Really basic question

tnforever

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Hello all, this will probably be shouted down by a few people for being such a basic question.

Note first that I did read the threads about bulb testing and figuring out voltage, but I'm still confused.

Basically I have this old emergency light that comes with a flashlight, a fluorescent tube, and an amber signal light. The flashlight bulb, however, is long gone, and the person who owns it *ahem* has no idea what the bulb rating was.

So, I have 3 questions:

1) Aside from taking it apart, or blowing up more bulbs, how can I determine what kind of bulb it uses? The light uses 6 D cells arranged in two columns of three, so I can only presume it's either 4.5v or 9v

2) Is there a way of determining the correct voltage bulb I should use based on the cells? ie I know that 2 cell lights have a nominal voltage of 3v, but should I buy a 3.6v bulb to ensure that it won't blow, or should a 3v bulb be sufficient?

4) Aside from this, I have a ton of crappy $1 lights that are virtually useless, and I want to upgrade them so they'd actually put out some useful light (right now they put out maybe 10 lumens from comparison to my L2D) are there some reasonably priced (I'm not sticking $10 bulbs in a stupid $1 flashlight, prefer it to be not more than a couple bucks) bulbs I can upgrade them with? They're all 2-cell, most are D, I do have 1 that's 2AA. I also have some emergency lights that are 6 cell. This also applies to A couple maglites that I have, which are 2-3 cell, I understand the best are ROP bulbs (without modding), but any other options are welcome.

In all, I understand that this is a pretty far reaching and open ended question, it's just taht most of the threads in the incan forum are pretty hardcore (flashlights pushing 1000 lumens?!) but all I want is a reasonable upgrade of really cheap flashlights to make them serviceable. I would overwhelmingly prefer things to be OTC, shipping really kills when you buy cheap things.
 

asdalton

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Nearly all incandescent flashlights are designed to run on the maximum series voltage of the batteries (9 volts in your case). I would not suspect a series-parallel arrangement (4.5 V) unless the two columns have the + terminals of their batteries pointing in the same direction.

Alkaline-powered lamps are rated somewhat less than their nominal battery voltage -- usually 1.2 V per battery. The reason is that alkaline batteries spend most of their useful life in this voltage range rather than 1.5 V, which the battery delivers only when fresh and under a low current load.
 

mdhammack

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maybe try some of the newer model maglite bulbs for your dollar lights. they have been re-rated I guess you could say and put out a whiter light than the older ones. try one pack and see if it's what you're looking for.
 

tnforever

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Nearly all incandescent flashlights are designed to run on the maximum series voltage of the batteries (9 volts in your case). I would not suspect a series-parallel arrangement (4.5 V) unless the two columns have the + terminals of their batteries pointing in the same direction.

Alkaline-powered lamps are rated somewhat less than their nominal battery voltage -- usually 1.2 V per battery. The reason is that alkaline batteries spend most of their useful life in this voltage range rather than 1.5 V, which the battery delivers only when fresh and under a low current load.

This is probably why the bulbs he tried all blew out then, I think bulbs from 2 or 3 cell lights were used, put it under 9v would mean instant death.

This also explains why one of my cheapo light has a bulb rated 2.4v 0.5A... so by that logic I should look for a 7.2v bulb then? I'm a bit curious about how the amperage rating is made for each bulb for a given voltage, i'm guessin it has something to do with the inherent resistance of the bulb filament?

Also, are there bulbs that will provide a flatter runtime curve? I'm guessing such bulbs MUST be electronically controlled (and thus are expensive)?

maybe try some of the newer model maglite bulbs for your dollar lights. they have been re-rated I guess you could say and put out a whiter light than the older ones. try one pack and see if it's what you're looking for.

Thanks, those are cheap enough that I won't cry over them... as I understand it though, people here prefer ROP bulbs because the bulb shape creates a much nicer beam? Are there similar bulbs that would work on a maglite and can be bought and a B&M? I don't mind putting some cheap incan bulbs in my cheap lights, but would like a better beam pattern from my maglites (or if the price is not too bad, why not for my crappy lights too?).
 
