[SALE] lighted tail boards, rainbow or custom color combination

I am finally starting sales on my lighted tail boards

how it began can be read here

each generation adds more features

Generation 1
simple 2x3 LED with balance resistors optional trimmer
each LED has its own balance resistor so different LEDs can be combined
2 channels can be dimmed with optional trimmer
it is advised to use LEDs with similar forward voltage (CW, WW, blue, ice blue, pink or red, orange, yellow)
if different colors used the LEDs with higher forward voltage dim out with lower battery voltage, this can be used as battery indicator

Generation 2
2x4 or rainbow added voltage stabilisation
2.8V 18uA LDO used to keep brightness stable down to about 3V battery voltage
trimmer optional

Generation 3
2x3 +1 LED added low battery warning and LVP
inner ring lights up with constant brightness
low battery: inner ring gets switched off and one red LED turns on to indicate low battery
LVP: all LEDs are switched off 2.8V LDO and IC standby current of 21uA remain
low battery and LVP can be set to custom voltages

The tail boards run with an 1kOhm resistor as bleeder this works with relative low current drawn from LEDs
Note the more current the LEDs draw the more voltage drops on the bleeder so battery voltage is higher than the calculated values

With standard hysteresis there is a fade between both LED groups and LVP shut down
this is PWM because when the comparator switches the LED off, then the voltage drop on the bleeder is gone,
so it switches on again just to notice that with the voltage drop again it is too low, aso
with battery voltage dropping the PWM cycle gets shorter and fades out

OD 17, 20, 22mm Omten 1288 (6.5mm hole)
Gen 1-3 available

OD 17, 20 9.5mm switch hole for bigger switches
Gen 2 8 LEDs or Rainbow no trimmers

OD 20mm Convoy L6
Gen 2 Rainbow or 2x4

22mm Omten 1288 (6.5mm hole)
Gen 2 rainbow

[LED colors] (top are most efficient, bottom inefficient)

LED color and each single LED current based on my “0.5mA” brightness level

green 14.1uA
blue 21.2uA
ice blue 25.2uA
pink 37.7uA
WW 40.2uA
red 50.9uA
CW 66.7uA
orange 124uA
yellow 206uA
emerald green 349uA

my LED brightness scale is based on my Rainbow+WW boards total current while LEDs seem same brightness

basically I have 4 levels “1mA”, “0.75mA”, “0.5mA”, “0.3mA”
this does only reflect on rainbow boards with WW the total current drawn

on 2x3 or 2x4 boards the total current depends on used colors and brightness level (“0.3-1mA”)

for example you order a “0.5mA” pink/green 2x4
18uA LDO + 151uA pink + 57uA green
total current 225uA
now we add 20k trimmers for brightness adjustment
total current at min trimmer level 95uA

It is possible to define a total current consumtion with trimmers on max position
I got a very complex table to calculate the needed resistances


single and 2 colored

1. Generation 2,75€
trimmers optional 0.4€

2. Generation 4,5€
trimmers optional 0.4€

3. Generation 6,5€
20mm 2x3 trimmers optional 0.4€

1€ per order and 0.4€ per board

for custom mix of more than 2 colors
1.5€ per order for each different color combination

+ the fees for commercial PayPal which are quite high on small amounts


priority air mail worldwide
1€ bubble wrap envelope

2,7€ optional tracking with 25€ insurance

DHL (Express) worldwide parcel
Hermes EU
on request, but relative expensive

First prototype of Generation 3 working

all 3 on a 1kOhms bleeder
First a big voltage jump you see

- generation one changes brightness with voltage

  • Generation 3 gets in LVP shutting down completely (The switch point needs likely to set a bit lower)

Nice, does this mean you’re ready to sell a complete tail light switch?

Awesome work!

what are the lights this will work with?

will it fit 6p, malkoff, boss...etc?

GEN 1, 2 are ready to build and sell
as usual custom color combinations possible, like rainbow up to 8 different colors

GEN 3 atm only with 6+1 colors,
17+20mm mm one channel no trimmers
on the 20mm with trimmers in 2 different groups

I have made one with 8+1 with cut out boards for easier production 20mm will be mouse bites
but this will take about 10-12 days to get the boards delivered

of course the further the development goes the more it will cost (parts, labor and development time)

Nice! looking to get my hands on some generation 3 boards.

Electrically should work with any driver that’s not effected by adding a 1kohm bleeder.
Should fit in 6P and 6P clones tailcaps, can’t install in malkoff MD or boss tailcaps as the switch is inserted from the top.

can replace basically all switch assemblies that use a washer on top of the switch to press the switch boot against the tail hole

adjusted the prices as building those took more time than thought
time to assemble those is more than on drivers, trimmer price reduced

Lexel, can you explain how these pcb wire up?

Also, does it effect the driver circuitry in any way?

is wired in parallel to the tail switch
and a 1kOhm bleeder on the driver

not all drivers like bleeder resistors

Okay, that’s what I was thinking.

We are talking about them on the Convoy L6 thread here if you want to see.

Do you know what drivers need the resistor and which don’t?

Do your L6 FET drivers need the bleeder resistor?

Most 2S drivers LDOs act as bleeder

How about a gen 3.1 idea?
3 + 3 (or 4 + 4) LEDs would be placed alternately. 3 blue for “normal operating” light, 3 red for low voltage indication. The red LEDs would be blinking type like this.
So if the battery voltage is low then the signal will be conspicouos.

if i would find time to update

gen 3.1 is already produced and here
it is 8+3

but atm i can barely spend any time to flashlight most gets eaten up by mails and PMs I am even behind like 2-3 weeks on old orders

Gen3 20mm with trimmer
inner LEDs in 2 groups star pattern with 2 trimmers, mainly for 2 different colors
outer Low battery fixed brightness

Do you use 10k or 100K trimmers?

I just bought some 100K 3x3x2 to try out on some of my lighted switch mods. It should definitely beat having to constantly swap resistors to find that sweet spot between brightness and current consumption.

Edit, looks like you use 20K. I wasn’t sure if that would be enough.

I got different values from 2-50k

Will the R7 - R12 resistor hit the shelf? I look at some common flashlight and the LED may hit the shelf for those. Can it be put somewhere like the back? I guess the back need to have space for the top of the switch though..