Brighten Up Sofirn BLF LT1 Lantern With A Pencil

Interesting wonder what the LT1 guy here who designed/led the creation of the lamp has too say about this. Should I try this 300 free lumens sounds great!

Nice video for showing how easy it can be. Thanks for sharing.

It was intentional on Lexel’s part. I believe it was a group decision that it would be a nice feature for the number of 7135 regulator chips powering the LED’s on the LT1 be configurable. Each chip provides 350mA of current. 3 of them on each channel are inaccessible to the user and always connected (maximum driver current can be limited to 1050 mA).

2 more are accessible and come pre-bridged from the factory (default maximum driver current is 1750 mA) with either a solder blob or a small resistor. Those can be removed if desired. Although it may seem undesirable to limit the maximum brightness, it also reduces the minimum brightness so you can have a lower moonlight mode, and should very slightly improve the efficiency.

Or the remaining 2 can also be bridged by the user to take the maximum driver current up to 2450 mA. That is what is being shown in this video.

The normal method is to bridge the pads with solder, but because these pads only need to power the signal pin on the 7135 regulator chip, the power level is very low, and ordinary pencil graphite should be conductive enough to work. Note that the graphite for mechanical pencils has wax or plastic in it as a binder for extra strength, and is generally not conductive enough to work.

Source:

It was designed to have that feature. :smiley: originally it was intended with those channels left open as an option to “boost” the LT1 to hither than factory outputs, by bridging the two contacts, which adds more 7135 regulator chips in the output stage. (solder, or a high graphite content pencil.

Yes. That’s great

Not exactly free, reduced runtimes, greater heat.

I’ve soldered mine, but have set ceiling ramp to approximately the original highest brightness.

Double click to turbo will do the full (modified) output, but I don’t like leaving the light unatended in turbo for fear it’ll get hot and fry the LED’s.

You see you need to pay attention and ‘be in the know’ with these cleverly designed lights. Many secrets lie within. It’s pretty cool I’m sitting half way across the world with my LT1 apart on my coffee table unlocking it’s hidden talent with direction straight from the horses mouth! (I don’t mean your a horse). But it’s good, got muh HB pencil & about to do surgery.

[quote=CR888
You see you need to pay attention and ‘be in the know’ with these cleverly designed lights. Many secrets lie within. It’s pretty cool I’m sitting half way across the world with my LT1 apart on my coffee table unlocking it’s hidden talent with direction straight from the horses mouth! (I don’t mean your a horse). But it’s good, got muh HB pencil & about to do surgery.[/quote]

:smiley: :beer: :beer: -We built the LT1 to have a good balance of output and run time with its factory configurations. The extra 7135 chip pencil/solder mod is there for those who want to boost the output a little more in sacrifice of runtime. (keep in mind the head of the LT1 will also get hotter too.

I thought it had thermal regulation?

Nope, the LT1 doesn’t need it and doesn’t have it. The top gets a bit hot but not to the point of being too harmful.

Not even when it’s running on all 8* 7135 chips?

It has 7 7135s which means 2.45A at the head. That’s about 7.5W of power and the LEDs turn some of that power into light. I have a 5W little usb heater with less surface area and its heating plate reaches about 80C when constantly on. The LT1 has more surface area to shed heat and the LEDs (probably?) turn more than 2.5w of that into light.

Ý tưởng tốt. Cảm ơn bạn

Here are the temperature tests i did with the factory and all-enabled chips: >> https://www.youtube.com/watch?v=m2jEtJOjd2c

I’d not seen that one before! Thanks for a great vid!

Is 7*7135 run at lower output more efficient than 5*7135 at full??

7 ~ 7135 is about the same efficiency at roughly 78% output, to the 5 ~ 7135s at full.

Great to know! Thanks again!

I did the pencil trick and noticed a reasonable difference but also it’s hard to tell unless you have a modded one next to a stock one. Worked good. I like my LT1 lantern. Used it tonight loading my truck with nice cut & split Redgum for my fire. Was thinking the other night, given the lt1 battery size/tube is similar to many pop can size lights a decent ‘optional extra’ could be a multi emitter head to convert it into a flashlight. But then again I thought if I had that I’d want an extra body tube!! :person_facepalming: Looking forward to the next generation mini when it comes out.

I’D have to check, but my BLF Q8 tube works with the LT1, or vice versa, so essentially what you wish for does exist!

You’re right that you might as well have the tube too, Good place to store spare cells is in a light!

Good news! I don’t have a Q8 either.