KX1 modded with Q5 / RV7 / 130 Lumens

BigBoy

Enlightened
Joined
Dec 9, 2004
Messages
214
Location
Huntsville, Alabama
Surefire KX1 head
Cree Q5 / WC emitter
RV7 1.2 V Nimh driver

When the RV7 driver became available this fall I modded a KX1 head with the above components and really liked the result. For some reason I have not yet adopted lithium based batterys - and generally use AA Nimh batterys. The RV7 driver achieves remarkable output on a single Nimh cell. At 700+ milliamps the Q5 should be putting out about 190 'bulb' lumens which yields approximately 130 lumens out. The KX1 head is readily modable with a flat surface to mount most any LED and ample room on the driver side for any of the standard .55 drivers. Dissassembly requires a heat gun. The prototype was setup as designed with 3 levels - but after a few months I opened up back up and set it up as a single stage light (high only) and really liked the result. Because of this all the lights will be single stage.

The following chart shows output (in milliamps) with several popular batteries:

battery.jpg


This is a beamshot outdoors at about 30 feet with a fresh Eneloop:

img_0848.jpg


And some closeups of the modded KX1 light engine:

img_0863.jpg


img_0864.jpg


I took the first prototype on several camping trips and the next thing you know there are five non CPF 'civilian' friends who want a light. I purchased parts to make 10 of these - and expect to offer the remainder in the Custom / Modified B/S/T forum in a "few weeks". 6 of the heads are complete and I have 4 to go.

A group shot - the yellow cylinders are spacers when combined with a single AA cell they will equal the length of 2 CR123A's. When a E2E body is lined with card stock the AA and spacer will be snug.

The battery is an Elite 1700 from cheapbatterypacks.com. These batteries are amazing with the RV7.

img_0862.jpg


These units warm up a bit - but it is no where close the the heat a KL4 or e2e head will generate. All of the units have a wonderful smooth white beam, however they were very difficult to center exactly and if you rotate the flashlight while shining it against a while wall - you may notice some unevenness. The beam pattern tends toward being a thrower. The F04 beamshaper softens up the beam for reading / indoor use.

Bob
 
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BigBoy

Enlightened
Joined
Dec 9, 2004
Messages
214
Location
Huntsville, Alabama
It will be somewhere around $100 - but don't hold me to it! Actually the 10 heads were intended to be sold here in CPF it's just that some 'civilian' friends suprised me when they were willing to purchase them.

That's a pretty sweet setup with 1 AA. What will you charge for the extras?

schiesz
 
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koala

Flashlight Enthusiast
Joined
Mar 5, 2003
Messages
2,295
Location
Melbourne, Australia
http://www.dealextreme.com/details.dx/sku.7880

If your toroid coil looks loose or messy, let me know I will tell you the number of coils if you need to rewind. There are several revisions out there, the 7880 may be the latest. Please note, these are not regulated, they are simply coil based boost with no hardware IC driver except for microcontroller doing the PWM. The manufacturer initials can be found on the other side of the board.

The same circuits are also found in the MTE lights many months before it was made available on CPF.
 
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gunga

Flashaholic
Joined
Nov 29, 2006
Messages
8,080
Location
Vancouver, BC, Canada
Just reviving an old thread.

Was there a problem with the orginal 3 mode setup for the RV7 board? Is the singls stage mod reversable (ie just desolder a wire?). DId the original 3 modes work well? I know the DX version is kinda lousy.

Does anyone have any more of these RV7 drivers?
 

Illum

Flashaholic
Joined
Apr 29, 2006
Messages
13,053
Location
Central Florida, USA
now that the thread have been revived [somewhat]

Did you save the existing drivers? Can I buy them off of you?:D

3V boost circuits that applies that low of an output current is not easy to find when your trying to avoid DX:candle:
 

BigBoy

Enlightened
Joined
Dec 9, 2004
Messages
214
Location
Huntsville, Alabama
I just sold my last 2 original RV7 3 mode 16mm drivers to another CPF'r yesterday! However I have a dozen or so of the 17mm 19 mode RV7 type driver that I purchased from DX. These can be wired single mode simply by connecting led- to board ground. You can have as many as you want for $3.50 each plus $2 shipping (domestic).
Bob
 
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