Petzl Tikkina2 - NEUTRAL FLOOD MOD!

As detailed in this thread, I had gotten a Petzl Tikkina2 for my daughter as she likes to use it during story time right before bed (and another for my sister for the same reason). It's a great little headlamp but not quite suitable for reading as the beam was too narrow, the hue was too blue and even on the lowest setting it was a bit bright for dark adapted eyes. My sister attested as much after using it for about a week and shelved it in favor of my bro-in-law's LL H7 due to the low floody beam.

After doing a little reading in the LED forum, I found a thread disucssing the Radio Shack 276-0017 5mm LED (hereon just RS) and decided to grab some to modify this headlight.

I was initially a little concerned about the donut hole this LED produces (details in the linked thread above) but couldn't be happier with the end result (Bolster, I think you're gonna like this one too but it likely won't qualify for your flood list since this is a mod).

Given I didn't have a lot of time for documentation, here are the annotated steps:

After removing the two T5 torx screws, I removed the main module. Here's a front and top shot:


And a pre-mod beamshot as reference:


Removing the original LED and putting it back in is perhaps the trickiest part of this mod given there isn't too much room to work with. Once I removed the right LED, I used desoldering braid to clean up the excess solder to make insertion of the RS easier:

(I must confess that in my younger (and less wiser/patient) days, I would've forgone this step which would have made this mod a lot harder).

I used the faceplate as a LED holder to ensure that I soldered on the RS at the correct angle and depth, the RS is slightly larger and fits into the faceplate snugly. As a result of this, I noticed that the beam was spot on w/out any adjustment necessary as initally the original LED's (which are a bit smaller) were slightly misaligned causing an imperfect beam when projecting onto nearby items/walls.


Here's the original LED, notice the slight gaps around it:


And a side-by-side comparo shot:


And a comparo beamshot after I repleced one LED w/the RS one:


Additional comparo beamshots (right shot stepped down to emphasize donut hole):


It looked pretty good so I wrapped up the rest of the upgrade and put it all back together.

Umodded and modded comparo:


And now the moment of truth, comparo beamshot (L to R: unmodded, modded, H31w):


Check out that nice neutral tint!


And of course the requisite beamshot on the wall (pure flood baby but w/very subtle donut hole):


Shifted to the top-left to emphasize donut hole:


And some Side-by-side w/unmodded Tikkina2 (bottom shot stepped down):



Due to the floody beam of the RS, it lost a bit in throw but again I'm very happy w/the results. Here are the specs between the two:

(Throw & Beam width in inches, Angle in degrees, X = Angle/Beam)

So how's it in real world use? Here are some comparo shots of my daughter's favorite book lit by various sources.

Reference shot under Fluorescent (1/25 f2.7, Daylight WB, slightly warmer than what my eyes see):


Gen1 H501 on Low:


Tikkina2 Neutral Flood Mod:


Tikkina2 unmodded:


And last but not least, some comparo shots between the RS (left) and original LED (right):



Notice how the original seems to taper off towards the tip, perhpas this enhances the throw? Not sure exactly how the dome shape affects the beam but it would be nice if there was a program that could help you calculate that.

Anyways, hoped you guys enjoyed this little mod. I'll try to get some additional beamshots later next week.

Cheers,
Tim

thanks for the great write up. especially liked the shots of the book. i'm in the process of replacing the 5mm leds in an older BD Spot and was going to use green leds. but now i might try the RS leds.

Edit (4/11): i did the mod with the RS leds and am very happy with the tint. the RS leds have the same tint as the WD CREE main led on the lamp. i guess that makes it more of a cool white than truly neutral. still, it's a vast improvement over the violet hue of the stock 5mm leds. the RS are dimmer than the stock leds, but the light is more useful now for indoors and around camp.

Edit (4/11): after popping some fresh batteries into the modded lamp, i have to correct my earlier assessment of the tint of the RS leds. they are definitely warmer than the WD CREE. i would post pics, but my camera setup takes terrible beamshots.

Very nice mod! Looks pretty much perfect for your intended use. (And a great write-up too!)

Boffo mod. Love it.

@RS5K, awesome, you gotta post some pics some time!

As a further update, I analyzed the board and it's an extremely simple circuit. The 3-way switch simply routes between H-L-Off w/H going to R1 (I think) and L going to R2. These resistors can be switched out to customize the HL to exactly the levels you'd like:


I was thinking of swapping out the H to a lower resistor and the L to a higher resistor so as to get higher/lower outputs respectively. Now just gotta go look up what those values mean.

Cheers,
Tim

R1=51ohms 1%, R2=47ohms 1%. I guess on low the LED connects to R1 or R2, when on high R1 and R2 connect in parallel to make a 24.46ohms equivalent resistor.

i think R1 is a 52 ohm 2% resistor, R2 a 47 ohm 2% resistor.

