September 7, 2019

The Convoy S2+

This is another amazing $20 flashlight like the BLF-A6. It has become my favorite, but needs some tweaks to make it perfect.

It is widely available in many variants from many sellers. It uses an 18650 lithium ion battery, and sports a Cree XPL HI emitter.

Fixing the standard firmware

The firmware is said to support two group modes. This is sometimes stated as "3/5" since one group has 3 modes and the other has 5. You want the 3 mode group which omits the strobe and sos (thank goodness).

If it wasn't possible to select the 3 mode "group" nobody would or should buy this light. The "biscotti" firmware is better yet. You either have to order the light with that (which is an excellent idea, but takes some shopping), or you have to reflash the firmware.

Here is what the "standard" firmware provides:

  1. five modes:low 5%-mid 40%-high100%-Strobe100%-SOS100%
  2. three modes:low 5%-mid 40%-high100%
5 percent of 940 lumens is 47 lumens, which is what I consider a good working brightness. If I want moonlight, I will have to flash other firmware.

Switching between mode groups is simple, but not obvious if you have never done it before. Select the lowest brightness and wait about 5 seconds, the flashlight will blink briefly. At this point, hold the button down half way for maybe 5 seconds (the light will be out while you are holding the button down) and you are done. Actually it seems to work to simply turn the light out shortly after the afore mentioned blink.

Beware though. At some point you will turn the light off in the magic interval after the dreaded blink and switch back into the 5 group mode. Then you will have to dig around to find these notes to remember how to get back to the 3 mode setup. This has already bitten me, and no doubt will again someday.

First (oddly enough) a UV model

This has no modes, simply on or off. And taking it apart reveals why. There is no microcontroller! The board simply has what looks like a protection diode (to prevent polarity reversal I presume) and two 7135 regulators. So it runs on 700 mA, plain and simple.

Which is better, this or the BLF A6 ?

The truth is, they are both excellent lights and very much in the same league. The real question might be, what are the pros and cons. The bottom line answer is "it depends". I think the Convoy S2+ with the Biscotti firmware is a better light at a better price. With the stock Convoy firmware, I will take the BLF any day.

The big problem is that the stock firmware on the Convoy has this stupid "blink on low" so called "feature" that indicates something about when it is ready to be configured. This didn't seem bad at first, but becomes more and more annoying over time. I have really grown to hate it in the worst way. That aside, the Convoy is a really great light. I need to figure out how to flash the Biscotti firmware into all of my lights.

Some people are all about maximum brightness, and for those misled souls the BLF may be the best light. The BLF has a FET to deliver maximum current for the brightest modes, along with a current regulator to allow PWM for a moonlight mode. This is a clever combination, but since I could care less about a super bright mode, it does nothing for me. The bright modes on the Convoy are more than bright enough.

Biscotti firmware (and more!)

I love the Biscotti firmware. I configure it in mode 2 and have NO blinking modes along with a great moonlight mode. The perfect flashlight. Something called the Moonlight Special driver from MTN can be flashed and is recommended for a nice moonlight mode, but I can't imagine what it would offer compared to the Biscotti.

The desert tan Biscotti model

I ordered two of these, specifying the Biscotti driver and selecting only 3 of the 7135 drivers. I am very pleased. I find absolutely no need for anything brighter than the 100 percent I get from this (with approximately 1 amp of current) and the moonlight mode is therefore 1 ma (at 0.1 percent of maximum current). A year or so later I ordered 3 more and was pleased that they were still available. This light does use the Cree XPL HI emitter. The emitter can be chosen from different color varieties. I have gone with the 3A "neutral white" based on my experience and satisfaction with the BLF-A6 using an emitter with this designation. I have had no regrets about this. 
XPL HI V2-1A 6500-7000K
XPL HI U6-3A 5000-5200K
XPL HI U6-4C 4200-4500K
XPL HI U3-7A 3000-3300K
Interestingly, you can also choose how many 7135 power drivers the flashlight comes equipped with. I am more interested in long life at sensible brightness settings than the absolute highest brightness, so I ordered my lights with 3 drivers. 
7135*3 output current 1050mA
7135*4 output current 1400mA
7135*6 output current 2100mA
7135*8 output current 2800mA

Another model (Silver with illuminated button)

I ordered this from Banggood 1-1-2019 for $21.65 It arrived (shipped from Salt Lake City) on 1-12-2019

I was charmed by the illuminated button. The listing says 7135x8 and I selected the U6-3A color bin. This has the Cree XPL HI emitter. With eight 7135 this can put out 2800mA, so it ought to be bright. They offer 4 color bins, as follows: 

V2-1A 1000LM 6500-7000K White Light
U6-3A 940LM 5000-5200K Sun Light
U6-4C 940LM 4300-4500K Neutral White Light
U4-7A  840LM 3000-3200K Deep Yellow Light
I ordered the 3A and really want Neutral White. I was nervous about this, but now that I have the flashlight in hand, it is perfect and exactly what I was hoping for.

