Is it possible to make a DIY LED splitgrade system?

[tcolgate]

The intrepid head (both the compact and the 4x5) is a straight chain of 56 SK6812. It was me that said "2 wire", that was wrong, there's a 3 pin plug (two different version of the plug at different times). I've not checked which pins are which, though that should be fairly easy to determine poking around with some thin wire and a multimeter (or dismantling the connector maybe).

 

[dkonigs]

@dkonigs Do you already know how the Intrepid panel is controlled by any chance (Pin Out)?

Yeah, others have probably already said all of this, but its 3 wires... +5V, GND, Data.

As far as which is which...
The connector pins, looking into the male side:

• Upper-Left: Red wire, Power (+5V)
• Upper-Right: Black wire, Ground
• Middle: Blue wire, Data

Though to be safe, its probably best to open the back panel of the head and do continuity testing from the PCB all the way to your own wiring to make sure you didn't get something backwards.

It will be. If you look at the video at 22:12 he has the light source open and there's three leads visible, red, black & blue. Those will be easily traced to +V, GND and data, and using a continuity tester you can easily verify which is which on the connector. But...you already knew this, having built your own systems!

Btw, I'm still amazed at how (for lack of a better word) amateurish the hardware on the Intrepid system is. Pot meters for setting filter values, a bog standard Nano clone, a hobby LCD with I2C backpack...this is evidently made by someone with hobby level EE skills. Hey, it works, so that's OK...

Yeah, I recently managed to open up both sides of my Intrepid controller, and I was kinda shocked to see this. Its literally just a carrier board (which might have a few resistors on it) with a bunch of hobby dev-board trinkets soldered onto it.

But hey, I guess it works.

My biggest design nitpick with this is that everything appears to be running straight off the +5V from the wall brick supply, whereas I'd want at least some separation between enlarger head power and logic power. Makes me wonder if the logic ever glitches out because of it, but if it did then someone would have complained by now.

Of course it is cheap, and the head itself (LED choice aside) seems to be decently designed.

The Heiland unit might have better designed electronics, but its just the light source and a lot more expensive.

 

[tcolgate]

My biggest design nitpick with this is that everything appears to be running straight off the +5V from the wall brick supply, whereas I'd want at least some separation between enlarger head power and logic power. Makes me wonder if the logic ever glitches out because of it, but if it did then someone would have complained by now.

I've never seen any glitches running off of the power brick. Trying to run off of the USB connection is another matter, it doesn't like that at all (not that anyone sane would be doing that, it was just annoying to have to switch between the US and the power to test stuff).

 

[koraks]

Trying to run off of the USB connection is another matter

That shouldn't even be possible, but the rudimentary electrical design doesn't block this possibility. When running off of USB, the power for the head all goes through a flimsy SMD diode rated for 500mA or so. What's more, on the PCB, the power to the head is routed over an unnecessarily long and narrow track. Again, it works, evidently, but it's just shoddy design.