Roche F6 hacking

Heh :)

There is one trick to those, do not attempt to remove the switch PCB, it's glued in (looks like that Fujik crap). Should already be sealed up well though.

I removed all the resistors and replaced them all with solder on the driver pictured above. I see about a 15% increase in output when comparing side by side with an unmodified version. I cant figure out where to test current on them.

I think I have decided on how to make the indicator LEDs actually useful...

With the stock drivers the indicator doesn't do anything until it turns red, at which point it's already low. It doesn't give you any info you couldn't get some other way like the light being noticeably dim. That's not very useful!

What I'm thinking is to have at least one LED on at all times when the light is on. Say LED1 on until 3.6v, both LEDs on for some as-yet-undetermined third color from 3.6 to 3.3v, and LED2 on below 3.3v. The firmware still has the normal warning flash/rampdown to deal with what happens at the very end. I think it'd be nice to be able to check the indicators and get information about what the actual voltage is at any point.

Any other ideas/suggestions?

Holy crap the stock spring is horrible!

I just compared a battery tube still using the stock spring to one upgraded with the copper disc/new spring, using the same cell & head (25R, F6DD driver, single XPG2 S2 1A). Not dark in here, baseline reading was 4.7 lux.

stock tail spring: 15.2 lux

upgraded spring: 20.1 lux

No changes other than swapping battery tubes. That's shocking!

edit: the triple 219B version is even worse... 24.1 lux vs. 39.9 lux

Is that the purple board goodness right there?

Sure, same board I used before I just finally got the indicators hooked up.

That one has the standard STAR momentary on it, and obviously the code doesn't do anything with the internal pulldown resistors on PB0/PB4. LEDs in that pic are being powered by phantom voltage on those two pins unintentionally.

I think the resistors will be something like 470R for the green, and 220R for red. I first tried both of them with 470R, and the green was WAY brighter than red. The red has a much lower Vf than green, but the green is much brighter (both actual output and apparent - your eyes are more sensitive to the green). To get them sorta balanced when they are both on in the voltage range from 3.6 (where the red one turns on to make yellow) to 3.3 (where the green turns off to go from yellow to red), the red needs a higher drive current. They're totally safe and within specs with those resistors even with pins 3&5 jumpered straight to Vcc (or the PWM at pin 6) and input voltage all the way up at 4.2v. Since red will only be used from 3.6-3v it could get away with an even lower resistor, around 150 or something.

Wow. The stock springs are stealing some of the potential of the driver. The tail spring looks like a simple solid steel spring.

Comfychair, that is really nice! I have what I fear is another impossible fantasy; I would like to put a slow, slightly dim beacon light in a small build. I see the light on my laptop when the computer is in standby mode or something. I don’t remember how to reduce quality and then imbed a YouTube video but here is a link to a 7 second video
http://youtube.com/watch?v=http://youtu.be/wO0Sfldm2Cg Hopefully this is not too big a file.

Do you think it is possible to put a tiny Blue SMD LED in that slot or somewhere on the face of a small triple or quad?

Also have you thought about a little RGB like This for your battery level indicator.

The problem with a continuous beacon/locator thingie, is that the MCU can't run it if the MCU is asleep, and if the MCU isn't asleep the parasitic drain when switched off is too high. But, I don't know squat about what can be done with the code, there may be some other possibility.

I suppose you could always connect the beacon LED with just a simple resistor straight to the battery, current draw can be very very small and still run the little LEDs at a respectable brightness. Of course that would just be a constant on, not flashing, unless you added another component like a 555 timer or something that would be able to do the same things (I'm sure there are more modern alternatives to the 555 by now that are many times smaller and more efficient).

This only needs 3 colors, which you can get with two LEDs. Green for 4.2-3.6v, red+green=yellow for 3.6-3.3v, red for 3.3-3v. At least that's the plan, if I can make them balance correctly. And to control them it doesn't need any variable or PWM output from the MCU pins, they're just on or off. Only one of the available pins is capable of doing a PWM output anyway, but they'll both do simple on/off up to 50mA each which is enough to fry these little LEDs. The total output for all pins combined has a max of 200mA but these indicators with the right resistors should be bright enough at 5mA or less.

  1. I’ve been meaning to point out that a 3mm through-hole bicolor LED might be a good option for putting the indicator wherever you want and making sure that the majority of light makes it out through the pipe/window.
  2. You can sleep an ATtiny and use the watchdog timer to wake it up. attiny sleep timer - Google Search

Changed resistors again, 1K/green & 470/red is still more than bright enough for this. Red could probably go up to the next one in my assortment, 680 ohm, red is a little brighter than the green with 1K/470. 8)

Like wight said… watchdog timer. Sleep 99.9% of the time, wake up for a little blip every second or so, then go back to sleep. It’s already listening for interrupts anyway so it can detect button presses, and the WDT doesn’t add much to its regular sleep mode. Chances are that the standby time will still have to be measured in years, even with the beacon on.

How did you knock the rear stainless plug out without damaging the light? I’m thinking of just adding copper braid to the tail spring.

Very easy to knock the rear plug out (I just did it)

Get one of those removable multiple screwdriver heads take out the screw driver insert (flat tip)

Insert in battery tube…bang battery tube and screwdriver on something flat and solid…doink out comes the plug

Go find the daggum spring that went flying off somewhere else, retrieve the plug that is somewhere else but not as far as the spring

Thanks bud. I want to go the comfychair route and make a copper plate but i’m being lazy. I wonder if soldering copper braid on will do me any good.

THANKS phsinvent and WarHawk-AVG!

Just did the simple mod with a copper braid and the internal resistance seems much better now. :)

Phsinvent, there is also the etsy.com just search your size of copper disk and select the gauge you want.

I use a 1/2" socket and extension to knock the plug out. It's not very tight, it doesn't need to be clamped or anything crazy, just hold the tube in one hand and whack the extension with a screwdriver handle.