Smiling Shark SS-5039 1 x AAA size flashlight, modification notes, Now 3 x 7135 with modes, on a BLF Tiny 10 board.

Sweet pill and reflector set up. Is the beam on the left the C8 beam?

It must be a special feeling to use tools that you know were used by your grandfather.

My Deal Alert 5049s arrived. They are very similar to the 5039 and 5038 in shape and finish. The threads match.

The driver is different. No boost, but it appears to regulate the otherwise direct drive current I read the resistor as 51 ohms, yellow brown black gold. (Bad boys rape our young girls, but Violet gives willingly.) That is too high to be in line, so it must control the other thing which looks like a transistor.
I read 0.2 A with half charged Eneloops. Again, the board is cut down from a surplus or large production larger and more complicated one.

Yes, if you look below, the lights are in the picture.

Apparently the three terminal thing is a PNP NPN (p channel?) junction field effect transistor or an old fashioned junction transistor. The resistor is connected from + in to the gate or base. The emitter or whatever is also connected to + in. The collector or whatever (plate) goes to + out. - goes straight through to -. To first approximation, the output current is proportional to the current in the resistor, so it should act electrically like a resistor. I get from battery charge state and tail cap current:
2.66 V 0.22 A 12.0 Ohms
3.14 V 0.28 A 11.2 Ohms
3.21 V 0.31 A 11.5 Ohms
So it starts regulating somewhere around 3 V. The apparent slight increase in effective resistance between the last two might be explained by the drop in voltage of Advanced Lithiums under load.
The obvious mod seems to be a lower value resistor and Lithium primary cells, if the transistor can take it. Or if one wants long run time, it is good as is.
0.22 A at 2.66 V is close to the chart for an XM-L2, so the led has a nice low forward voltage.

Fritz t. Cat wrote:

Yes, if you look below, the lights are in the picture.

OK, so is the light on the left the C8?

jk. Sorry, didn't see them down there. Ever since Ouchyfoot posted that one beam shot, it's an effort to look down.

I hate to say this, but Post 60 went straight over my head. Sounds like something someone with electronic knowledge would understand.

Hooking up one of the Nanjg 102s with broken flange on the core to an SS-5039 led, I get 0.22 A to the led ( at 3.7 V)(?). With two half charged Eneloops I read 0.43 A at the led tail (?), compared to 0.22 at the tail of the 5049 with these cells. So, at least with low cell voltages, the boost driver gives a substantial increase in current, assuming the 5039 led does not have lower forward voltage than the 5049 led and that the meter averages the fluctuating current in a reasonable way. On the other hand the reduced duty factor must decrease the led’s efficiency and clearly uses the stored charge less efficiently.

Added: I am not even sure what this means myself now. I will have to repeat the measurement before deciding to use a boot driver.

I don’t have extensive knowledge of circuits, but yes of course most people won’t understand post 60. On the other hand some people on here can correct me if I am wrong.
It is a current limiting driver, like 7135 drivers. But instead of limiting the current to n x 350 ma., it limits it to the input voltage divided by 11 Ohms. (I suppose that is the best one can do with two simple components.) Like 7135 drivers, it falls out of regulation at low input voltage, in this case about 3 volts.
The 11 Ohms, if I am correct, comes from the 51 Ohms of the resister divided by the current gain of the transistor.

It would be nice to find a way to put 7135s on a 12 mm. board.

Would this 12mm linear driver pcb by Mattaus work for you? From this thread.

Yes, that looks like an improvement, because of constant current, because we know 7135s can take more voltage drop than that without overheating and because there is mode control. I may try building one, but I have not yet built a surface mount circuit. I guess I can get most of the parts by cannibalising a Nanjg 105c. Swapping resistors with wire leads is easier, more familiar and cheaper for me. I ordered a set of three from Osh Park. I also bought resistors this morning.

If you don't already have some, do yourself a favor and get some solder paste and a hot air gun. Makes reflowing smd's a breeze.

You can get a cheap hot air gun. Mine is as cheap as they come and I have been using it for years on all kinds of stuff. Even autobody mods. I think I'm using this solder paste at the moment. Seems to work good, even for reflowing emitters.

http://www.fasttech.com/products/0/10003546/1261003-chips-repair-tool-soldering-paste-grease

Now it appears that my analysis of the circuit is wrong. With a lower valued resistor I get less current. But I may not have it together right. Even after making jewelry, this thing is little.

