there are some pros to PWM if done right. Reduced tint shift might be one of them.
 

jon_slider

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close this thread.
Open your mind, or maybe you should just ignore this thread if it upsets you too much. Your evidence is the mfg specs right?.. here is new evidence to consider:
[quote=reppans]I ran the time exposure sweep picture I mentioned before and now agree it does look like full on PWM, L > R, SC52, Quark AA, D25A, MDC AA, ~3 lms:

14308084037_135e533055_c.jpg
[/quote]

[quote=Racer]It's gratifying to see that not everyone buys the PWM-is-just-circuit-noise story. If it was just noise, then my camera couldn't see it.

Here's a video I did for the D25A mini showing PWM, which on their web site they say is constant-current. I believe what happened is that at some point EagleTac stopped using constant current circuits to get better tint, which their customers were/are complaining about. And they neglected to update all of their spec sheets--best of both worlds amirite?

[/quote]

ToyKeeper said:
It's really easy to see PWM. Just turn the light on and wave a thin, stiff white sheet through the beam really quickly. For this purpose, I've been using a pupil distance measurement ruler from Zenni Optical. It seems almost ideal -- thinner and stiffer than a business card, long and narrow, and white.


Here's what it looks like when checking PWM on my BST-wide on "low". Its PWM runs at 188 Hz (measured via sound tuner plus the audible whine it makes sometimes), at a duty cycle of 11% (measured via pixel measurements of that photo, and verified against official spec):

*image removed - causing login popup issues


The D25A looks similar except that the frames are thinner and much closer together. It's difficult to get good pictures of it, but I could probably do so if necessary. The D25A's frames are only about 1mm to 2mm apart, which is consistent with all my nanjg-based lights. The nanjg PWM runs at 4.5 kHz, so I'm assuming the D25A does too.
 
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Woods Walker

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Is the OP planning on updating the ordinal post with additions provided or is that static. I noticed several people mentioned the Mini and it is not listed.
 

jon_slider

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there are a few lights that use a type of circuit that some people think is a form of PWM, and others such as selfbuilt, do not consider PWM

here is an example
Zebralight SC5 (controversial) selfbuilt says it has noPwm

similar reporting/measuring differences of opinion about the definition of the word PWM occur when discussing the Eagletac

for example, selfbuilt seems to follow the strict definition of PWM defined as a pulse that turns completely off between pulses, so by that definition, a circuit with a pulse that never goes fully off, is not PWM.. however, it IS a Pulse.

for me, the definition of PWM means PULSED, regardless of whether the pulse goes fast, slow, high, or low, a pulse is a pulse, to me, my brain, and my iPhone camera

note, Im not trying to argue whether the PWM matters, is undetectable, gives headaches, etc,, Im just reporting lights that use PULSED circuits, commonly known as PWM.

so, imo maukka
"PWM is used to control output on all modes except H1. The PWM is not visible to the eye, because of its low amplitude, but possibly shows up on camera. The cycling frequency is higher on higher output modes and ranges from 775 Hz to 5000 Hz. The amplitude however is higher on the higher modes."
is correctly reporting PWM in the SC5, and selfbuilt is not, due to a difference in terminology, semantics and definition..

I think we can all agree though, that the SC5 circuit is PULSED in a way that never drops to zero, what I might call clipped PWM. There are pulses, and current drops, but not to fully off between pulses, its more like dimming down and dimming up, than just on off on off...

fwiw, I believe the Haiku and the Eagletac also use this type of clipped pulse.

note, Ive been including links any time I add a new light that I believe belongs on the list, so people can form their own opinion based on reference info. I invite others to do the same, so we can discuss any of the information available, without venturing purely opinion.. sources may vary, but please, post sources and references if you can.
 
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