Svitac ST-H2 Headlamp modable?

I bought this headlamp from Fasttech the other day, SVITAC ST-H2, for my girlfriend. She’s running a night time, half marathon in August and asked me to find her a nice headlamp 8) Of course, the first thing I did was take it apart… :bigsmile:
(Images are click-able for a larger view, although they are just cell phone pictures)

So the question is, how can I get more output from this thing? It runs off of a single AA (alkaline or Ni-MH, no lithium batteries unfortunately). I see there is one 7135, which I could stack another one on top (if there is enough room for it). Also, the UI is pretty bad; M-H-L-SOS… why someone would need SOS on a headlamp is beyond me :expressionless: So I think I’m going to order a new attiny13a from RMM with a different setup and see if I can swap it out with what looks like a driver controller on the far right side.

What do you guys think?

It’s not totally useless. A couple of fellow Swedish climbers got caught in an avalanche while attempting a climb in Chamonix, France. One made it out of the way, the other was swept down about 300 meters. The guy that made it finally made his way down to his buddy to find him with a totally trashed leg. He put his light on in blinky mode (they only had headlight’s with them) and pointed it towards the hut that they had left before attempting the climb, and went back to attend his buddy. This was noticed and a rescue was initiated. Not saying everyone will be in this kind of situation, and I can’t be sure that the light actually had a SOS mode, but at least now it shouldn’t be beyond you as to why someone might actually find it useful.

There is a lot of components on that board. Do you know what they all do? If not, you might be better off designing a new driver altogether. Otherwise replacing the MCU and not knowing what to do with all the pinouts and chains of components seems to me like it would probably take more time than it would to learn how to make your own replacement drop in driver.

I think you answered your own question. It runs on a single AA, 350mA is about the most you should expect out of it.

Why? It barely has the battery capacity to handle one 7135 let alone more. There isn’t enough heatsinking to handle more than 350 mA anyway.

Answered by Mike C. It’s nice when blinky mode is hidden instead of being a part of the normal mode sequence. However, it is better to have it than not have it at all.

Instead of replacing the component, send the whole driver module to someone who knows what they are doing and see if they can flash the MCU for you.

Actually, does anyone have firmware that would even work for a multi emitter light like this one?

Maybe you should just buy a different headlamp that doesn’t need changes to be usable.

A customer review on Fasttech says it’s pretty bad.

Thanks rojos.

I guess it is very lightweight even more with these:
AAA to AA Size Cell Battery Converters

Looks moddable?

Another review here.

Thanks for the replies guys. Looks like I’m just going to have to leave it stock after all. Yea the PWM isn’t great, but to my untrained eye, it’s useable. I’m going to take it for a run one night and see how it works. Hopefully, once my eyes get adjusted, the light will seem brighter than it actually is. I was looking for the most lightweight headlamp possible, and definitely found one of the top contenders in that arena. I think my urge to tinker with it overshadowed the obvious fact that there is zero heatsinking on this thing. :~

Thanks again guys!