My LT1 is due to arrive Monday. As others have noted, Amazon tracking doesn’t keep up with this once it hits the USA but usps tracking picks up the slack.
Is anyone else’s stuck in a Chicago Limbo? Mines been “in transit” for the past week from Chicago to my states processing facility. Probably customs checked, even though it was already processed through. Post Master is doing an investigation on Monday, as they’re also confused.
I’ll try.
The LEDs produce light when current is passed through them. The LT1 has two sets of LEDs, Warm White (WW) and Neutral White (NW).
The LT1 has seven current regulator chips in parallel with each set of LEDs, 7 for the NW LEDs, and 7 for the WW LEDs. In the design of the LT1, 3 of these driver chips are always connected. The other 4 have the driver control signal brought out to a set of pads, one set for WW and one set for NW. These pads have numbers next to them, 7, 6, 5, and the last set has both 4 and 3 next to it. I don’t know why the 3 is there, as there is no option to connect or disconnect driver 3. For the remainder of this I will refer to the pads with 4 and 3 near it simply as 4.
The LT1 should come from the factory with the pads 4 and 5 soldered together. This configuration produces roughly 600 lumens maximum if I recall correctly. The way the board is designed, the pads at 4 must be connected for the remaining pad connections to be effective. The connections are all in series. I don’t understand why it was designed this way, that may change of future. If your LT1 came with pads 4 and 5 connected, you are all set. If not, then connecting both is recommended. Methods of connection will be discussed below.
If you want more light from your LT1, you can connect pads 6 (one for NW, one for WW). If you want even more light, then connect pads 7. If you connect the pads 7 without 6, you will not get any more light, pads 6 must be connected for the connection at pads 7 to be effective. This is because the connections were made in series for reasons I don’t understand.
There are two methods I know that are effective at making these connections. One is solder, presumably with a soldering iron. The other is to use a pencil and fill in the space between the pads with graphite. As mentioned above, the connection being made is the control line for the driver. Very little current flows through this connection, and the graphite provides enough of a connection for the signal to get all the way to the driver. I have experimented with making the connection at pads 6 and verified by measuring the current drawn from the batteries that making this connection with a #2 pencil is effective. Someone asked what hardness of pencil. I just used one in a drawer at home. Just fill in the space between the pads with graphite. The advantages of using a pencil to make this connection include being able to remove the connection with an eraser (verified in testing), as well as not requiring special tools.
I hope this helps, if DBSAR chooses he can add this to the first post, that’s the only “sticky” that will happen with this explanation.
Thanks sb. This should be stickied or referenced to in the first post.
Yea thanks sbslider, The front page is very busy. Maybe this sort of information should compiled in new topic that’s easier to parse through.
My button/switch backlight on “low” setting is barely distinguishable. Does this mean my unit is faulty, or does it happen across all units? It’s rather hard to find the button in the dark when the light is on at lower levels. It does come on full brightness after a certain level and you can easily see it.
There are edit levels on button illumination. Low, which you show above. I find this perfect for finding the LT1 in a dark room, but without being an annoyance. High, which is easy to see in a lit room, a flashing mode, and off. You can switch between the four levels with 7 quick clicks from off.
The light comes on to full brightness when the LT1 output is higher than about half full range.
Yeah but the problem is the lower level isn’t really (read: at all) visible to the naked eye (while the light is on at <50% brightness). Can’t find the button in the dark (while the light is on <50%), have to shine another light at it, or spin it around a few times…
Hmmm… I seem to have a fourth mode, lightning flash.
Yes, you are correct, I’ll update my post above.
Ahh, I get it now. I agree, the low button light when the LT1 is on is sort of worthless. Nothing wrong with your unit, just an opportunity for improvement in the firmware. It would be nice to be able to chose button illumination level while on, this could be 7 clicks from on. But I think the current build uses almost all the memory, so I don’t know if there is room for this.
@ sbslider…That was very helpful and plan to connect/bridge with pencil across all options.
Thank you for the very informative post. I’m gonna assume that bridging 6 & 7 will draw more volts resulting in less run time from your batteries? Has anyone assessed what the difference in runtime is?
Not volts. The change allows more current to flow. Each one of the 7135 chips can pass 350 mA (milliamps).
You can do the math and come close to the real life decrease in run time.
Good Job SB…… thanks 
Thanks
Thanks
Just to elaborate a bit on MtnDon’s reply, if you enable both channel 6 drivers, you can expect 5/6 the run time as reported here. If you enable both channel 6 and 7 drivers, then 5/7 what is reported here.
The only downside of enabling more drivers is less ability to get fine tint mixing at very low levels. If you run at one tint all the time, then you SHOULD be able to just run at a lower level of control to get the same lumens. However, in order to do so you would need to add more steps if you used stepped control, or just use the ramp side of output control
Will add it to the OP :+1: Thanks sbslider, good post explaining that.