Hello to everybody here... \^L^/

Hello to everybody here... \\^L^/

Hello.. I'm a newby. I have read this board for a few weeks. This is my first post on this Board.

My English may be incorrect sometime. Sorry for inconvenience.

I read some aritcle here and get some idea to make my own converter for modify Mag2AA.

I use a simple one transister converter with efficiency 72%
Non regulate power of light, depending on battery power.
But this gives adventage that very high output 500 mA at load for 60 minutes when use fresh battery and after battery go down power of light decrease use lower power from battery. This can operate full 4 Hr. with 2100 mAh NiMh battey. After this time it can operate in dim mode for 30 minutes. Light enough to use for find something in the dark.




This is it's picture..... OOps...! How to post a picture ????

Re: Hello to everybody here... \\^L^/

Hi NaCl, (or should I say "Salty"? ) /ubbthreads/images/graemlins/tongue.gif /ubbthreads/images/graemlins/grin.gif



The easiest way to post a pic is to host it at ImageShack . /ubbthreads/images/graemlins/wink.gif
Please make sure the pic isn't wider than 800 pixels max.

Re: Hello to everybody here... \\^L^/

Sawadeekap (is that correct?). /ubbthreads/images/graemlins/wink2.gif Hope you have fun & spend lots of money, oops, /ubbthreads/images/graemlins/eek.gif I mean try not to spend too much money here /ubbthreads/images/graemlins/grin.gif

Re: Hello to everybody here... \\^L^/

shameless plug: don't listen to flashlight.. spend money here

In all seriousness.. it's very rewarding to make your own mod so welcome to CPF and have fun making lights. Look in the 'batteries included' forum for circuits, we've just designed a very nice one for an LDO driver, and there are boost, buck ckts in there.. i recommend making a constant current driver it's so nice to have consistent light.

-awr

Re: Hello to everybody here... \\^L^/

Correction for load current, not 500 mA, it is only 430 mA.
500 mA is my prototype in a breadboard but this one in a picture I cannot find an exact value of resister, so, current not same as in my protoboard version.

Operating frquency is 100kHz

Low Vce(sat) high gain high switching speed transistor are inexpensive only 0.20$.

Re: Hello to everybody here... \\^L^/

Re: Hello to everybody here... \\^L^/




This module can operate with one 1.5V cell at load current 350 mA.depend on current setting resistor.

Re: Hello to everybody here... \\^L^/

Left TerraLux, Right my Mod

Re: Hello to everybody here... \\^L^/

Sweet, MiniMiniMag host? /ubbthreads/images/graemlins/naughty.gif
[ QUOTE ]
NaCl This module can operate with one 1.5V cell at load current 350 mA.depend on current setting resistor.

[/ QUOTE ]

Re: Hello to everybody here... \\^L^/

Very nice NaCl! /ubbthreads/images/graemlins/cool.gif

(You can show multiple pics in a post btw. /ubbthreads/images/graemlins/wink.gif )

Re: Hello to everybody here... \\^L^/

Can it run on one AA alkaline & lithium as well? How much would you sell one for?

Re: Hello to everybody here... \\^L^/

ensig : Single cell at high output current give lower efficiency.

flashlight : AA alkaline not yet testing.


It is very hard to build it because it's small size. I use 10 Hrs. to build it

This is prototype and switching waveform at that time.

Re: Hello to everybody here... \\^L^/

Luxeon III(white bin), - Thirteen dollars...,

Low Vce(sat) high gain high switching speed transistor - Twenty Cents...

Lime green mini mag host - Fifteen dollars...

Ten hours of hunch back, burnt fingers with soldering iron, screwed eye looking in to LuxIII - Priceless... /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/thumbsup.gif

Re: Hello to everybody here... \\^L^/

Nice NaCl, and welcome to CPF, why dontcha stay awhile!

Great effort, easy to understand pictures, you're a natural around here!

welcome again,
daloosh

Re: Hello to everybody here... \\^L^/

[ QUOTE ]
koala said:
Luxeon III(white bin), - Thirteen dollars...,

Low Vce(sat) high gain high switching speed transistor - Twenty Cents...

Lime green mini mag host - Fifteen dollars...

Ten hours of hunch back, burnt fingers with soldering iron, screwed eye looking in to LuxIII - Priceless... /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/thumbsup.gif

[/ QUOTE ]

Fair dinkum mate /ubbthreads/images/graemlins/grin.gif

Re: Hello to everybody here... \\^L^/

I found something strange about my circuit, it is unstable.
When I use an ampmmeter to measure input current, it make output current larger than direct circuit connection.
It is about input voltage source impedance, at a little bit high impedance the circuit switching smoothly but at very low impedance the switching pulse become burst.


I know that the NiMH voltage are not change so much along the usage time.
I wonder why it can use as long as 4 hrs. insted of estimated 2.5 hrs.

I try to find why it happen and I found that I put wrong bias resistor. I put 10k insted of 1k !! /ubbthreads/images/graemlins/banghead.gif



Below is official result after circuit correction and some modify for more output current.

Light output measure by PhotoDiode (effective area ~1.5 sqmm)at distance 11 cm.

Re: Hello to everybody here... \\^L^/

i like it

Re: Hello to everybody here... \\^L^/

at 2.4 V input

Current at load ~ 450 mA
Current input ~ 1A
Conversion Efficiency ~ 70 %
NiMH 2100 mAh runtime = 2 Hrs.





at 1.50 V input

Current at load ~ 200 mA
Current input ~ 640 mA