Honestly it goes from absolute zero to max in the smallest increments, very slowly turning the magnetic ring from off you can set it to a level you would never know was even on unless you have dark adapted eyes.
Couldn’t really show it in pic.
Got a small brightness gain with the triple to about 630lm too.
This is a great light but has no LVP so gotta watch the cell voltage, I modded a purple efest 18350 with a protection circuit for mine.
here are my notes… visible on a scope, or in a photo, is something I track, not just visible by eye… make your own judgment whether circuit flicker matters to you…
ToyKeeper
My H51w doesn’t have PWM. My L3 L10-219 doesn’t have PWM. But the SC52 does. And while trying other lights, I found that the JETBeam RRT01 has something like PWM, but instead of a square wave at 2% duty cycle, it seems to use a steady sine wave.
Anyway, just wondering if anyone else can confirm that the SC52 has PWM on L1 with a 14500 battery.
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ToyKeeper
the L3 L10-219 and RRT01 have become my most often-used lights, with the SC52 now mostly just sitting on my nightstand for use as a night light or mood light.
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ToyKeeper
I haven’t really used my RRT01 much lately. It’s a sweet little light, but I find that it’s too wide to hold comfortably, I compulsively check and re-check to make sure it’s turned all the way off, and I apparently prefer having known output levels. I use fixed levels to gauge how night-adjusted my eyes are, and to get an idea how long I can expect the battery to last, but the RRT just leaves me wondering.
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PWM/Strobe
There is no sign of PWM on either light – both are either current-controlled, or use a frequency that is too high for my oscilloscope to detect.
I did detect some high frequency signal noise on the RRT-01 oscilloscope traces, but this was not visible:
Thank you jon_slider.
Well, then no visible flicker.
Thanks for the complimentary information jon_slider!! 
I can relate to what was said by TK ( checking if it is ON, due to the ring) but I guess I’ll make a good achievement! The light seems very good 
Thank you
Thank for the input on this CRX, specially the LVP ! Gotta watch that carefully! I won’t - probably - mod batteries, but I’m not so sure about the emitters :smiling_imp:
That triple there… :heart_eyes:
And maybe check in first if you decide to take yours apart, there is a correct procedure, doing it wrong will rip the wires from the driver which is a pain to fix :+1:
That RRT01 is one sweet light. I modded one wayyy back for soneone from XML to XM-L2 U2. I really likes it while I had it here. I got the new Imalent HR20 on a great deal and the dial control ring feels cheap and flimsy - from what I recall the RRT01 was much better made.
Yeah although the ring did have a bit of play but better grease and wrapping some thread in the groove fixed it.
I will, for sure, I’ll probably ask for help! I don’t want to mess things up on it
Thanks CRX! :+1:
Hum, didn’t knew the HR20! They seem a bit different, though; the Imalent seems to be more related to the Sunwayman v11r (click for on/off, and then control ring for output change).
Thanks for the input on this TomE
I have the RRT01 and the Niteye 10. They are the same light and interchangeable. Both take the CR123A, 16340’s and 18350’s. Niteye 10 has 11 detent spots the RRT01 is smooth spin. Both have anodized threads for battery lock out. On mine the detent spin is smooth but can be heard, not a problem and keeps the setting in place. I’ve looked for them in a recent CPF thread and this seems to be it.
http://goinggear.com/flashlights/flashlights/jetbeam-rrt0se-1-x-aa-14500-1-x-cr123-16340-cree-xm-l2-730-lumen-led-flashlight.html?\_SID=U
Thanks for the links texas shooter Meanwhile I got a deal from a BLF member, but that’s good to know it can be found around there.
I also found the Niteye10 on AliExpress: Page Not Found - Aliexpress.com
The RRT0SE is a bit different from the RRT01, as it has the other modes in the ring (I don’t like it that much, I must confess). Also, I guess it doesn’t take 18350s (at least from the specs!).