This is a very nice light, the only possible misgiving would be the lack of a moonlight mode. In general, I very much perfer the Biscotti firmware, and it will be a good day when convoy starts shipping this as the default.

The full brightness is very bright, very possibly more than I will need except on rare occasions. A clip is supplied, which I will almost certainly never use. Thankfully it is not on the light, so I don't have to scratch the light up removing it. An overly complex, but very nice lanyard is supplied. Since I don't trust the clips, I will probably use my own lanyard made from mini-paracord.

Another order (10-10-2020)

I want the heads from two lights to build a microscope illuminator. So I visit AliExpress and try to choose an inexpensive Convoy S2+ light being sold by the Convoy store (why buy a clone of a well proven product from China?) I find a light selling for $17 and order 3. It says it is an S3 and has the Cree XM L2 LED. I order it with four current regulators and the 3B color bin. The 3A bin is not available for this emitter, the descriptions are: 
XML2 U2-1A 6500-7000K
XML2 T6-3B 5000-5200K
XML2 T6-4C 4300-4500K
XML2 T5-5B 4000-4200K
XML2 T4-7A 3000-3200K
The listing says: Convoy S3 Cree XML2 LED Flashlight Camp Lanterna S2+ Plus Mini Linterna Led 18650 Flash Light Tactical Hand Lamp Work Light The head has an "integrative structure" rather than a brass pill, so we will have to see about that and modding. Reflector is orange peel.

Another Convoy (Red)

I purchased yet another pair of lights (so I now have 3 pairs of white light Convoys. This one I purchased to get the red anodized aluminum parts. I intend to swap the innards of my UV Convoy into this casing, so I will know that the "red thing" is my UV lamp. I also want to use the heads from these lights as a microscope illuminator. The reflector is orange peel, which yields a more uniform and spread out beam.

I paid $18.36 each for these. They have the Cree XM-L2 emitter, which is virtually indistinguishable from the supposed snazzier new XPL HI. I ordered mine with the T6-3B tint (5000K) and eight of the 7135 regulators. Each gives 350 mA, so 8 of them gives 2.8 Amps of current at full brightness. In retrospect this is silly and the minimum of 3 regulators would be just fine, but no harm done.

I switch it immediately into the second group (without flashing modes that I hate). This gives me 5, 40, and 100 percent current. This means I get no moonlight mode. I will have to figure out how to flash the Biscotti firmware to get that. Also the low mode is 5 percent of 2800 mA, or 140 mA, which is plenty bright enough for my uses, and definitely not a moonlight mode. The high mode at 2800 really serves no useful purpose -- especially with the wide beam of the orangle peel reflector. It might make some sense with a more focused beam for certain uses (like shining down deep mine shafts).

A third Convoy (Blue)

This pair cost $16.29 each, and I intend to give them to my wife so she has a quality flashlight and with her own distinctive color. These have 8*7135 and the T6-3B emitter (5000-5200K). The Aliexpress listing says it has an XML2 emitter and will drive 2800 mA to get 1000 lumens.

Features and discussion

There are several features that I consider mandatory on a good flashlight. One is that it either does not have a strobe mode or that it is very well hidden. The second is that it will accept flat top batteries without any special effort. The last is that it should have a low brightness "moonlight" mode with a vastly extended run time.

The Convoy has springs at both ends of the battery chamber, so it will definitely accept flat top cells. It does have a strobe mode, but the Biscotti firmware only offers it in certain "mode groups", and group 2, which I like the looks of, omits it. And if you buy the light with Biscotti firmware, there would indeed seem to be an excellent moonlight mode.

The Biscotti firmware has one "mode group" that offers 0.1, 1.0, 10.0, 35, and 100 percent -- presumably of the max current, which in my case is 1050 mA. I find I use my BLF-A6 in a 50 lumen mode (134 mA), so my bet is that the 10 percent selection will be exactly what I want most of the time. The Moonlight mode on the BLF-A6 draws 3.4 mA, so the "0.1" mode on the Convoy should draw 1.0 mA -- which should definitely be a moonlight mode.

Feedback? Questions? Drop me a line!

Tom's Light Info / [email protected]