Can I swap the driver of my SkyRay King?

Google Sky Ray King.
I do not have the light.

The Sky Ray King is essentially the same light that you sell under a different name here: http://www.lightscastle.com/product/fandyfire-uv-s5-cree-xm-l-t6-3-mode-3000lm-3-led-white-flashlight-w-strap—yellow-4-x-18650-130032

I’m currently working on a King driver mod, unfortunately I don’t have much spare time currently… I’ll post results when I’m done (if I succeed, that is), may take some weeks.

Maybe you will want to rethink about the spacing values for the modes: output is not linear with current, with your amperages I feel you will end up with 4 very bright modes, very close to eachother, and no real low.

For example, a light that I like a lot for the spacing between modes and good low, is the Lumapower Dmini-VX, and it has 2,5A - 0,50A - 0,12A - 0,02A

Weeks!!! You have 7 days J)

You may very well be right, I haven’t done a lot of research into it.

It wouldn’t be a straight up driver swap. The King uses an e-switch that doesn’t rely on power interrupt to turn off or mode flip. So the mode control EPROM of the circuit never really completely powers off. AFIAK no one makes a drop-in replacement driver that uses an e-switch.

Likewise, modding it to 3S or 4S 18650 would require a lot of DIY fabrication too, at both the + and - end. You would have to effectively isolate the cells from the - tailcap end and from the + head, and in place of the “P” connection wire everything up for series cells. Definitely an advanced mod, for a builder with some serious DIY fabrication skills.

Add a small latching circuit, I assume there is voltage at the switch. Shouldn’t be too hard to do.

It might be easier to re-program the EPROM. Its been done before on other lights, both on CPF and BLF. No one has attempted it on a SR King though.

A latching circuit looks something like this

I have EEPROM readers, when mine comes I will give it a go.

Cool… keep us updated on how that goes. You should also kill the low PWM while you are at it. IIRC its in the vicinity of ~100-130 Hz which is way too low for almost everyone.

If anyone has a picture of the EEPROM in the driver board it will be a start.

viw, see this thread for some nice high res pictures of it.

https://budgetlightforum.com/t/-/11403#comment-234223

Did you post this from m.phone or tablet?

I am waiting until someone finally find the way to change this stupid modes (hi-lo-strobe) and then I’ll get the King :- )
Hope to insert DrJones’s ramping sw :- )

Posted it for you.

Here the correct URL is.

http://www.youtube.com/watch?v=Foc9R0dC2iI&desktop_uri=%2Fwatch%3Fv%3DFoc9R0dC2iI&gl=GB

It’s not just an EEPROM, but a micro controller. I have not yet read of someone being able to reprogram these unmarked Chinese ones. Seems to have a PIC pin layout.

There might be space enough for three NANJG105C, one master and two slaves. A master with a firmware suitable for electronic switches (Tido made one for PIC, I made one for the NANJG/Atmel) would be a possible solution.

While you are hacking around in there do something about the standby current. It is around 100-1000 times higher than it could/should be…

Curious what is the parasitic drain on this light?
How long does it take to drain 4-18650 from a full ~4.15V charge down to (say) less than ~4V

Its not a deal breaker in my book though since power can be 100% cut off by unscrewing the battery tube a ~half turn… I’m just curious more than anything.

thanks

Batteries in SRK are in parallel...total volts is 1S, so 4.2vdc is max voltage you will get