Edit: didn't see Microa's post. didn't mean to repeat the info.

Very nice mod

Thx for the replies guys. I finally got some resistors but in trying to determine what to replace, I'm confused by what seems to be a 5th band of color on both of these resistors as well as the DMM reading on R1.

I'm a relative novice when it comes to calculating/interpreting electronics/circuits, so please bear with me:

For R2, I read that as a 47 ohm but @ +/- 5% tolerance due to the Gold band as 4th stripe (were you guys in fact reading the 5th band - brown?). I get 47.6 ohm on my DMM so this matches nicely.

For R1 though, I read this as 51 ohm @ +/- 10% tolerance due to Silver band for 4th stripe, however, I keep measuring only 5.3 ohm for this resistor (of course not isolated). Even if the two were connected in parallel by default (as surmised by microa), that should work out to 24 ohms or so.

So I jumpered the battery connection to close the circuit and then measured resistance on one of the LED's leads as follows:

Off = OL (as expected)
H = 5.6ohm
L = 53ohm

Based on these readings, would it make sense that when in H, it's hitting the single 5.6ohm resistor and then in L, it connects the 2nd resistor in series w/the first for combined 52.9ohm?

I'm basically trying to figure out two things:

1) How the resistors are used (paralell or series)
2) Which resistor(s) is used in H and L

so as to know what to replace them with. FWIW, the light draws about 100mA on H and roughly 22mA on low on 3 x 1.33V freshly charged NiMH Sanyo AAA's if that helps at all.

Anyone want to hazard a guess?

Thx!,
Tim

turboBB said:

Thx for the replies guys. I finally got some resistors but in trying to determine what to replace, I'm confused by what seems to be a 5th band of color on both of these resistors as well as the DMM reading on R1.

I'm a relative novice when it comes to calculating/interpreting electronics/circuits, so please bear with me:

For R2, I read that as a 47 ohm but @ +/- 5% tolerance due to the Gold band as 4th stripe (were you guys in fact reading the 5th band - brown?). I get 47.6 ohm on my DMM so this matches nicely.

For R1 though, I read this as 51 ohm @ +/- 10% tolerance due to Silver band for 4th stripe, however, I keep measuring only 5.3 ohm for this resistor (of course not isolated).

Click to expand...

based on this chart, on a five band resistor the fourth band is the multiplier and the fifth band is the tolerance. so R2 should be yellow (4), purple (7), black (0), gold (.1), red (+/-2) = 47 ohm +/-2% and R1 should be green (5), red (2), black (0), silver (.01), red (+/-2) = 5.2 ohm +/-2%. i thought the fourth stripe on R1 was gold, but it's silver right? these ratings would be consistent with your measurements.

i can't answer the rest of your questions though.

Edit: dude, i'm either color blind or my monitor is jacked cuz i still see the brown bands as red... but they are brown right? i'm talking about the 2nd and 5th band on R1 and the 5th band on R2.

OK. Sometime it is very confusing to read among Brown, Red and Orange for some manufacturer's product.
Now the picture is clear. 5 band resistors should be read 1st band for 1st digit, 2nd band for 2nd digit, 3rd band for 3rd digit, 4th band for multipiler, 5th band for tolerance.
R1 reads Gr, Br, B, S, Br = 510 x 0.01 1% tolerance = 5.1 OHM.
R2 reads Y, V, B, G, Br = 470 x 0.1 1% tolerance = 47 OHM.
I guess they don't connect the resisters in paralell. 2 resisters connect in paralell will reduce the resistance ( 1/Rn = 1/R1 + 1/R2 ...... to n ).
R1 is used for H and R2 is used for L.
The Vf of the LED is not linear to the If. If you don't have the data sheet, you should try and error to find out by a variable resistor and a current meter.
According to your supplied data, I estimate that on H the Vf is 3.48V and 2.956V on L.
Please note that your LED is rated 25mA, typical Vf 3.3V Max. 3.6V
100mA on H has already over driven the LED. Don't drive them more than 150mA otherwise thier life is very short.

Thx for the replies! OK, so there are 5 band coded resistors as well (I thought there were only 4).

@RS5K, yes, those are brown (at least they look brown to me). The pic accurately depicts what I see in real life. How about this shot:


@microa: If they are in series then that makes life MUCH easier. I measure 3.39V on one of the LED's leads on H and 2.83V on L so you're pretty spot on. I'll keep in mind re: the current but wouldn't mind if they are overdriven and ultimately short lived. It'll give me an excuse to test some other LED's. :thumbsup:

Thx a lot guys, this has been very helpful! lovecpf

Cheers,
Tim