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Thread: Another M*gCharger 5761, but why

  1. #1
    Flashaholic* Northern Lights's Avatar
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    Default Another M*gCharger 5761, but why

    I just built another MC 5761 but why would I? I can make most D and C lights now with charging jacks that are more convenient than the rechargeable MC.


    Because of the reflector, this is what it can do:
    2,272 foot throw from my MagCharger!
    It is the reflector, the reflector is different and provides a great deal of throw.

    So I built up my old, almost 27 or 30 year old MC with a parallel NiMh pack. Worked great at first but many CPF experts will tell you the parallel NiMh pack is doomed as it will not repsond correctly to a charger. I killed two packs but they had 5400 mAh that is nearly an hour of run time at almost 900 torch lumens. I could use a multitude of NiMh combinations or protected lithium cells; we are only talking about 30 minutes run time, then...

    KD introduced 5 Ah protected D lithium Ion cells and this should again give me about an hour run time. Turns out the cells are overrated or defective, at least something is wrong with them and they will not handle the load of the 5761 and the protection shuts them down.
    The problems are discussed here:
    Protected D Li-ion 5Ah $22 Shipped each

    So I pulled off the protection and made a pack with Batteryspace.com PCBs
    http://www.batteryspace.com/index.as...S&Category=711

    http://www.batteryspace.com/index.as...OD&ProdID=2774

    With these PCBs you can series charge because they provide the balancing circuit for the 7.4V smart charger which I got at BS also. I left the charger cradle as is so I can also plug in a regular MC but I connected the Smart Charger to the pins too and that way I can choose which charging source to use.



    I built my own ceramic socket although the regular socket with some ceramic blanket or mica shield works fine.

    Ceramic Mag Chager G4 and G6.35 socket- DIY now picts!

    I took the wrap off the D cells and found that the cells were unprotected cells already wrapped and the protection put on and then re-wrapped. I used the bottom plate and connecting leads and just took off the old PCB. I ran new leads off the top and wrapped the cells into a pack using Kapton tape. Then I took the PCB and trimmed it down with the Dremel as it is bigger than it needs to be. I took a 3/4 inch PVC pipe coupler and grooved it for the PCB, put on a Plexiglass top plate and put is ontop of the battery pack. It took up the space exactly to match the original 6V dimentsions. I did change to a Mag spring that had less tension than the one that came with the light.

    First picture show the raw materials, the spacer with the fues gets replaced, I kept the fuse however.


    This is it jus ready to slide together, camera broke but you get the idea:
    <; )}}}}>< I fish therfore I am... pic links: '03,'07,'08

  2. #2
    Flashaholic* missionaryman's Avatar
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    Default Re: Another M*gCharger 5761, but why

    Looks like someone finally found a use for these useless cells.
    What kind of run time are you getting and how many amps are they holding up with the 5761?
    "Let your light shine" - it's the one commandment we all obey...

  3. #3
    Flashaholic* Northern Lights's Avatar
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    Default Re: Another M*gCharger 5761, but why

    I did not measure Vbulb yet, but it definately is brighter than my A123 5761 on litho smo reflector and 256mm aspheric lens. Throws great.
    Now only if the batteries will hold up?
    <; )}}}}>< I fish therfore I am... pic links: '03,'07,'08

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    Flashaholic* Northern Lights's Avatar
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    Default Re: Another M*gCharger 5761, but why

    Quote Originally Posted by missionaryman View Post
    Looks like someone finally found a use for these useless cells.
    What kind of run time are you getting and how many amps are they holding up with the 5761?
    Maybe I am just lucky, I resurected the thread because I found this to be true.

    I walk 3.5 miles before sun up. It gives me a chance to test all my collection for practicality.

    This MC runs 65 minutes until the bulb is a glowing ember like a cake candle just blown out.

    5761 are rated at 5 amps however I have tested them to vary bethween 4 to 5 amps, usually just under 5.

    That calculates to about 5000 mAh for the cells, just what they are rated.

    But you notice I threw away the OEM PC boards and use the Batteryspace boards.

    Nevertheless, one hour from a high output, about 900 torch lumen to begin with for an hour beats the 200 bulb lumens, 130 torch lumens of the original bulb.

    ...and for an hour of usable run time to boot.
    <; )}}}}>< I fish therfore I am... pic links: '03,'07,'08

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