Build yer own "Battery Vampire" with a P60

[M@elstrom]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

How are you driving @2.1V or are you overdriving these LEDs?

You are correct I'm over-supplying them with "the juice" from a depleted SF123a currently measuring 2.91v @ rest, the "turbo" mode measures 2.22v @ the emitter whilst the low-low mode weighs in at about 1.7v (thanks to a 150Ω resistor in the 2 stage tail cap) :thumbsup:

I'd like to make a 2-cell vampire module but getting a resistor in there looks nearly impossible. 6V supply with a 20mA drive current @ 3.2Vf yields a 150ohm resistor.

Replace the positive LED's "leg" with the cut down resistor like Superdave mentions in post #69, if you use a G60 lamp module like kosPap in post #17 you could also opt for a SMD (surface mount resistor) I suppose :thinking:

Not sure how long it will run on that though.

A good while, I was running a 3.1v rated SB blue 5mm LED at 2.83v & 2.65v respectively with good results, there's further relevant details in post #80 of that particular arrangement, also seeing as these emitters are sipping 20mA+ from the capacity of a half depleted cell rated @ 1200mAh+ I'd expect some serious runtime! 😀



EDIT: I getting the feeling I really could justify the purchase of a light meter at this stage (perhaps along with a higher A range DMM)

 

[angelofwar]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

+1 on the light meter! Maybe when I win the lottery...I can't really justify a light meter over $100, casue I don't have every 1 of every Surefire model...Yet...It's really neat to see you guys really building on the initial idea, and making little improvements. It helps to show the simpleness (just through a 5mm in there), and the versatility (adding resistors, etc.) to make it brighter or even run longer.

 

[Search]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

I'm fixing to sell my mint older style G2 and all of my P60 modules with all of the LEDs I bought.

I really liked the idea, but it wasn't enough light for me.

Plus, I'm fixing to go rechargeable and after using up the last few batteries would be stuck :thinking:

 

[M@elstrom]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

+1 on the light meter! Maybe when I win the lottery...I can't really justify a light meter over $100

I was actually going to opt for one of the sub $100 units, like this one HERE I also I believe DX have something suitable in the $24 ~ $30 USD range 😉

I really liked the idea, but it wasn't enough light for me.

Plus, I'm fixing to go rechargeable and after using up the last few batteries would be stuck :thinking:

How much is sufficient for your needs? surely an UB white LED would come close to a useable output? :thinking:



Moving ahead with the runtime query posted by gallonoffuel, I found THIS battery runtime calculator created by CPF's penquissciguy, working with the assumption that a fresh CR123a is 3.2v then 2.9v is a 10% depletion transposing that to potential capacity left from 1200mAh we have *900-1000mAh, hence we should enjoy 50+ hours of runtime off these depleted cells in our battery vampires (single cell application) and 40+ hours for the 2 cell application (lower 85% efficiency factored in for resistored LED drive)

* If somebody who's great with formulas wants to rework my lazy/rough approach please post your more accurate findings :thumbsup:

 

[angelofwar]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

I really liked the idea, but it wasn't enough light for me.

QUOTE]

Then it worked...LOL! I use mine for going into our closet, etc. before bed, or in the morning, getting ready for work. Just enough to see what yer doing...

 

[Search]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

After I posted that I did some more thinking and found a way around it.

My planning was to sell it for a little profit to add towards my non-existent flashlight budget.

Luckily I don't think I'm going to need the extra money so when we move out and have the baby I think I'll probably find way more uses for it. Well, I know I will 🙂

The biggest problem now is I'm using a dead battery from my E1B. It drained the voltage so low that it's barely the amount of light it could be.

When the batteries go out in my 6P or E2DL I will get a higher voltage battery to use in the vampire.

It did work, but for what I've found myself doing since I did the mod, it hasn't had any use but to check how centered the 5mm is 🙂

 

[Kestrel]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

Here's two more beamshots from mine, a re-do of a previous shot to better represent the (very nice) tint, and a second one showing the beam profile.
This has become THE light I use for covert nighttime or early morning missions. I'd guess it's doing about 3 lumens or so. :huh:

 

[M@elstrom]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

Luckily I don't think I'm going to need the extra money so when we move out and have the baby I think I'll probably find way more uses for it. Well, I know I will 🙂

For sure you will... speaking as a fellow parent, I can tell you something low output is absolutely perfect for those "quick cot checks" you'll find both you & your partner conducting (even more so for your first born)

BTW congrat's on the impending family addition! :thumbsup:



Have you got the specifications for that particular 5mm LED Kestral? it's 8,000mcd perhaps? :thinking:

 

[Kestrel]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

Have you got the specifications for that particular 5mm LED Kestrel? it's 8,000mcd perhaps? :thinking:

7000 mcd, viewing angle 30 deg, forward current 25mA, voltage 3.3v (typical), 3.6 (max). It's Radio Shack p/n 276-0017. The best $2 (for a 2-pack) that I've spent for quite a while. I notice that RS has reviews on their website, and a previous purchaser had commented favorably on the warm tint. I guess that a person can get a 13000 mcd 5mm from online sellers, but this is the brightest 5mm that RS stocks.

