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

I just flashed the anduril.2019-11-29b.blf-lantern.hex on my unit, because it went into kernel panic strobe mode more often than I cared for, and ToyKeeper said this should improve that.

But I used the Emisar pogo pin while holding another wire for the reset pin, and hitting enter on AVRDude with my third hand. :wink: Needless to say that was less than fun.

Does anyone sell the HQ Universal Driver Programming Key already assembled? I don’t have a reflow oven and soldering the pogo pins to the PCB is not my kind of fun either.

I’ve googled the tar out of this and can’t find a US source for any pre-assembled Lexel driver compatible pogo key. TIA for any help!

Yes, indeed the ability to run with no batteries was an accidental, but great usable feature. :+1: The inductor begins to oscillate at high audible frequencies past 6 volts, but at the standard USB 5-volt input its silent. a low cost 12 volt to 5-volt USB adapter fixes the noise issue for anyone wanting to run it directly from 12 volts. I have test run the first production unit i bought for 5 days/24 hours non-stop on mode-3 of the stepped settings using a 5 volt USB wall adapter. it stayed quiet as a mouse. :smiley:

I have a first batch lantern. I get the inductor whine when I have tried it connected to power supply without batteries. Its completely silent on battery power though. I use it every night as a lamp alternative in my office. Works flawlessly. I have charged it fully one (1) time since I received it. Really is a fuel miser in my experience. Can’t thank the team enough! I was on the list for two lanterns. Getting my second one now with code sent by Sofirn. Awesome lanterns!

If we wait, can we put off using our group buy code for when a colored version is released?

Sorry if it’s a repeat. I’ve sifted through the last hundred or two posts and didnt see an answer to the question.

Watch out with buying multiple lanterns with one code as you only get discount for first lantern. I bought two and only had the first one at group buy price. This happen to anyone else?

I too would be interested in purchasing a pre-assembled pogo key if available.

Maukka’s measurements of 355 and 463 lumens (WW and CW) sound kind of low to me; weren’t these supposed to be about 600 lumens? :frowning:

Yes. It happened to me as well.
I messaged Sofirn and explained that and he said it was an error with their code. He has sent me a new code.
My advice is to message Sofirn back directly.

I received my first code and ordered 1 lantern.

Am I correct that I must wait for a 2nd code to order the rest of mine?

I’ve suspected for quite a while that 600 was probably too high. It’s pretty common for amc7135-based drivers to get around 100 lm/W when using medium-CRI LEDs like XP-L HI, and this efficiency goes down when using high-CRI LEDs.

If I understand correctly, my prototype was made before the correct LEDs were sourced, and it probably gets near that common 100 lm/W level. Using some quick napkin math, this would make it…

  • 350 mA * 5 * 3.6 V * 95 lm/W = 598 lm

… which is pretty close to the estimated value of 600 lm.

But with high-CRI LEDs it should be lower. Let’s say 75 lm/W…

  • 350 mA * 5 * 3.6 V * 75 lm/W = 472 lm

… and that’s pretty close to maukka’s measurement of 463 lm.

I think the output was going to be increased by using a somewhat less-opaque diffuser, but for some reason the factory went with a diffuser which was more white and less clear. So the beam is really smooth, but it reduces the total output a bit.

Efficiency could be increased by using a boost or buck driver instead of a linear driver, but that wasn’t within the scope of the project. It’s mostly just an idea for next time, if there is a next time.

463 lm is more than enough for a lantern.
A pleasent high CRI is MUCH more important.

Could someone point me to the driver schematic please ? I am sure i have seen it somewhere (but maybe that wasn't the latest version) but can't find it anymore

Probably, depends on the inductor used.
I think only the ‘open type’ can be glued or potted to stop coil wine. The ‘box’ one’s probably not.
However it’s worth a try ;).

‘Open’ type :

‘Box type’

I’m not a elektro technical guy though.

Just received my lantern! Ordered from amazon.de on november 16 and shipped november 30 according to the tracking details.

Heavier than expected but that’s not a problem for me.
Look and feel is great! Really happy with it. Probably not going to use it in a real camping situation but you will never know :).

The light is nice warm on the warm side, a bit too cold on the cold side. it looks more like 6000K than 5000K to me.
I think I will solder the bridge for all the AMC’s to increase brightness.

Just received my lantern.
Ordered 23/11
Shipped 30/11
Received 4/12

Amazon.de.
:sunglasses:

No harm in doing that, but just a reminder its easy to make the connection with the pencil trick, and even easier to remove the connection if you wish.

Still surprised this works… So the contacts we’re bridging just control the 7135 chips, not carry any current I guess?

Yes, the lines that are open are the control lines for the 7135s. I was surprised it worked also.

I soldered mine as well. Makes quite a noticeable difference. Went from bright to almost to bright to look directly at.

This source seems half the price of one on AliExpress, so thanks. I’m going to order one or two.