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TorchBoy

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(1) so by that logic I should look for a 7.2v bulb then? (2) I'm a bit curious about how the amperage rating is made for each bulb for a given voltage, i'm guessin it has something to do with the inherent resistance of the bulb filament?

(3) Also, are there bulbs that will provide a flatter runtime curve? (4) I'm guessing such bulbs MUST be electronically controlled (and thus are expensive)?
1. Yes.
2. Yes.
3. Without going to fancy LED drop-ins, no, but you could use rechargeable cells, like an AA NiMH (eg, Eneloop) in a AA-to-D adaptor. NiMH cells have a much flatter output voltage than alkaline cells.
4. You can put in drivers, and many are not particularly expensive, but there's probably no real need if using NiMH cells.
 

tnforever

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1. Yes.
2. Yes.
3. Without going to fancy LED drop-ins, no, but you could use rechargeable cells, like an AA NiMH (eg, Eneloop) in a AA-to-D adaptor. NiMH cells have a much flatter output voltage than alkaline cells.
4. You can put in drivers, and many are not particularly expensive, but there's probably no real need if using NiMH cells.

I will hold off asking for how all the V,I,R and P works until I've refreshed my physics-fu and basic understanding of incan bulbs.

As to your other comments - I do have eneloops, but all are taken up by my LED lights at the moment, since I rarely use these lights (esp the cheapo ones). So that would mean I'd have to get some LSD cells and carriers (I only have 2 from my eneloop kit, and one is missing it's tab... have had to stick a small screw inside to space it... ) But thanks for the help so far.

How do D-cells do compared to an AA LSD in terms of current discharge (for normal flashlight bulbs, ie, the ones I want to use in my lights?) I've seen discharge curves for AA cells, but not alkaline D cells... I might just take up on that suggestion though, and turn one of my lights into a superleggera.

I should note that I do not have a soldering iron (yet).

Speaking of LED, I've seen the master PR LED thread, but the choices really seem limited. I would've thought by now some big manufacturer would've made some multi-Nichia drop ins?

These are just some of the comments I have atm, I'll look up my battery and bulb options more before coming back... again, thanks for the help so far, and still open to particular incan bulbs I can use.
 

Linger

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For your original question, best way is to use a digital multi meter and just check what the voltage is. You can check it from the wiring or at the socket if required.

Yes amps are determined by the bulb, and in your case you'd like .9a if you can find it. In this situation the higher amp rating will be a brighter bulb.

Look for Halogen if possible, or xenon. Krypton will be dullest, all other things being equal.

The diminishing output is a function of the batteries you use. The better the battery... you got it. Pop over to the battery section or Search for a discharge curve of your batteries for a great example. The curve gets steeper as draw increases, so lights with the brightest bulbs may visibly dim over a few minutes as the batteries run down. (Electronically regulated output works by keeping the voltage to the bulb below the batteries available discharge rate)

You could keep an eye out for led PR base drop-ins. Or start modding and wire one up for yourself: if your starting light is $1 you might make something surprising.

beam pattern is partly from bulb, partly from reflector. Bulbs can be frosted, reflectors can be textured. You can do both of these yourself as well.
 

tnforever

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So, I might go out tomorrow and stop by some stores on my way home to check out light bulb options that I might have. Anyone have recommendations for good places to start?

National chains of course, for those who are willing to give more local recommendations I live in the Bay Area.

I know where I can find Mag bulbs quite easily, but I'm more curious about more exotic bulbs... specifically ones that can improve the beam pattern from a maglite.

As for LEDs, I'm sure I'll invest in a Malkoff one of these days (they sound amazing) but for cheapo lights, I'll either want to wire up a Cree and underdrive it (but that's a whole other topic) or wire up some 5mm LEDs, which doesn't sound too appealing, mostly of the awful tint and CRI
 

325addict

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I have similar lanterns, most of the time (if not nearly all) a bulb of 7.2V / 0.5A is used.

