Thanks for testing Richard, very good to know i will scratch the sinkpad 2 based triple option of my list and just use the good old noctigons instead
And hank, i read the research you posted & yes over 500nm seems to be no problem for melanopsin, nice that means we can use the whole green spectrum also and potentially make much nicer looking after dark lights.
But i have to say i really enjoy dimming down the red/amber ledstrips lower & lower when it gets closer to bed, it really give that going to bed in the glow of embers feel & it feels very natural & a pleasant way to end the day.
Cajampa, see http://ursula.chem.yale.edu/~batista/publications/ShivaJACS.pdf — a few years old, I haven’t read all the citing papers to see what’s newer. There’s no specific number applicable to everyone (or every species, for that matter, they’re comparing mice, squid, people, cows …).
“λmax” I think refers to the peak, and there’d be a decreasing sensitivity above and below wherever the peak is, so yeah, it could well go into that 500-and-above range.
I’m trying a few of the PC-lime emitters at night now to see if they make us feel wakeful or not. I’d guess it’s going to vary with age and each person.
I was looking to get a FET driver for a JAX-MTG2 host I never got around to assembling and I wonder if it’s possible to get the 22mm FET driver with ToyKeeper’s BLF EE A6 firmware and then make things more challenging by being able to run it in H-M-L with memory disabled?
Yes we could do that. Right now I just have the FET 22mm, but I have some prototype 22mm + 7135 on the way also if you wanted to wait a few weeks. That said, we can have the same functionality with just the FET, just without as low of a moonlight mode.
Ok, i missed that they where peaks, so it could be very possible be some effects higher up then. Ok back to considering 550nm a good safe limit again then
The Protecting the Melatonin Rhythm through Circadian Healthy Light Exposure - PMC had an interesting test on a blind man “fig .8” where they tested 555nm and could found no at least claimed effect on melatonine production. But wonder how they produced an exact 555nm light? Maybe a diffused laser or a filter or something.
To bad there is so little available human tests, it should be very easy to test melatonine level & production to the end of the sleep cycle under various light frequencys, maybe not so easy to construct a lot of various peaked light sources though. But somewhere in the 500-550nm range, it probably is and as you say it probably varies from individual to individual anyway.
RMM any idea when you will be getting some more Nanjg 101-AK-A1 drivers in?
Wanting to build a green and/or red UF-T20 to hunt with. Bought those drivers and LEDs from you before and they are working good.
If you are not going to be getting them any time soon, would the 1.52A 17mm driver you have listed on eBay work as good?
That UF-T20, do I understand right that the C8 pill will fit in it? I'd like to be able to swap red, green, and white LEDs into the same host as needed.
I have a question concerning the use of low vf LEDs like the 219C and 71235 drivers, I don’t have clear understanding of how these drivers deals with the volt differences.
I want to build a triple nichia 219C with a 12x7135 driver, if I run it in med mode with a high drain cell and the LED remains with a low voltage, does the driver “consume” the excess power? And what happens in the case of a fet driver when the vF and battery V is about 0.8V difference?
It will still be about 7-10 days. Yes, that driver will work. It is just the qlite with 4 chips removed (you can order it from the site for less money). I am not sure about the C8 pills, since there are so many different ones.
The 7135 is a linear regulator, so it operates under the same principal as any other linear regulator, which is that it is basically a variable resistor.
So, at 100% PWM the difference in voltage needed for the given output current is burned off as heat. The greater the difference, the more heat is generated. With a 1S cell situation and a 3V LED, the difference isn't generally that large, so the efficiency isn't that bad, especially since the cells sag voltage a bit. At a medium 33% mode, you are just pulsing the 100% power, so the dissipation isn't that bad. If you were using an analog dimming, where you vary the constant current amount, then the losses would be quite high on the lower modes.
With the FET driver only the FET and driver resistances are doing anything. Usually, you get about 0.005-0.010 ohms of resistance through a good FET driver, depending on the current draw, FET gate voltage, temperature, etc. The batteries usually sag enough under load to keep the current within the safe zone for most LEDs on a DTP. The 219C will pull a ton of amps with an FET driver, but the LED can handle a ton of amps so it works.
Thanks for the heads up on price. I saw the removal chip add/remove option, but didn't pay enough attention to the prices.
I misplaced my main light (Solarforce L2N) somewhere and haven't been able to find it for about a week, going to order some parts to build another. It'll probably reappear as soon as I get the new one put together, but never hurts to have a spare (or three), right? Said last year that I was going to try the T20 and never did, figure since I'm ordering now is as good a time as any.
Memory is simple, but changing the mode order isn’t trivial. I think the simplest way to change it would be to reverse the actions of short and medium press, and make long-press reset to the last/highest mode instead of the first. That way, it still uses in L-to-H order internally for LVP and turbo step-down. But I may be forgetting other areas where it has hardcoded assumptions which could cause issues.
However, the code I’m working on now allows either mode order, among other things. It doesn’t care about mode order since it uses a completely separate mechanism for LVP/turbo/thermal adjustments. The catch is it doesn’t fit on a tiny13, so it needs a tiny25 or bigger.
I couldn’t tell a tiny13 from a tiny25 if my life depended on it. I imagine a tiny25 adds as many problems as it resolves if past experiences hold true. Assuming the chip is bigger because of the bigger number, would I have to get a board designed around a tiny25 with different traces etc or can a tiny25 be plopped in place of a tiny 13?
Next week for three days (Tuesday morning through Thursday night) there will be a sale on FET+7135 drivers with the BLF A6 firmware. The pricing will be as follows:
Well I guess I won't be placing an order soon. My light showed up today so I don't need to build a replacement. Still want one of those T20s but was reminded that auto insurance payment is due this weekend, so that's gotta come first. No car = no money to spend on components. After payday I'll see if I can swing it.
So what's the advantage of FET drivers over Qlite driver?
I've got a dedomed XM-L2 glued to a P60 pill that I plan to play with. Was going to get a qlite with guppy drive just to play around with the menu and mode options, since I've never used firmware built like that. Wandering if I should get one of these FET drivers to put on it instead?
FET = Direct Drive/Maximum Current/Maximum Output. To get this, you sacrifice runtime. It also means a LOT of heat, so only use FET in a well-heatsinked host. P60s tend to have a poor thermal path, so I would not recommend using a FET driver. The Qlite is a good option…
I imagine a tiny25 adds as many problems as it resolves if past experiences hold true. Assuming the chip is bigger because of the bigger number, would I have to get a board designed around a tiny25 with different traces etc or can a tiny25 be plopped in place of a tiny 13?