In a dozen flashlights, I found 3 or 4 o-rings. I got Burna-N 70 and silicone 1 mm. cross section o-rings from The O-Ring Store, in various sizes. The silicone ones do not fit. They are too weak to be squeezed into such tight spaces and do not stretch any farther than the others do. For the head, 10 mm. inside diameter seems right and matches the ones originally fitted. The tail space is smaller and 8 mm. seems best. 1/2 mm. o-rings are used for watches but do not appear to be easy to get in small quantity.
I have not attempted to waterproof the front. My best idea is wax.

I ordered the paste. The Martian heat ray might take up too much space for the times I would use it, and I am already spending enough. I do appreciate this help in bringing my electronics skills into the 21st century.

Wax, what a novel idea. I have to give that a shot. Seems like it could make threading smoother. I have a multi pack of rubber o-rings, but often I need sizes I don't have.

You'll like the solder paste even with a solder iron. It's just so much easier to control the quantity per joint. It's also thick enough to hold help those little components in place so that all the pieces don't shift around if you jar or bump the circuit board. For some reason, I really enjoy watching the flux boil out of it when heated.

Do you do your soldering under a vented hood or something? I solder outside if the weather is ok. Otherwise, I do it on our kitchen stove. I cover the stove real good and then clean it up real good afterwords. I annt a work bench with a real strong vented hood.

The lube I use most often on threads is good furniture wax, a mixture of bee’s wax, carnauba wax and orange oil. I sometimes use Treewax carnauba based floor wax on doors but have not tried it on flashlights yet. I use a thinner lubricant on threads to clean them up.
My wife has not complained about the smell of fluxes, except when I use my propane torch. There is a common room I could use with a high ceiling.
The tail of one of the lights was not holding its o-ring, even though it is under sized. I got it to stay in place by deepening the groove with a triangle file.
I have not continued testing of the 5049 driver yet. Ordered three more of them though. If all else fails, I can use direct drive again.

I will have to check into the waxes. I don't know anything about any of them.

Dude, I'm no expert, but I think Flux fumes have very bad stuff in them.

I think I found what I did wrong. Under the subheading “Constant current diode” in the Wikipedia article “Current source” it says:
“The simplest constant-current source or sink is formed from one component: a JFET with its gate attached to its source. Once the drain-source voltage reaches a certain minimum value, the JFET enters saturation where current is approximately constant. This configuration is known as a constant-current diode, as it behaves much like a dual to the constant voltage diode (Zener diode) used in simple voltage sources.
Due to the large variability in saturation current of JFETs, it is common to also include a source resistor (shown in the image to the right) which allows the current to be tuned down to a desired value.”
So that must be a PNP (p channel?) JFET and the resister is in line, in the main current path. So I measured the resister I took out, and it is 1 or 2 ohms, all my meter can tell me, not the 51 Ohms I still read coded on it.
So I should try next only a wire there.
I don’t know what the figure to the left is.
Maybe there is another resister coding convention I don’t know, or maybe it changed its value when it was salvaged. I assume most of these things are built with salvaged components from electronics that was sent for re-cycling.
Added: The resistor is not as shown above, but in parallel with the transistor.

With the resistor replaced by a heavy gauge wire, I am getting readings around 0.4 A. With various cells and running down two Eneloops, I get this.

The curvature may be only an artifact due to the internal resistance of “1.5V” lithium cells.
First, this is lower current than I would like but usable.
Second, this shows us how to make drivers even smaller than 12 mm.
Third, Smiling Shark has, at some level, selected leds with unusually low minimum forward voltage for this model. An led from a 5039 made no visible light with the same two cells as the lowest point, and an XP-G drew only 0.06 A. (The light output must go to zero by the point where the voltage reaches the photon energy in electron volts.) Practically, this means it is not clear whether it would improve it to replace the led with a Cree.
Comparing the light output and current shows that at least this example will benefit from a new led.

Got my 2 Smilies today. A SS-5039 and a 49. I like em, especially the texture of the tubes. Nichia 119 definitely going in at least one of them. Light out put isn't too bad on Eneloops. I may keep the stock driver. Although, I will try to read this whole thread and see if it has any info on modding the driver up just a hair. I'll stick with Ni-Mh though.

Thanks Fritz :)

Two AAAs work better with low V forward, so I used a red XP-E. I read 1.1 A on the bench. Assembled: 1.4 A at 2.65 V, without the tail spring. This shows that a 2 x 1.5 V configuration is good for red light, but raises the question of whether it is still in its primitive form of regulation or whether I have shorted out the transistor.