Having recently played around with an experimental lamp for which I still have to perceive a practical use, there has been a bit of a payback in the form of some useful ideas to incorporate into the MagnumStar, I have now given up the quest for more lumens.
My thinking is a lamp with better cosmetic appeal, easier to produce, and with more useful features as well as enhanced reliability.
MagnumStar Mk 7
In essence it’s the same as the previous, except that I have completely dumped the rotating Oldham switch and moved everything into a slightly larger side box. This has given a diversity of advantages as follows:
1/ No moving parts inside the lamp to snag on loose wiring etc. Less chance of short circuits as well.
2/ Only 2 possible water ingress points, the front seal and cable gland. Front seal is 5mm neoprene, cable gland is silicone sealed.
3/ More interior room, less chance of electronic components put under tension, plus more front space. To this end I have been able to now include three XPG emitters rather than the previous two, better matching the 12V input voltage.
4/ The front of the lamp looks a lot tidier inside
Another design improvement from the experimental lamp is the detachable plug XPG module that fits onto a lug through which passes the mounting screw for the LED module. This mounts 3 emitters.
The battery is still a 10 ampere hour, 12 cell, 4 in parallel X 3 in series belt mount pack, but I have dumped the built in voltmeter. No matter how hard I try I cannot make this waterproof, my own lamp got through 3 of them.
Switching is by 2 X double throw toggle switches with waterproof covers mounted in the side box. No 1 is beams or floods, change mode by flicking on and off. No 2 switch is XPG floods or Emergency Light.
Awareness of the ease with which these could be accidentally switched such as in a car boot has caused me to fit a green ‘power on’ LED in the side box, there is also a red low battery warning. The beauty of mounting it here is that switching to full power will cause the maximum voltage drop across the battery, so doing this and holding say a wet glove to the side of the head will enable the user to perceive whether or not the red light has come on. This is like having a more sophisticated fuel gauge, I will even include a guide to battery levels relative to the red light plus different power settings. Aren’t simple things wonderful?
Here are the new power settings
There are 3 XM-Ls in series behind the same small reflectors as the old MagnumStar and driven from the same basic driver as used in the Trigon to a maximum current of 2.75 amps to give 2625 lumens.
There is another 3 series bare XM-Ls, but with the driver being outputting 2.75 amps same as the beams, plus 3 bare XP-Gs at about 900 mA to give about 940 lumens, total 3565 lumens of flood, or the 940 lumens of flood in addition to the beams.
Standard beam remains the same at about 160 lumens
Emergency lights are now 3 X 5mm LEDs which is the new design following problems with the old.
Finally I have moved a bit further in what is to me the Holy Grail with the MagnumStar, actually managed to reduce the weight. It’s not much more now than the first Trigons, just over 300 grams. This has been achieved by using thinner copper in the LED module. Also the side box now has no metal cable glands.
The cable to the lamp is PVC coated multi core and is solvent welded into the side box. The Oldham cable to the battery is retained by a plastic Oldham cable secure. Water ingress is not an issue as the side box is potted. Simple.
Anyone who wants more detail will find pictures etc over on mine-explorer, a haven for the lunatic fringe of lamp building.
:lol:
My avatar is a poor likeness.