*BLF LT1 Lantern Project) (updated Nov,17,2020)

What should I tell Sofirn as they mention you told them not to

I’m not bothered myself, I can add solder for the ones I sell but it means every review of lumen output is now wrong.

How many lumens approx is 3 AMC’s?

You really checked those pads with a DMM that they are not connected?

It seems that’s a new driver revision with 4 0 Ohm resistors on it if you look closer

Well, that answers that.

Thanks for the input Lexel.

For those who have the latest version: Is the USB-C charging working correct?

I see the resistors in that pic now, i was not aware that they added those.

at least there should be 0 Ohm, if they put 10Mohm there we got a problem

As Lexel says, the latest LT1 driver should have 0Ω resistors connecting AMCs 4 & 5 as standard. You can check that with a multimeter - you should see a short-circuit between the ‘4’ contacts, and another short-circuit between the ‘5’ contacts, even though they’re not soldered.

If any of you have a new-model LT1 and a multimeter, please try it and let us know for sure :slight_smile:

The 0Ω resistors make it easier for Sofirn to manufacture and do quality control, because they’re less prone to human error compared to manually soldering contacts with a soldering iron.

If you want more output from your LT1, you still need to solder the ‘6’ contacts together yourself. If you want still more output, you need to solder the ‘7’ contacts together as well.

If you want less output, you have to unsolder the 0Ω resistors next to the ‘5’ contacts. If you want still less output, you have to unsolder the 0Ω resistors next to the ‘4’ contacts as well.

If you change your mind afterwards, you can restore higher output by soldering the ‘4’ contacts together again, and then the ‘5’ contacts together again. You don’t have to worry about saving the 0Ω resistors, so it’s not a problem if you destroy them when you unsolder them.

The new driver also includes USB-C charging resistors to make it compatible with USB-C to USB-C charging.

If any of you get a new-model LT1 and have a USB-C to USB-C charging setup, please try it and let us know whether it works :slight_smile:

They could be 10k ohm resistors and probably work, but like Lexel said 10 Meg ohm would to be a problem.

If you don’t want to or are not able to solder across the pads, a #2 pencil lead across the gap between the pads and on the pads works well also. Easy to remove with an eraser too.

Revised driver

- Does not matter what combination of AMC pads 4, 5, 6 and 7 are closed.

- Added location for 0 ohm resistors so manual soldering of pads 4 and 5 is not needed.

- Added 2 resistors to allow a USB-C charger to work with the LT1.

  • This last piece should be tested before starting a full run.

I believe that what this means is that 4 & 5 and don’t need to be soldered as before and if you want less output then you can unsolder the resistors. You can close 6 and/or 7 (either with solder or pencil lead) to get more output but unlike prior driver versions it doesn’t matter if 7 is done but not 6. Before 6 had to be closed if you also wanted 7 closed.

Is there still a coupon for lt1?

I just watched Matts video and when I used his Canadian amazon link it gave me a discount right away. I tried the code but the code said it was invalid however I did get a 27.00 discount right away. I got the lantern + batteries. Matts video is linked on the first post

Yes. Will send it via private message.

Could i also have a coupon please?

Will you send it to me too please?

Yes, I was told it is 0 Ω

after watching Matt’s video i ordered one. (used his link/code) thanks Matt! :beer:
glad to support your channel. i also let ads run for all your videos.

our power has been going out more and more frequently here. this is just what everything i want in a light.

will the current version (third run (version2?) work with a 1A wall charger? wasn’t the earlier one with a trim POT adjustable?
i have an external charger (Zanflare C4) but would prefer using my crappy 1A charger with magnetic connector
to save wear on the connector, threads, and batteries which are button top Sammy 35E.

i hope this is the case. perhaps lost in translation? DBSAR’s video :+1: shows that 5 FETs seems to be the sweet spot for efficiency, brightness, and temps.
them saying 6 and 7 are ‘closed’ makes me think they are enabled. in electronics ‘closed’ means connected, and ‘open’ mean broken/disconnected.

but i’m sure most you know that. :stuck_out_tongue:

can’t wait to get my hands on this.
/richard

I have tested the LT1 and it works with most 1 amp wall chargers, though some of the lower amp chargers get quite warm. (as the LT1 is shipped factory default as 1.5 amp charge rate) the factory 5-chips per-channel is a good balance of output & run times for most uses, while the two extra chips can be bridged to add some output lumens increase with a slightly lowered run times.

thank you sir. i have a ‘1.5A’ iPad wannabe charger that shits the bed if going over 1A. metered with a UNI-T UT658.
thanks for confirming the 5-chips.

can’t wait to get your wonderful creation in my hands.
cheers

/richard

As DBSAR says, many 1A chargers will still work with the stock LT1 (even though the LT1 expects 1.5A), but the charger may get very warm.

If that worries you - or the charger refuses to work at all - there is a way to reduce the LT1’s charging current, which DBSAR actually added to the original specification for people with small solar panels and low-powered chargers to use.

First a photo of the driver:

The trim pot doesn’t do anything in a stock lantern - it’s only there for modding. I think it was meant for auxiliary LEDs.

However, if you look below the ‘L’ in “BLF” in the driver photo, you’ll see the word “charge” in white. There’s a solder blob to the lower right of the ‘e’ in “charge”.

If you have a soldering iron, you can melt the solder and break that connection. This will set the LT1’s built-in charging controller to 0.75A instead of 1.5A.

If you get a more powerful charger in future, you can set the LT1 back to 1.5A by putting the solder blob back and restoring that connection.