Why does my P3D Q5 flicker on Low mode only?

[Face]

Hi,

I have a P3D Q5 (well, actually, it's a P3D Rebel 100 body with a replacement Q5 head - in case that makes any difference) and I noticed last night that it has a subtle flicker on Low mode only. I can't see it happening on any of the other modes (other than Strobe ) This isn't the low battery warning flicker - I've seen that enough times to know what that is.

I've De-oxit'd the tailcap spring and the positive battery point but the flicker is still there, although it may be even more subtle now - or it could well be placebo

Anyone have any ideas on what might be causing this and how to rectify it?

Thanks,

Face

 

[chaosmagnet]

I own a P3D Rebel 100 and a P3D Q5, and I haven't seen this with either of them. Is it possible that you're seeing PWM http://en.wikipedia.org/wiki/Pulse-width_modulation ?

 

[zipplet]

Afaik this fenix light does not use PWM. It's possible you're seeing a regulation issue at the lowest level. The TK40 has a similiar issue (but hard to notice) on low if you follow a set sequence to cause it which is:

- Light ON (in any mode other than low)
- Cycle modes to get to low
- Light OFF
- Light ON