I see, Thanks for the insight⌠So from an expertâs perspective itâs not worth it then? I guess it is easier to work with something you are familiar with. After a few years in this forum the most I can do is still just swapping LEDs.
I can only speak for myself but as Iâm not an expert itâs just so much easier to make my own. I started my driver and firmware development here on BLF without previous knowledge of it before, all with the help of tutorials, the wealth of knowledge and people here that where willing to help. The topic of reading firmware from other MCU types and then debugging them for changes is not something that Iâve seen done here, I think for the same reasons as I stated above⌠But I donât really know, Iâve never actually tried it, maybe itâs not as hard as I think but now Iâm too far down the rabbit hole of making my own to bother.
I really need to learn how to make PCBs. Iâd be fine using the same circuits others develop, but if I could adapt them to a PCB suitable to the particular host I want, that would be the dream.
I would want to learn that, too. First thing I would do is to shrink a MT09R/GT4 driver from 46mm to 30mm.
Itâs a good time to try kicad, they released the 6th version recently and it has nice improvements over 5.
Have anyone taken apart the dual channel D4V2? Whatâs the difference besides the driver and PCB?
I think those are only differences.
Does anyone know the copper plate thickness of the FC11 and FC12?
I asked Hank for dual channel driver and copper board because I was going to reflow emitters anyway. He said itâs too different. I wonder what else was changed.
At least my single channel and dual channel KR4âs seem identical. I have also bought dual channel driver and 2 channel pcb from him separately for my projects, so I donât know why he didnât sell them to you.
Maybe you misunderstood each other because I had no problem when making weird requests to him.
Edit : I should have quoted, the comment I was replying to has been deleted.
Sorry about that deletion. I clarified with him, I just spent $5000 HKD ($650 USD) with his wholeseller in HK too. Itâs definitely not money related. Seeing the events happening around the world, I think itâs a good time to spend more money on your favourite material things before everything shuts down. Evergrande for ex.
Can somebody explain this apparent paradox? Tungsten or halogen bulb is quite inefficient in terms of converting electrical energy in to light. But ironically, none of the flashlights using them as bulbs ever worried about having huge heat sink or thermal regulation. However, all the of the high power LED bulbs need to dissipate excess heat even though for tungsten or halogen, the emitted light was just by product of the filament burning!
Itâs very simple, filament bulbs are made of metal and glass and can withstand extremely high temperatures.
Leds are electronic components, diodes made of silicone, plastic and phosphor. They do not like extreme heat. They need to stay at lower temperatures to last a long time.
Maybe your asking about the heatsinks? Most all older flashlights using bulbs also used low power lead acid batteries that did not draw high amperage. They were all low amperage and relatively dim compared to led. They also didnât have complicated electronic drivers, they typically had an on/off switch. So if they got too hot you simply turned the light off.
Modern led flashlights using lithium ion batteries can draw way higher amps (100+ watts). Older bulb style flashlights typically drew 2.5 watts. Maybe a bit higher? No where near modern flashlight wattage. Hence, the older flashlights never got very hot. There was no need for heatsinks, especially since the bulbs could easily handle their own heat.
I hope this answered your question.
Good explanation! If I want to get the same amount of lumens as the old incandescent flashlight, there is no need for heat sink then?
Generally, yes⌠because incandescents are horribly inefficient compared to LED. Incans waste so much energy in the form of heat versus photons. You can seriously burn your hand on the head of some high power halogen/xenon incan flashlights.
Yes. For instance, I used to use a 2 D cell Maglite with 1.2v NiMh cells and a 2v bulb to get extra output. When led bulbs came out I was able to get even more lumens and batteries lasted much longer. The original setup produced no noticeable heat and the led setup probably ran even cooler. Itâs very easy to get more lumens with led. Modern flashlights are many times brighter than older incandescent to the point that they can get hot and need cooling. You can take a modern led flashlight and run it at a lower setting and be brighter than incandescent and it wonât heat up much at all.
My charger does 500mA and shows me the voltage of the battery as it reaches 4.20 I just need a ballpark number e.g. listed 2500 battery, is it really 1200 or is it 2300? That would be enough.
Can I guestimate true capacity of a cell by noting how long does it take to say go from 4.00 to 4.20 in minutes? I am assuming voltage increase is linear and inversely proportional to the battery capacity.
I donât think you can use that method since most li-ion chargers start in constant current mode and finish in constant voltage mode. So it will stay at 4.2v for maybe 20 minutes until the current goes to zero, but the time can vary a lot.
The only way I know is to use a battery charger that shows you the milliamphours as its charging. Since itâs usually measured from 2.5v-2.6v to fully charged, I tend to start around 2.8v-3.0v and if it charges 2300mAh Iâll add a little more and say itâs about 2500mAh. So even using a charger that measures it, is not exact. Itâs only pretty close, assuming the charger model has been tested and shown to measure pretty accurately.