Slow Death mode discontinued in favour of more important design improvements

The Scorpion X12 Ultra

Revision 1

250 lumens for 24 hours from a 3 X 18650 cell pack!

The design has just been revised. The slow death mode has been dumped due to perceived issues and the lamp redesigned to give even greater efficiency resulting in some fantastic burn times.

250 lumens for 24 hours, beat that!

(Last 2 hours at diminishing output with red warning flashing)

There is a basic issue in producing a lamp with a high maximum output but with efficient lower output levels. Additional to this is the problem of producing a lamp that retains its output on any brightness level, but is a simple buck circuit. Obviously, higher efficiency means longer burn times; this combined with sustainable output means the lamp is suitable for long weekend activities away from recharging facilities. Go back underground the next day and every mode bar Turbo as bright as the day before.

All of the above has been achieved. Four useful output levels with up to 94% efficiency on all but Turbo Mode There are Standard (200 lumens average 94% efficiency), Standard Plus (500 lumens, 94% efficient), High (1000 lumens, 91% efficient) and Turbo (3400 lumens). On low battery the lamp will start to flash red, this indicates approaching shut down.

A further issue with some lamps is tendency to flicker at low outputs, this driver is based on a DC-DC converter and is flicker free.

I will be able to easily produce a custom lamp for anyone who wants lower outputs for say tighter calcited cave systems where the 250 lumens base setting would be too much light. This would be easily achieved by simply increasing the value of the RSense current sense resistor. If effect, this will reduce all the outputs and can be made to order. An example is RSense = 0.05 ohms will give about 180 lumens Standard and Turbo of about 2600 lumens. Normal fitting is 0.04 ohms.

Main points:

• GoPro mounted with full GoPro compatibility

• Average 94% Efficiency on lower 2 modes, 91% on High.

• High sustainability on all outputs. Brightness does not diminish as battery depletes. (Bar Turbo Mode) Diminishing output is a common issue with most buck drivers.

• Up to 3400 lumens max output.

• Blue 4 LED battery meter

• Green super efficient gallium nitride power LED also serves as pilot light, enough light to move about if main circuit fails.

• Single "flick" action toggle switch, non fumble.

• IP 68 - 5 metre submersion (subject to short time frame due to cable joint)

• User friendly 4 modes at a flick, non fumble.

• Lamp will not suddenly go out on depleted battery, A bright red flashing LED alerts the user to the battery state and output will fall

• 4  LEDs, 2 beam and 2 floods, 1/3 of the output shared between 2 floods so heat minimised on each flood LED. Flood failure is most common failure on a lot of lamps

• Weight 230 grams.

• Dedicated 12V 3.5 AH Power bank, 280 grams.

• GoPro helmet bracket included

• Free GoPro accessory pack with lamp. Cycle and tripod mount, extensions etc.

• Other accessories available.

The F_Tech driver utilises an analogue voltage signal to control brightness, rather than the usual Pulse Width Modulation (PWM). If the latter needs explanation, you can read all about it in Wiki. The aforementioned voltage signal is a product of my own design analogue controller that generates 4 output signals.  Problem with off the shelf and cheaper drivers is falling output as the battery goes down, and poor efficiency at lower brightness levels. This is basically what you can expect to get in most Chinese torches and headtorches. The off the shelf buck driver shown in the comparison graph is actually one of the better ones. So how bad are the poor ones? I could say but would probably be disbelieved!

The graph below shows a comparison at high mode, lower ones perform similarly as does the poor quality conventional buck driver shown for comparison. The graph ends at 9.5V which is where mine starts flashing red. Lower modes comparison are worse, the off the shelf can be as bad as 68% while F_Tech averages 94%.  I have compared the high modes as the outputs are similar.

Another issue with the Chinese products are falling output as the battery depletes. Graph below, again at High Mode, makes a comparison between the two.

Connecting the battery to the Scorpion enables a bright green Gallium Nitride emitter pilot and power on light. These are very efficient at low current and underground testing has confirmed that one can easily see ones feet and in front; this would still operate in the event of failure of the main electronics.

The lamp starts flashing red at approx 9.5V (Adjustable) and then continues to burn on standard mode for a couple more hours on falling brightness.

I can customise outputs on demand with lower settings for anyone not wanting as much light.

The new lamp has virtually nothing sourced from the Far East; all electronic and major components are from major western manufacturers. All the electronics are my own design.

 3 cell 12V power bank. Weight 250 grams.

Included accessories, helmet mount, and accessory kit: Cycle and tripod mount and extension bars.

Nice helmet bracket!

Geeky Suff. The F_Tech driver