I went to see some Niteye10 videos and the “clicks” on the control ring are not so nice as the smooth ring on the Jetbeam. Though, if I couldn’t find one, I’d probably take it
Once again, thanks for your comments and links! :+1:
It arrived today, my Jetbeam RRT01 
I wanna thank to Tally-ho for selling and sending it to me This is indeed a very nice light with a true ramping UI, from barely visible to 600 lumens (specs)!
I put an Aspire 18350 on it and it will run beautifully! Maybe I’ll mod the emitter as the XML2 it has is CW and a more neutral or warm white would enhance it’s beauty!
Thanks for the suggestions of all members, and specially Tally-ho for the deal :+1:
Best regards :sunglasses:
Nice :+1:
I may “check in” with you if/when I intend to mod the emitter 
BTW, do you remember if it has a 16 or 14 mm plate? For the diameter of the head it seems 16, but I don’t want to open and close it many times before going for the mod 
Thanks in advance!! :+1:
The HR20 is a control ring light, but that’s about where the similarities end. The quality, lower range and ergonomics of the RRT01 is in a completely different class than the HR20. I briefly played with the V11R before gifting it, and I remember it being much nicer than the HR20 too. I appreciate HR20 for their attempt, so I bought one to show my support. Hopefully they listen to feedback and try again.
Just swapping the emitter is fairly straight forward but it is an unusual shaped MCPCB so you will need to reflow, it’s not really worth the effort filing down a Noctigon, unless you really want to
I think the Bezel will be glued too :weary:
I found some nice pictures of the light with the various bits disassembled on TLF that you might find useful :+1:
Thanks CRX for posting the pic and the link! It really is an unusual MCPCB, I don’t know if I will venture myself to open this light and eventually damage it…
Yesterday I made an accidental reflow, but damaged the plate and almost the LED, so I guess I won’t be brave enough! Or maybe I will, when I master the solder iron correctly
Thanks again :+1:
I bought an RRT-01 and have been enjoying the variable brightness very much. I blame MascaratumB for making me spend money… lol
I do not detect flicker with my eyes, nor with my camera
It does change brightness, using my home calibrated lightmeter, by about 10% depending which way it is facing, but If I dont move, the light holds steady regulation. I cannot detect those changes with my eyes. In fact, I probably play with the dial more than the light drifts.
note the clip is on the lower right
note change in lumens by simply rotating the whole light so clip is top left now
I dont mind a 10% change in brightness when moving the light, but Im not inclined to have a Nichia installed, as my past experience produced swings of 100% with a 219c mod in a V11R
The light I received has a very nice pocket clip, that does not interfere with the adjuster ring. However, the clip sticks to a magnet, which tells me it is not Titanium, despite the claim in the product literature.
It also has the nice Orange Peel reflector,
The low modes are just amazingly low, and it tailstands without wobbling… All good things.
The tint is predictably green, typical for Cool White Low CRI LEDs
The clip on the RRT-01 CRX got was longer, he shortened it for this pic (maybe that version was Ti?). It looks almost identical to the clip on the McGizmos, and his got a smooth reflector… different runs I suppose.
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While entertaining myself googling RRT-01 I learned that it shares design similarities with the McLux McGizmo PD:
I like to think my RRT-01 is a cross between McGizmo DNA and an HDS Rotary. Except neither of those is infinitely adjustable, and the RRT-01 has lower and higher modes than its Ancestors…
You’ve both scored some fine torches. The JB/Niteye magnetic ring lights are wonderful tools.The extreme lows are useful.It’s bezel circumference is compatible with a couple of manufacturers filter adapters. The color filters are good fun. I wish JetBeam would have continued the evolution of this design.
My TCR1, carried since 2012, only mods are a 4K emitter and a waterproof, GITD, tape disc in the lanyard recess.
That was a steel clip I shortened on mine.
Nice TCR1 :+1:
