Mag Solitaire Mod

A few people have posted various LED-mods on Mag Solitaire---most of them use tiny, low capacity 12V batteries. I am not too satisfied with the results. I want to have something similar to Arc AAA's---

1) use single AAA battery
2) doesn't need to be blindingly bright, but should have enough light to read or walk around with
3) good battery life, at least 5h.
4) fit in Mag Solitaire casing, and use the same twist on and off control
5) non-destructive mods, if possible

After some careful planning, I think one option is to fit a mini booster into the space for the bulb socket, about 6mm diameter and 8mm long.

I was able to build a prototype device using a 3mm Nitcha LED, a transistor, a resistor, and a small transformer/inductor made by winding a few turns of enamel wire on a ferrite core. But the mini booster soon failed after being filled with epoxy glue:-(

A painful troubleshooting revealed that the ferrite core I used was to be blaimed---I used a 3mm section cut out from a longer ferrite core (JW Miller Magnetics, model number FB73-422, 11mm in length and 5mm in outer diameter, ordered from Digi-Key, part number M2308). I realized that this particular ferrite core was designed to be used as a choke in power supply lines, and IT IS CONDUCTIVE!

There is no space to put in any insulating material before winding the enamel wires through the hole, and the conductive nature of the ferrite core means if the insulating enamel coating ever get broken, the ferrite core will short out the wires---in one word, the reliability of the entire booster hangs on a few micrometer thickness of enamel coating!

I am still trying to find other suppliers of the ferrite core---non-conducting ones---and I am surprised to see how difficult it is to find any so small!

Does anybody have spare cores or know where I can get a cheap mail order? (BTW, I live in Canada(/_\)

Any ideas on alternative Solitaire mod are welcome!

Moved to Mod Forum

Pics pics pics!!

Hi,

No one has posted on this thread for awhile, so I'm wondering how you are doing with this project.

Any chance of painting the ferrite core to insulate it? Would that add too much space between the wire and core?

I have recieved a Solitaire for Christmas and I would like to do something with it; like you I'm not so enthused about a 12-V battery with a resistor. You could rig a step-down regulator but I'm guessing you would have less capacity than a lower voltage battery of similar size, stepped up efficiently. Have not done the math, though.

--Tweel, also post as mcd

How about using a spray insulating coating for the ferrite? They make acrlic sprays for insulating high voltage stuff that should work, and give you 2 layers of insulation. Once it's potted, you should be all set.

I haven't touched the the Solitaire project for a while because I still haven't found the correct ferrite core for the inductor.

I thought about covering the conductive core I used before with nailpolish, but I had some trouble keeping the sub-1mm centre hole open, as the paint tends to narrow it down to a level when you can't fit enough wires through the opening any more. Another thing is that the conductive core acts like a one-turn short-circuited loop that will consume energy, and that's unwanted.

For the LED part, initially I planned to use 3mm LEDs so the mod will be reversable. But they are rated only at 2000mcp, a far cry from the 9000+ you can get from a 5mm one. I guess I will drill the Solitaire reflector to accomodate the bigger LED size. This will make the mod non-reversable, but once I have the LED up and running, I will probably never want to revert it back anyway.

Another idea that I thought about was to find a small tailcap switch, take out the entire reflector unit and use the much larger space in the head for the stepping-up converter. This should be easier to build, and mabe 2 or 3 LED's can be squeezed in for more brightness. Does anybody sell tailcap switches that can fit Solitaire?

Tweel, will you keep us updated with your mod ideas?

I would like clarification, becuase I too am prototyping a device that requires a small step up converter. I am a beginner at this, and could use help.

How do you make a dc-dc converter using an LED, a transistor, a resistor, and a small transformer/inductor? Do you not need some sort of switching circuit?

Here guys, this website has the answers:

Satcure Single Transistor Single Cell LED Circuit

Thanks