Resolved! Mule flickers on low with RCR123s

[easilyled]

Has anyone else had this problem?

With AW's fully charged RCR123s when I turn the light from off to low, it flickers.

This seems to resolve if I then twist it to high for a few seconds and then
back to low.

The flicker only occurs on low, not high, and only with rechargeables.

Its fine with non-rechargeable CR123s.

As Don suggested, I cleaned all the contact points, ie the Kilroy spring, the
rim of the piston and the contact points on the PCB, however it hasn't
changed anything.

I am postulating that it may have something to do with the
4.2V (off freshly charged li-ions) maybe being a little high for the
GD to regulate stabley in Low. (Also maybe the Vf of the Cree-XRE in my case
is not ideal) However please don't ask me to measure anything as I don't
have the right equipment, nor do I want to take the light apart.

Can anyone shed any light on this? (of a non-flickering type) :ironic:

 

[McGizmo]

Re: Mule flickers on low with RCR123s

Yup, I am stumped here...

 

[cave dave]

Re: Mule flickers on low with RCR123s

Do you mean PWM? My Ti PD displays a very high frequency PWM on low.

 

[jumpstat]

Re: Mule flickers on low with RCR123s

After reading this thread, I was a little worried. So when it finally arrived this afternoon, I tried both a SF primary and AW's R123a protected cells and happy to report that they both worked as normal without any flickering or sorts.

 

[easilyled]

Re: Mule flickers on low with RCR123s

cave_dave, I don't think the Mules use PWM, so if you have the impression
that they do, then I guess you are experiencing a slight flicker too.

As for mine, either the problem is easing up or the flicker is so slight
that I haven't considered it worth chasing up.

 

[LouRoy]

Re: Mule flickers on low with RCR123s

I have noticed some flicker on my Mule when on low and using Surefire primary batteries. If I go to high and then back it off to low, the flickering stops. I have not yet tried cleaning the contacts to see if that will eliminate the flickering.

 

[McGizmo]

Re: Mule flickers on low with RCR123s

I have noticed some flicker on my Mule when on low and using Surefire primary batteries. If I go to high and then back it off to low, the flickering stops. I have not yet tried cleaning the contacts to see if that will eliminate the flickering.

OK, let me qualify this as a guess because I do not understand the innerworkings of these black boxes. When you go from low to high, you are adding to the contact force on Kilroy as well as wiping kilroy across a section of the piston lip. This sure sounds like a cleaning of this contact area. Now whether that is what makes the flickering to away, I have no idea; it sounds like a reasonable cause - effect to me.

The GDx2 used in the mules is the same driver that is in all of the Ti lights with the exception of the 2x122 cell versions.

I still am clueless as to what is going on here or to what extent it is due to a particular case or common, in potential to all. I suspect this is an isolated incident and replacing the converter in easilyled's light might make a difference in his light.

The other problem is that the awareness of a flicker is not consistent from one of us to another. It seems that I am very poor in detecting it and I base this on back when there were some Aleph's that had flicker issue on low for a number of folks. I couldn't perceive this problem in lights I built even though the customer receiving it could. :shrug: :thinking:

 

[Codeman]

Re: Mule flickers on low with RCR123s

I had another maker's light do the same thing. It flickered on low, but running it for a few seconds on high would fix it. We ended up replacing the board when nothing else worked. Although the exact problem was never found, I've always suspected that there was a slight fracture in a component somewhere that just a slight amount of heat would overcome through expansion.

 

[Dog Chaser]

Re: Mule flickers on low with RCR123s

I don't know if this helps, but I have no flicker on low with my mule. I do have a flicker on low with my PD-S when I use AW's 750mA rechargeables. I've tried both Tenergy's and Powerizer's and there is no flicker. The Tenergy's and Powerizer's are 3 volts, but they come off the charger at 4.2v just like AW's. I've tried a number of different AW cells and get the flicker with all of them. Could it be something to do with the protection circuit?

 

[jumpstat]

Re: Mule flickers on low with RCR123s

Update: What I did this morning was run the mule on high for a bit let it cool down for 5 minutes and switched it on low. I took a another light that uses PWM, Liteflux LF2 and also swithched it on low and put it side by side. Its been running for half and hour and comparing the output my mule does not show any flickering. Same with the SF primary cell.

 

[easilyled]

Re: Mule flickers on low with RCR123s

I'm happy to report that I haven't noticed any flickering recently :thumbsup:

The problem seems to have resolved on its own.

Maybe it just needed breaking in. :naughty: