making 3. Batch Texas Avenger "TA" / Bistro HD OTSM drivers fully tested running Bistro or Narsil, Clicky or E-switch, SIR800

As the deamnd for those driver is still there and my 2. batch is already sold out before I have shipped the first driver,
I am going to do another batch if enough BLF-lers are interested, you may spread the availibility of those drivers on other forums,
but I am not planning to go into mass production

Bistro-HD OTSM can be ordered in next batch, as it needs special parts and is hopefully bug free

If you want fully assembled and tested drivers reply here
Flashed and thermal calibrated MCUs are included.

This batch will be reflow soldered by hand, got enough expirience in 2. batch

Availiable options:

there are different sizes availiable 15, 17, 20, 21 and 22mm
those are cheap on the PCBs from Oshpark so I may end up with some unused boards
30mm, 38.5mm and 46mm SRK are possible as well, but add costs depending on size

Information about this driver series here

There will be a very good SIR800 FET used
You can choose a custom number of 7135 less than the maximum

can be equipped with Attiny 25
running Bistro
or Attiny 85
running Narsil Triple v1.4 latest version with fixed bugs
Narsil manual, a lot options to configure this one

NarsilM availiable for this batch

Drivers will be fully tested before shipped

Narsil v1.4 driver will be thermal calibrated as well
you can choose the temperature for stepdown,
the time for stepdowns depends on the lights size/heat, a Pocket rocket off a 14500 high drain will need a shorter time than a Convoy L6
standard will be 60°C
standard time between steps will be 45s

temp calibration with heat gun

there are 3 main options for 2S Narsil for lights like Convoy L6
Narsil v1.2 utilising low voltage protection on pin7
Narsil v1.4 utilizing indicator LED on Pin 7, has some bugfixes and temperature protection
NarsilM it is possible to choose between indicator pin and LVP the whole settings are reduced for an easier handling for the Q8

For 2S lights that use only a sideswitch or you dont lock out the light a LDO is needed,
the zener mod has a very high parasitic drain so this is only suitable for Bistro drivers

2S LDO is availiable for 17, 21, 22, 26, 30 and 46mm
2S Zener Mod is availiable on all sizes
Piggyback LDO on other sizes possible adds 1.5$

efficiency advantage over Fet+7135*1

this is just an example, keep in mind that triple hotrods get more gain than a single emitter light


for 17mm Board will be phosphor bronze in 2 lenghs
for 15mm board the short spring fits or the long upside down
All drivers come without soldered springs, to stay below 10mm envelope thickness which is 2.2€ cheaper to ship

long spring

short spring

For larger boards those springs are good

you can choose soldering paste
recommendedn with lead
on request lead free 96.5 % tin, 3% silver, and 0.5% copper


12.5$ TA Bistro / Bistro HD Attiny25
14$ Bistro HD OTSM changed capacitor brand and volume discount >10

14.5$ Narsil v1.4 Attiny85 with temperature calibration
15.0$ Narsil v1.4 temperature calibrated, 1S LVP calibrated to any value you want

NarsilM Attiny85
13$ flashed no settings,
14.5$ with temp calibration and max temperature preset,
15$ with calibrated 1S or 2S LVP / temp calibration and max temperature preset, this version has no indicator LED

per spring add 0.3$
soldered springs are possible, but it adds 2.5$ shippin costs
30mm add 1.5$
38.5mm add 2.85$ if 3 boards come together
46mm add 4.5$ if 3 boards come together
Zener mod add 0.7$
LDO 1.2$ 21mm and bigger only
LDO 17mm add 3$ more expensive parts

Bistro or Narsil customized modespacing adds 1-2$ depending how many groups you want changed
or you suply a hex add 0.5$

Bistro 2S Zener mods or Narsil v1.2 2S LVP needs to be adjusted with a customized voltage divider to the MCU add 1.5$

Bigger diameter than 30mm I will build only if multiples of 3 drivers are requested or the board price goes up to compensate the unused
38.5mm add 2.85$ if 3 get ordered, if only 2 add 4.3$
SRK size add 4.5$ if full 3 get ordered
SRK Size with more than 7 AMC7135 Bank add 1$ For 16 AMCs

2$ envelope shipping worldwide
Tracking + insurance up to 25€ adds 3$
insurance up to 100€ and tracking adds 5$
Insurance above 100€ and tracking adds 7$
1€ Germany

Bistro HD OTSM will be possible, but at a little higher price for the more expensive parts

Interest in more drivers:

1 Lowtech: 1 30mm L6
2 KawiBoy142: (2) 38.5mm Narsil LDO piggyback for a 2S3P Courui D01 piggyback LDO adds 3$, (2) 22mm 2S Zener Mod Bistro need to tune the voltage divider for LVP adds 1.5$, (2) 22mm 2S E-Switch LDO Narsil.
3 Mr.Scott: 2× 17mm w/ Narsil, 1× 17mm w/ Bistro, 46mm 1S
4 Steve 42: 2x 17mm Bistro HD OTSM long springs
5 KFulton: 3× 17mm and 1× 15mm bistro HD OTSM
6 kaizer: one 17mm and one 30mm Narsil LDO
7 khuan: 46mm 2S
8 tekwyzrd: Bistro 22mm, 46mm 2S 70dCelsius 1 minute LDO full AMC bank
9 MtnDon: 2 × 17mm with Narsil e-switch, long springs
10 pinkpanda3310: 17mm Bistro LDO, 17mm Narsil
11 Kenji: 17mm Narsil, 46mm Narsil
12 solRNY: 30mm Narsil L6
13 k-wong: 1× 17mm bistro HD OTSM
14 khas: 38.5mm Narsil v1.4 Eswitch 2 blinks startup
15 bam35: 4 Bistro HD
16 Jensen567: 17mm Bistro HD calibrated LVP, 30mm Narsil v1.2 or NarsilM calibrated LVP
17 sprinkles: 22mm (1) 1S Narsil v1.4, 60°C, PO=(2B)
18 Tjhosan: 17mm (1) 1S Bistro HD OTSM ,17mm (1) 2S Bistro HD OTSM z-mod
19 JasonWW (1) 2S Narsil v1.2 LDO PO=(NO), large spring, SD=2.8V (60°C)
20 rimmer (2) 2S Narsil L6
21 Agro (2) 1S Bistro HD OTSM Attiny 45V
22 mattlward (1) 1S Bistro HD OTSM, (1) 1S TA Bistro
23 DeJaVu (1) 2S NarsilM LDO PO=(2B), SD=2.8V custom modegroup

numbers of drivers 51/58

38.5mm 3/3
46mm 2S LDO 2/3 if only 2 are taken adds 2.5$
46mm 1S fitting Q8 and SRK 2/3 if only 2 are taken adds 2.5$

How much time Lexel do I have, to give you the numbers and details of what I want?

I will buy two 17mm drivers w/Bistro Attiny25 & the longer spring. Right now I’m thinking the BLF A6 UI… The full compliment of 7135s has no downside that I am aware so would go with that. I’m sure to be missing something.

The more complete this is the better as this is my first attempt at modding.

Will be running this is Jaxman E2l hosts with 219Bs & 219Cs in triples. Any suggestions appreciated.

Any plans to offer bistro-HD / OTSM?

Bistro HD OTSM can be ordered in next batch, as it needs special parts and is hopefully bug free

Awesome! I’d love to be in for 3x 17mm and 1x 15mm bistro HD OTSM when the time comes. :slight_smile:


Long spring if they fit, please. Temp at 50C, and please use this hexfile:

and these fuses:

low: D2
high: DE
ext: FF

The customizations in that hexfile are moonlight defaulted to off, and the reverse groups have been modified to ultra low, then turbo/FET, then battcheck.


Basically I will ask people that had replied here as there is interest for at least 25 drivers, to give me a final number how many they take and send the payment instruction
When I have confirmation of people with the final number of drivers they take,
Then I will start ordering parts, and also as last time more for people who join in later

So if you tell me as early as possible a number you take for sure its better than a number higher than you take in the end

Interested in a 22mm ldo bistro or possibly bistro hd to replace the LD-29 in my Convoy L5. Single tube with 2x 26350 or double tube with 2x 26650 lii cells powering a xhp50.2 would probably be a good combination for this light. I like the light itself but the driver… not so much.

Add me for 1x 46mm ldo. Narsil 75c 30s

2S4P 18650 host to 4x xhp

for unfinished contest entry - can’t incorporate costs into budget…
another $80 on a light that lost…

Next entry: 4 lens zoomie…

next contest will be …

I’m interested in 1-2. I’ll get back to you with preferences

I’m thinking (2) 38.5mm drivers for a 2S3P Courui D01 - make it dual button - (E-switch/ tail cap) capable, Narsil.

(2) 22mm 2S Zener Mod Bistro.

(2) 22mm 2S E-Switch LDO Narsil.

2 x 17mm with Narsil e-switch, long springs

@Lexel Which springs will fit on the 22mm board?

I’m still not sure what I want sooo can I get
1x 17mm bistro LDO
1x 17mm narsil

the 22mm Board fits up to 10mm base diameter springs

Ok, no spring on the 22mm. I have some be-cu springs I can cut down and bend a bit to fit.

I got some Be-Cu springs as well, dont need to be cut and bend, they simply fit
but as you solder the positive wire to the top of the spring there is no need for low resistance spring, you can use thin steel springs
The Be-Cu springs are not nearly as flexible as steel springs, first time compressed they get shorter

Correct, the pass-through in the TA drivers means that spring resistance is a non-issue. All that matters is that the spring holds the battery in place and keeps it from hitting the 7135’s.

The potential problem is the length of the springs in the op. I’d have to measure but the original spring on the L5’s driver looks like 6 or 7 mm uncompressed.