[1900k edition is in!] WTS: 1900k-5800k 5mm LED 95+ CRI

[rngwn]

I have got a phone call from the shipping comany about the import charges and that the shipment will arrive soon.

I can wrap up to about 10 packs today. Book & Pay before 21:00hrs 22:00hrs GMT+7 for the 3rd round.

[rngwn]

Reinforcement Lot no. 2 has arrived!

[rngwn]

Round 3: Shipped

Chatika vas Paus - RR146459745TH

[rngwn]

I pulled 3 random LEDs from the 2nd batch for spot-check.

Here’s the light (appearance) test on 5500k WB and 2800k WB

https://imgur.com/a/5P4iLzH

[rngwn]

Tracking numbers update:

Phosphor22 - LX054010845TH
e1000 - LX054010831TH
Kame Sennin - RR146459793TH

[djozz]

Received the package of 100.
There will not be a proper review until next tuesday (I will have enough forum chat time but there will be no hands-on cave time possible).

Quick first impression of one random led from the package:
*plenty bright
*very pleasant tint to look at
*very smooth broad beam (60 degrees from specs seem correct)
*edge of the beam a bit warmer than the rest (found it not disturbing)
*at ~20mA, middle of hotspot: 3325K, duv –0.0039, CRI=97.4, R9=88.

Summary so far: great led

[SKV89]

@djozz

*at ~20mA, middle of hotspot: 3325K, duv –0.0039, CRI=97.4, R9=88.

Summary so far: great led :+1:

Wow! Sofirn should get some of these.

[Barkuti]

Many will be waiting for the review djozz. Thanks.

Any 7x emitter honeycomb arrangement host or flashlight out there for these? Hexagonal/honeycomb is the most dense arrangement, I wonder why it doesn't seems to be widely used.

[rngwn]

How about this as a host? It’s 0.5w though, so I don’t know if my LEDs would survive that.

https://www.aliexpress.com/item/32833777655.html?spm=2114.12010612.8148356.12.6afa51e8B6l2WJ

[1stein]

Received! Many thanks.

[DavidEF]

@djozz

Received the package of 100.
There will not be a proper review until next tuesday (I will have enough forum chat time but there will be no hands-on cave time possible).

Quick first impression of one random led from the package:
*plenty bright
*very pleasant tint to look at
*very smooth broad beam (60 degrees from specs seem correct)
*edge of the beam a bit warmer than the rest (found it not disturbing)
*at ~20mA, middle of hotspot: 3325K, duv –0.0039, CRI=97.4, R9=88.

Summary so far: great led :+1:

GREAT! :+1:

I’m really looking forward to seeing the results of your testing.

[contactcr]

Re-posting this old Yuji mod just for ideas:

My first LED swap which didn’t require solder. In fact I only used a screwdriver, wire cutters, and tweezers:

I recently ordered some batteries from Shockli’s aliexpress store and they threw in some freebies with my order. One was this cheapo keychain light. It has a 5mm straw hat LED that is press to activate and has a tiny switch to “lock” it on.

I bent and trimmed the legs of my Yuji 95 CRI 3200K LED

We have light!

I just now am realizing it had 2 stacked CR2016 batteries so I am probably giving this thing way too much voltage? Maybe a 2032 battery would have been more appropriate, who knows. I guess if it dies i’m out 55 cents…

[slowtechstef]

If you still have stock I woukd be interested in 1 pack as well. See the PM.

[DavidEF]

@contactcr

Re-posting this old Yuji mod just for ideas:

My first LED swap which didn’t require solder. In fact I only used a screwdriver, wire cutters, and tweezers:

I recently ordered some batteries from Shockli’s aliexpress store and they threw in some freebies with my order. One was this cheapo keychain light. It has a 5mm straw hat LED that is press to activate and has a tiny switch to “lock” it on.

I bent and trimmed the legs of my Yuji 95 CRI 3200K LED

We have light!

I just now am realizing it had 2 stacked CR2016 batteries so I am probably giving this thing way too much voltage? Maybe a 2032 battery would have been more appropriate, who knows. I guess if it dies i’m out 55 cents…

The CR2016 cells are 1.5V nominal, so two of them would be 3V, which is fine for a white LED.

[contactcr]

@DavidEF

The CR2016 cells are 1.5V nominal, so two of them would be 3V, which is fine for a white LED.

I dont know anything about the cells but when I look at replacement ones on Amazon it says 3V nominal

[DavidEF]

@contactcr

@DavidEF

The CR2016 cells are 1.5V nominal, so two of them would be 3V, which is fine for a white LED.

I dont know anything about the cells but when I look at replacement ones on Amazon it says 3V nominal

Huh. Yeah. I just looked. You’re right. Hmm. Curious thing.

[Kame_Sennin]

@contactcr

I just now am realizing it had 2 stacked CR2016 batteries so I am probably giving this thing way too much voltage? Maybe a 2032 battery would have been more appropriate, who knows. I guess if it dies i’m out 55 cents…

I have used and gifted dozens of these small lights, all the white ones use 2xCR2016 and i have never seen a single one with a fried led.

These coin batteries have a high internal resistance so the voltage drops when you load them with a led.

[Barkuti]

@DavidEF

…

Huh. Yeah. I just looked. You’re right. Hmm. Curious thing.

CR2016 cells are “3V”, but their internal resistance is very high. Thus, 2x in series CR2016 cells drive a 5mm led well.

[rngwn]

That and the fact that you don’t turn that on for a sustained period. Even if you overdrive these LEDs and degrade them way faster than their rated lifespan, you probably won’t notice it.

[iamlucky13]

CR2016 cells are indeed 3V. The “CR” code denotes a lithium manganese dioxide chemistry, nominally 3V.

Alkaline button cells are 1.5V and are given “LR” code. The typical form factor is also fatter and taller than lithium coin cells.

A pair of CR2016 cells shouldn’t be any concern, but because of the low forward voltage on the Yuji’s, they run pretty well on a single CR2032 cell, in my experience.

I haven’t done a controlled test, but I’d expect you would get more stable output and significantly longer runtime out of a single CR2032 compared to a pair of CR2016’s, although you might get higher initial output out of the latter. The massive voltage drop the pair of smaller batteries experience is in part due to a lot of energy being wasted on internal resistance.

Either cell does better at these kinds of loads with intermittent use (a few minutes at a time) than continuous use. It’s surprising how much the voltage recovers when a load was removed in a test HKJ did:

Low current discharge of batteries

Low current discharge of batteries [image] My usual battery tests uses a fairly high discharge current, but in many applications batteries will last for weeks or months with the device on. To get some better data for this I decided to do some low current discharges, i.e. with discharge times up to a few weeks. For this I I will show capacity down to a couple of different voltages. Due to the time involved I can only do it with a few batteries, other brands may be better or worse. …