djpark
Enlightened
After receiving 1/3AAA NiMh batteries from vcal, I was wondering what I could do with them. Then I decided to make a new Arc-AAA head with 8mm white led from ISP and feed these batteries to it.
Since my first Arc-AAA with 8mm white led from ISP is now dismembered to donate the MJ Micro converter to Arc-AA with 8mm white led from ISP, I used a standard Arc-AAA booster board this time. So this time, I replaced the stock Nichia 5mm white with 8mm white from ISP, no other electronic changes.
I believe the regulator IC used in Arc-AAA is rated to give 80mA 5V output from 3V battery input. It would only give about 45mA to led with 1.5V input. The point of this mod is to provide higher input voltage to the booster circuit to allow more output current flow to the led. So with 3.6V input, at least 100mA output to led was expected. Actual current detail below...
Edit: If you enlarge the window, it will display 2 picture across.
3 pcs of 1/3AAA batteries were slightly shorter than the length of AAA battery, so I added a little bit of solder, then it is a perfect length. I made a extender using a plastic tube and screw so they can fit well in the charger. It tooks about 30 minutes to fully charge them in Maha C401-SF charger using slow option.
When the new AAA head was fed with fresh charged 3 NiMh (3.6V) input, it drew about 250mA from the battery initially, but soon stabilized to 210mA. At this time the current flow to led was about 150mA with Vf=3.8V. It went on about 25-30 minutes before falling to moon mode (actually still drawing 100mA producing Vf=2.9V and output close to stock Arc-AAA). Didn't measure further for fear of damaging the batteries.
This is quite a bit of overdrive to the led as well as regulator IC. But with the negative led leg touching the casing, the heat was reasonably transferred out and I presume not much harm to be done. Throughout the time, the casing was noticably warm, but never hot. It is very bright and white compared to the stock AAA and AA-8mm with MC (feeding 80mA to led).
I decided that this is worthy of making permanent, so I poured in some epoxy to the back of the led in the AAA head, so it is waterproof now. I also added some glow powder from vcal with the epoxy, so it glows in the dark after switching it off.
I made some comparison of beam output between stock Arc-AAA-P, Arc-AAA-8mm (3 * 1/3AAA NiMh) and Arc-AA-8mm (MJ MC).
From left, Arc-AAA-P, Arc-AAA-8mm (3 * 1/3AAA NiMh) and Arc-AA-8mm (MJ MC) at 50cm from the wall. A picture speaks louder.
From left, Arc-AAA-P, Arc-AAA-8mm (3 * 1/3AAA NiMh) and Arc-AA-8mm (MJ MC) at 1m from the wall.
Now here comes the interesting part.
Arc-AAA-P and AAA-S in my possession draw about 155mA from a fresh Duracel Ultra AAA battery, and they draw about 120mA from a fresh normal Duracel AAA. (funny!) This new AAA head with 8mm white led draws 200mA from the same Duracel Ultra AAA and 150mA from the same Duracel AAA. Naturally, even running with a single AAA battery, this new head is a lot brighter and whiter than stock AAA-P.
Considering the large variation of the leds, I may be just having a better 8mm led. But it is still contradictory to the statement by PG regarding the efficiency of the 8mm led compared to 5mm Nichia.
Here is comparison beam shots. The left one is stock Arc-AAA-P (left) and Arc-AAA-8mm white (single AAA) with normal (auto) exposure. The right picture is over exposured and it gives views closer to how actually eyes see.
The left is at 50cm from the wall (Arc-AAA-P at left and AAA-8mm at right), and the right is at 1m from the wall.
Thanks for viewing.
-- DJP
Since my first Arc-AAA with 8mm white led from ISP is now dismembered to donate the MJ Micro converter to Arc-AA with 8mm white led from ISP, I used a standard Arc-AAA booster board this time. So this time, I replaced the stock Nichia 5mm white with 8mm white from ISP, no other electronic changes.
I believe the regulator IC used in Arc-AAA is rated to give 80mA 5V output from 3V battery input. It would only give about 45mA to led with 1.5V input. The point of this mod is to provide higher input voltage to the booster circuit to allow more output current flow to the led. So with 3.6V input, at least 100mA output to led was expected. Actual current detail below...
Edit: If you enlarge the window, it will display 2 picture across.
3 pcs of 1/3AAA batteries were slightly shorter than the length of AAA battery, so I added a little bit of solder, then it is a perfect length. I made a extender using a plastic tube and screw so they can fit well in the charger. It tooks about 30 minutes to fully charge them in Maha C401-SF charger using slow option.
When the new AAA head was fed with fresh charged 3 NiMh (3.6V) input, it drew about 250mA from the battery initially, but soon stabilized to 210mA. At this time the current flow to led was about 150mA with Vf=3.8V. It went on about 25-30 minutes before falling to moon mode (actually still drawing 100mA producing Vf=2.9V and output close to stock Arc-AAA). Didn't measure further for fear of damaging the batteries.
This is quite a bit of overdrive to the led as well as regulator IC. But with the negative led leg touching the casing, the heat was reasonably transferred out and I presume not much harm to be done. Throughout the time, the casing was noticably warm, but never hot. It is very bright and white compared to the stock AAA and AA-8mm with MC (feeding 80mA to led).
I decided that this is worthy of making permanent, so I poured in some epoxy to the back of the led in the AAA head, so it is waterproof now. I also added some glow powder from vcal with the epoxy, so it glows in the dark after switching it off.
I made some comparison of beam output between stock Arc-AAA-P, Arc-AAA-8mm (3 * 1/3AAA NiMh) and Arc-AA-8mm (MJ MC).
From left, Arc-AAA-P, Arc-AAA-8mm (3 * 1/3AAA NiMh) and Arc-AA-8mm (MJ MC) at 50cm from the wall. A picture speaks louder.
From left, Arc-AAA-P, Arc-AAA-8mm (3 * 1/3AAA NiMh) and Arc-AA-8mm (MJ MC) at 1m from the wall.
Now here comes the interesting part.
Arc-AAA-P and AAA-S in my possession draw about 155mA from a fresh Duracel Ultra AAA battery, and they draw about 120mA from a fresh normal Duracel AAA. (funny!) This new AAA head with 8mm white led draws 200mA from the same Duracel Ultra AAA and 150mA from the same Duracel AAA. Naturally, even running with a single AAA battery, this new head is a lot brighter and whiter than stock AAA-P.
Considering the large variation of the leds, I may be just having a better 8mm led. But it is still contradictory to the statement by PG regarding the efficiency of the 8mm led compared to 5mm Nichia.
Here is comparison beam shots. The left one is stock Arc-AAA-P (left) and Arc-AAA-8mm white (single AAA) with normal (auto) exposure. The right picture is over exposured and it gives views closer to how actually eyes see.
The left is at 50cm from the wall (Arc-AAA-P at left and AAA-8mm at right), and the right is at 1m from the wall.
Thanks for viewing.
-- DJP