BTW (if anybody is unsure) no resistor is needed, as I'm certain this could happily handle a new CR123 (I'm currently running a 'used' cell with an unknown previous amount of use). With regards to wanting a dimmer light, this is on the upper end of comfortable for my night-adapted eyes, but I'm happily drawing down this CR123 and maybe a year later it will be ~2 lumens or so. 🙂

 

[M@elstrom]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

Thanks Kestral, I'd imagine these LEDs could handle more than their maximum rated Vf as the 2.1v rated LED I just installed is accepting current happily from a 2.9v cell, but much over a fresh cell might be too much IMHO :thumbsup:



According to this site HERE 7000mcd @ 30 degrees equals about 1.5Lm 😀

 

[gallonoffuel]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

In the spirit of the Vampire and seeing how the RS 276-017 LEDs perform on depleted cells and 2xAA in a minimag, I decided to convert an MN01 lamp from my E1D into a small EDC vampire. Too about 10 minutes and most of that was letting the soldering iron heat up. Beam profile is solid, no hotspot to speak of and a nice circle of even light, and with the acceptable tint that these parts produce. Tada!

 

[angelofwar]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

Nice! I bet you get a better beam with the smaller reflector? Did the 5mm fit right in the slot, or did you have to bore it out any? I'm waiting for one of my MN0X's to bite the dust so I can give this a try. Was it pretty simple to put together? Or does it become evident once you get it apart? Nice set-up! Glad to see the "Vampire Project" expanding!

 

[angelofwar]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

BTW (if anybody is unsure) no resistor is needed, as I'm certain this could happily handle a new CR123 (I'm currently running a 'used' cell with an unknown previous amount of use). With regards to wanting a dimmer light, this is on the upper end of comfortable for my night-adapted eyes, but I'm happily drawing down this CR123 and maybe a year later it will be ~2 lumens or so. 🙂

Hmmm...I know the red one's had small resitors built in (according to the package)...I was afraid to try these on a fresh cell due to the voltage limitations posted on the packaging, but I guess it would drop some under load (even a small one such as this)...but if you say they work, I think I'm gonna give it a try. What would you say the out-put is on a fresh cell? Is it noticeably brighter? Thanks Kestrel! Glad to see soo many people enjoying this thread...never thought it would make it to 5 pages...

 

[gallonoffuel]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

Nice! I bet you get a better beam with the smaller reflector? Did the 5mm fit right in the slot, or did you have to bore it out any? I'm waiting for one of my MN0X's to bite the dust so I can give this a try. Was it pretty simple to put together? Or does it become evident once you get it apart? Nice set-up! Glad to see the "Vampire Project" expanding!

The 5mm pokes out as you see it without boring the plastic MN0X housing. I don't know if any of the beam pattern is being obstructed by the plastic, but I didn't really care in this case. It works fine without any drilling.

The small cathode button at the bottom of the lamp pops out and the leg of the stock lamp is soldered on, which needs to be broken off. The negative leg is also soldered to the outside metal ring, but this came off easier. There is a ton of white chalky potting compound keeping the bulb in and it took me a while to get through it. Once you have 3 pieces in your hand (plastic housing, metal anode ring, metal cathode button) just bend the - leg of the LED 90 degrees so when you snap the anode ring on, it sort of holds the LED in. Solder that in. Then figure out how to cut the + leg and solder that to the button. I cut mine and bent it so it rested on the inside of the metal button, and got my soldering iron good and hot and flowed solder into it from the outside.

It's fairly simple, the hardest part is getting the original bulb of out the LA.

 

[M@elstrom]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

Sweet... now we have "Surefire royalty" being adapted for the 5mm battery vampire approach, really nice work there gallonoffuel could we trouble you for some beamshots? :thumbsup:

 

[angelofwar]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

Sweet... now we have "Surefire royalty" being adapted for the 5mm battery vampire approach, really nice work there gallonoffuel could we trouble you for some beamshots? :thumbsup:

Yes! Beamshots, please! I'd like to comapre it to the other 5mm beamshots, and then be able to better determine the need to frost it or not.

 

[gallonoffuel]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

This shot was taken at a distance of 3 feet. The beam diameter is roughly 24". There is no hotspot to speak of, just a smooth beam of warmish white. I don't know what my camera setting are or how to really set it up. I don't think any dome frosting is necessary.

EDIT: The light was at a slight angle when photographing, hence the smearing of the beam at the top. This doesn't happen if the light is level.

 

[kramer5150]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

Great mod!!
I am smiling ear to ear... I did the entire build using scrap parts from my junk bin!!

Heres what I started with.. some spent primaries, old coin cell keychain light, a blown DX Xenon LA fresh out of the junk pile. Total cost = $0.00😛

At first I soldered the LED too far out. My thinking was that if I placed the emitter die at the same location as the Xenon filament, I'd get the best performance.... WRONG. I just got a big white wall doughnut hole😳

So I pushed the LED back in a little at a time to this point... The result is a nice floody beam, with a very slight doughnut hole thats only visible white wall hunting. Overall brightness is a little brighter than my Fenix E0, about 7-8 Lumens.

T.O.P. host.

In keeping with the Lenser direct drive tradition, this one is up next...

 

[M@elstrom]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

Blue is a great colour (my favourite) but the red 5mm LEDs have a lower Vf allowing for overdriving & longer runtimes on "spent" Lithium primaries 😀

BTW I really wouldn't be "mixing" depleted Lithium cells even for a battery vampire project

 

[kosPap]

Re: *Beamshots-Post #36*Build yer own "Battery Vampire" with a P60

Guys today I started a rutime test of my blikig module just cause....

it uses a blinking white LED from a Dx fauxton...it bliked 148 times in 100 secs...now it is powered by an AW RCR...

time wil tell....