My Emisar D4 is a “touch” light?

Just wondering if this D4 is worn or like new. Anodizing is non conductive.

Moderator007 it’s very worn it’s my EDC. And I thought of that and that’s the really puzzling part. If I hold the head with one hand, there’s no light, but I can touch the fully anodized round body tube with just the tip of a finger (while still hold the head with the other hand) and the LEDs glow. It’s so weird. But when I lock the light out by unscrewing the tail cap it’s dark always, which does make sense, because the negative part of the battery would then only be touching the spring and PCB and has no way of conducting electricity anywhere else, even if the threads were bare aluminum, because the pcb is just glued in the tail piece. . None of it makes any sense though yet. FYI I’m not suggesting any mystical magical stuff, it’s just odd.

But literally one person can hold the tube, hold my hand with their other hand, and then I can light it up with my other than. The current goes through (at least) two people. But we have to be touching each other or it doesn’t work. I wish I could put videos up.

can anyone else do it without you ?

Yes, it’s not Zach-specific. Just as long at the two hands are connected. My hands or anyone else’s hands and “our” hands connected by holding hands. Lol. It makes me think a “touch” flashlight would be pretty sweet. Like turn it on with two taps and change modes just by touching. Kind of like a touch screen or apples new home button. A button-less flashlight

You’ve clearly got a current leak path somewhere in the head of the flashlight.

Can you post pictures of the negative/ground white wire connection of the driver?

Or ask the manufacturer how to test for a problem so you could get an exchange.

I’m not that Hank

Well I have two more D4s on the way, and I’ve swapped LEDs in this one I don’t know how many times. But isn’t there something with the middle pad on nichias? Like it’s not neutral or something? Does the MCPCB get a charge or what if my positive or negative leads are touching the MCPCB? I haven’t taken the head off yet but I bet that’s something to do with it. Just the symptoms seemed quite odd.

My wife has no capacitance. I converted a lamp for her to a touch lamp. No work at all, touch, grab, 2handed throttle…no work. Bought a factory one, same scenario. Works fine as advertised for me & others. Same for touch screen apps….no workee. Is she an alien?

I don’t see how touching the body and the head could be completing a circuit that should already be completed when you screw the head to the body.

Edit.

I vote for a video.

Touchscreen nichia D4 - YouTube There’s a link on my YouTube channel. I don’t know why it always uploads 240p but you can see what I’m talking about.

Try this, take the tail cap off and lay your finger across the battery and the bottom of the tube.
Does it still light up?

Moderator007, no dice. Just tried that. Doesn’t glow at all. It has to be in the driver cause it doesn’t do it when the tail cap is unscrewed slightly. So it’s like how an e-switch needs a small amount of current to work. Maybe it’s leaking by the e switch. I really have no clue. Interesting though right?

No idea what the problem is, but I’d love to see some video of this.

I put a link a few posts up. I put a video on my YouTube channel. If you watch you can see how the pressure of my hand (surface area of my hand on the light) affects the light output. Still it’s all less than a lumen I would say almost certainly.

And I have to say, normally something like this would bug me like a speck of dust in my reflector—which btw using your tongue really is the best method for cleaning one—it’s actually kind of cool as long as it’s safe. I guess time will tell if it’s safe.

I kind of think there is something touch in the tail cap. And it maybe very small with no more light than its making.
When you stuck your finger on the battery and the tube should be the same as you holding the cap and touch the head.
I just pulled my D4 out to look this over, the tail is always connected.

I’m trying to figure this one out but that’s just strange it acts that way.
Maybe you are just are a good conductor. Too much salt :smiley: .

I have seen this issue before

The only explanation I can give is that the LED- on MCPCB has a grounding or low resiastance(conductive acid flux) to the head part, easily to check with DMM
But the D4S has insulated driver and Tube usually, so there cant be a current flow bypassing the driver
seen on Lights like Convoy L6 going instantly to Turbo when you turn on on Tail switch

so you act as cinductor between head and Tube bypassing the driver

Yeah but think about it. When the batter is in and the cap tightened, the flashlight is energized ready to go. When it’s slightly unscrewed it isn’t, even if the threads were bare aluminum, the negative part of the battery is touching the spring and pcb it’s connected to, nothing else. So it needs to be energized, i.e. have potential, for this to work. I mean I don’t think there’s really anything in the tail spring to go wrong or act anomalously. I don’t know but it’s really freaky doing the two person thing and lighting it up upon touching someone else’s hand.

just watched the video. You should sell that broken D4 to me…