Attention! Solution for most of those next mode memory drivers!

It adds medium and strobe

Which modes were there before?
Thanks for the information, never read that here…so if anyone has a link I would be happy.

I have seen this some times on drivers but never knew that there is a possible function.

I just made this:

https://budgetlightforum.com/t/-/20735#comment-453016

Thanks for clarification, I have some 5 mode sk98 driver flying around in my parts box. I will look later if it had the 0R connected on stock…

as racer did above.very easy mod don’t need any spare parts.

I do not understand. Why not just remove the capacitor?

If you remove capacitor you will only have one mode, first mode that is programmed (in most cases MAX).

Because without capacitor the memory will erase in zero time. You will never be able to change mode. Like a single mode only.

I made some single mode but decided against the removing because i wanted the option to go to other mods, this was made with 22k resistor.
So I can borrow it to anyone all they see is high but with a very short quarter press I am able to use all 4 other modes if needed…

Can someone link to a schematic of a driver that uses a cap to make the memory work? I am not understanding its implementation.

There is a backup capacitor, that is recharged at every startup, connected to the power pin. It uses brownout detection that is implemented in microcontroller and at each restart it checks for brownout flag (if the mcu restarted itself due to low power voltage/mode change/ or if it was turned off for a longer time). If you don’t add that resistor it stays powered in brownout mode thus it changes the mode at startup.

Correct me if I’m wrong :slight_smile:

Hey everyone, I would just like to share a discovery I made. Maybe this is already known, but I haven’t come across it on the forum yet.

Instead of soldering a resistor to short the capacitor, I just used a light pencil to draw a faint line between the 2 capacitor terminals. Result: Modes are preserved, resets back to high in 2 seconds. Easier than soldering tiny components.

The only danger that might occur with this is you might shade too much causing the capacitor to discharge too quickly making it one mode only? Hasn’t happened to me yet, so maybe that’s just me thinking too much :stuck_out_tongue:

Nice find! Good sharing. I expected this to work but never actually did it. Graphite line would conduct electricity in a few tens kOhm territory so IMO should be ok to do this. The lowest resistor I ever used was 47k I believe, so far no problem with that.

My idea (which I never tried) was graphite + PVA glue. Pencil trace by itself is not too reliable, which the glue should help with. Since you did the pencil line, I’m gonna try this on a light + glue on top, I still have two UF S5 I haven’t mod to bleed memory.

Will update my findings too. :slight_smile:

Why should a pencil trace not be reliable?
What are you expecting to happen with it?

For starters, the graphite is practically in dust form. What’s stopping dust from scattering?

I tried the line and glue. It’s not easy to get the line just right, they were either too resistive (too little) or too conductive (too much). After a while I got them to reset in 1 second, put some glue on top - and works like a charm finally.

I kinda like this method. Really easy mod once you get hold on how much to draw.

Hm I must have been lucky to get it on my first try. I think the trick might be to use a light pencil, draw a little and then test it before drawing any more.

What glue did you use btw pulsar?

I think any glue will hold the trace well, but I used PVA glue anyway (white glue) because it’s still a little flexible when dried. On top of my head I just think it would hold better during flashlight movements :slight_smile:

I used 2B pencil. At one time I fully shorted the cap when I fully covered the top of cap with pencil marks, so the mode was stuck on high. So that should be avoided. Not a problem though, a quick rub with the hand on the cap and you get to start over fresh.

I think two back and forth light stroke would do the trick, making sure the cap ends are fully connected with the pencil trace.

The pencil trick worked beautifully! I now have a couple of 3xAAA cheapo lights that I can actually use!

At first I botched it by using too broad a line on top of a greasy cap (it was a bit greasy from the manufacturer, I guess). It became 1-mode only. So then I erased the mess with a slimmed down Q-tip and a drop of 90% isopropyl. I sharpened the pencil to a fine point on a matchbook striker. My second try = success!

Thanks meteorxs!

I have succesfuly used the pencil too. It took me few attempts to draw just enough in order to reset the modes in aprox. one second. Other modes are accesible with quick half click. Very nice. At same time I’ve changed led to a bit nicer tint C3.

Anybody any picture with their pencil trace...even just for the records?