SF's KX1 & KX2 dual output questions ???

shiftd

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Hi all,

So I have decided that it is time for my next flashlight purchase and the new E2L dual output is the candidate.
However, there are a couple things pertaining to the new dual output heads that bug me, that I hope you guys can help answer:

1. what are the voltages rating for the KX1 and KX2 heads (KX1 is on the new E1L, KX2 is on the new E2L). More specifically, can I run either KX1 or KX2 from single liion rechargeable with typical voltage 3.7V? I heard that these new heads are specifically designed with 3V and 6V input voltage, respectively, in mind.

2. How does the beamshot of the head look like? I have seen the 3rd generation tight beam of KL1, and the older first generation KL1, but I believe I have not seen the beam of these new heads. I am not sure how these new dual output heads compared to the previous single output heads within the same generation. please post any beamshot that you may have.

3. I believe the switching are all done within the head. if so, the heads can use any of the SF E series compatible body and switches. Can anyone confirm this?

Thank you for the help
 

PhotoGal

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Hello,

Well, I can answer #2 and #3 for you, as I recently received two SF KX2s for upgrading my older incan HA-BK E2Es.

#2 - Beam is very ringy and unevenly centered on mine, with a blob of something on the outer perimeter of beam - reflector also has a scuff mark in it. I dunno what the blob is caused by (not the scuff mark), but it detracts from the whole beam in general. On this particular KX2, the beam is very white and bright (sorry, I have no way of uploading any images or measuring the brightness); the other one has a very nice and smooth beam, but it's GREEN and much dimmer than the first one. Go figure. At any rate, I'm not very impressed :( with SF's new dual output heads and am going to stick with the single output ones instead - if they're still sold by any dealers.

#3 - Yes, the KX1/KX2 Dual Output Heads are for use with any of the E Series and the switching is done in the head by a soft press on the switch after initially turning it on.

Hope I've been of some help in answering your questions. To sum it up, I'd keep the current single output head rather than buying the new dual output ones. It's a lottery in my opinion, like a box of chocolates: 'you never know WHAT your going to get'!

Regards, Jackie
 

PhotoGal

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Hello,

Sorry, double post!:eek:

Well, I can answer #2 and #3 for you, as I recently received two SF KX2s for upgrading my older incan HA-BK E2Es.

#2 - Beam is very ringy and unevenly centered on mine, with a blob of something on the outer perimeter of beam - reflector also has a scuff mark in it. I dunno what the blob is caused by (not the scuff mark), but it detracts from the whole beam in general. On this particular KX2, the beam is very white and bright (sorry, I have no way of uploading any images or measuring the brightness); the other one has a very nice and smooth beam, but it's GREEN and much dimmer than the first one. Go figure. At any rate, I'm not very impressed :( with SF's new dual output heads and am going to stick with the single output ones instead - if they're still sold by any dealers.

#3 - Yes, the KX1/KX2 Dual Output Heads are for use with any of the E Series and the switching is done in the head by a soft press on the switch after initially turning it on.

Hope I've been of some help in answering your questions. To sum it up, I'd keep the current single output head rather than buying the new dual output ones. It's a lottery in my opinion, like a box of chocolates: 'you never know WHAT your going to get'!

Regards, Jackie
 
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Dadof6

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I have the E1B backup which I like a lot. The only problem I have is using rechargeables. If I use a 3.7 the light pulses on high, if I use a 3.0 rechargeable is pulses on low beam. It doesn't pulse using regular non rechargeable 3.0 surefires.
Don't know how it is with the E1L and E2L but that is how it is with E1B.
 

BBL

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In theory:
KX1: Boost circuit, can take anything BELOW the leds Vf (aprox. 3.7V, likely less)
KX2: Buck circuit, anything ABOVE of the leds Vf up to 6V (bellow Vf out of regulation)
 

shiftd

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Thanks for the reply guys.

Photogal,


I have seen KX's head beamshot from another thread and it doesn't look like it is THAT ringy. I can sure see a dark ring, but it is not all that bad. Is it possible that you lost the lottery?


Dadof6,

That is weird. The E1B uses SF123 battery (3.0V), why would it pulses on low?
Can you describe the pulsing? is it flickering or is it blinking? This is bad news to me as I want to use rechargeable to power my new light :(


BBL,

I see they (the new heads) are no longer using the system like the first gen 1 KL1, where you can feed one with 2.7 V up to 9V of input. Bummer.

If KX2 is a buck, that means IF someone win the lottery and got a very low Vf LED inside the head, he would be able to run the head's both low and high output as usual. Can anyone confirm this?
If this is the case, then one can just do a LED transplant on the head and then able to use it using rechargeable.
 

ttran97

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Dadof6...you can do what I suggested in another thread and put the KX2-BK head on the E1B and that will gladly accept RCR123 3.7 volts. Thread

shiftd...it would pulse on low because 3.0 volts in the rechargeables is really more like 3.0-something when it's fresh off the charger...I can't remember exactly. So this causes the light to be over driven and makes it brighter, but then the circuitry will kick in and try to restrict it from being too bright, thus the pulsing. It will be like a slow strobe of high-low-high-low...etc.

Some people have tried using rechargeable 3.0 v by running it on high for a few minutes to take off some of the charge...and then it'll run like normal afterwards.

You could also put the KX2 head on the E1e body...and run that with the 3.7 v rechargeables. Just don't put the KX1 head on the E2e body...

Runtime with the RCR123 3.7 v and KX2 head is roughly 30 minutes regulated and 80 minutes to 50% brightness.

KX2-BK on E1e-BK body with reverse clip from E1B:
 
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shiftd

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ttran97, this is good news :D

Thank you for the idea. I am gonna get the new E2L and feed it with 17670 :D
 

ttran97

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ttran97, this is good news :D

Thank you for the idea. I am gonna get the new E2L and feed it with 17670 :D

A friend of mine runs two RCR123s 3.7v in his new E2L...but I think that's driving the LED a little hard...but it works and it's a lot brighter. So if you wanna gamble a bit... :naughty:
 

Bullzeyebill

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A friend of mine runs two RCR123s 3.7v in his new E2L...but I think that's driving the LED a little hard...but it works and it's a lot brighter. So if you wanna gamble a bit... :naughty:

Nine volts should be no problem with the KX2's buck constant current regulated circuit. It should not overdrive it.

Bill
 
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