DO NOT EXCEED 0.5A!! Otherwise the flimsy plastic reflector will suffer a meltdown :shakehead

Or do you happen to have a really old one, which may have a METAL reflector? Then go ahead and find yourself some nasty good powerful bulb :devil:


Timmo.
 

tnforever

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I have similar lanterns, most of the time (if not nearly all) a bulb of 7.2V / 0.5A is used.

DO NOT EXCEED 0.5A!! Otherwise the flimsy plastic reflector will suffer a meltdown :shakehead

Or do you happen to have a really old one, which may have a METAL reflector? Then go ahead and find yourself some nasty good powerful bulb :devil:


Timmo.

No, I'm quite sure it's a plastic reflector. The overall quality of the light is actually not that great, and I have no idea where it came from either. Thanks for the specific rating. I might be naughty and see if something slightly higher is available :D

Do you think I can get away with a 0.6 or .75A bulb?
 

Linger

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DO NOT EXCEED 0.5A!! Otherwise the flimsy plastic reflector will suffer a meltdown :shakehead
Interesting. I have one 2.4v .9a PR base Philips bulb. I don't know where I got it from (nasty habit of swaping out bulbs in any old PR light with led's and collecting the PR bulbs). I went through the bulbs one day on an incan kick and noticed this little gem. very little gem. It may double the output of another prbase bulb, but winning the race at 2.4v isn't winning much...
anyway, drop-in substitute, it was no hotter than any others, I just noticed it was exceptionally bright and pulled it out to read the stats.
 

tnforever

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Interesting. I have one 2.4v .9a PR base Philips bulb. I don't know where I got it from (nasty habit of swaping out bulbs in any old PR light with led's and collecting the PR bulbs). I went through the bulbs one day on an incan kick and noticed this little gem. very little gem. It may double the output of another prbase bulb, but winning the race at 2.4v isn't winning much...
anyway, drop-in substitute, it was no hotter than any others, I just noticed it was exceptionally bright and pulled it out to read the stats.


Well in my case I think he means don't exceed .5A with a 7.2V, since that's 3.6W, whereas .9A with 2.4V is only ~2.2W

But I've read in a thread somewhere (while doing some incan research) that someone can run 11W on a maglite stock reflector with no problems...

On another note, where do you find Philips flashlight bulbs? The only bulbs I ever see are Maglite, Radioshack... and probably something generic from GE, never really paid attention to flashlight bulbs until about 2 days ago...
 
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Juggernaut

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Ok, just use a stock 6D Maglite replacement bulb for your 6D light. It's like.64 amps and should not melt the reflector "don't take my word on for it". I've melted plastic reflectors with hot wired 6D Maglite bulbs before. Also they say up to the ROP-low "regular driven" will work in a stock Maglite. The ROP- low will melt the reflector a little bit in at over 5 minutes from what I hear. As a side note: I have melted a 99 cent light's reflector in under 30 seconds with the ROP-low:oops:.
 

tnforever

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Hey everyone, thanks for the help so far... so this weekend I went and did some research, and now I have a few new questions.

1) First, I went to a few places (Walmart, Target, Kmart, Home Depot, Fry's, and Radioshack), KPR bulbs are nearly everywhere, and are around a dollar a piece, and either Rayovac or energizer brand.

So, first question, are all KPR bulbs equal (assuming they're the same voltage and amperage rating)?

2) It's more difficult trying to find high voltage (4+ cells) KPR bulbs, any suggestions?

3) Mag Xenon bulbs are about $3 a pop, how much of an improvement are they over standard (PR) or KPR bulbs? For that matter, how much of an improvement is a KPR bulb over a PR bulb?

4) Anyone know whether they have flashlight bulbs at Target/Walmart? I looked in the flashlight section and the light bulb section and didnt notice any.

5) Most importantly, I've only found an HPR53 bulb at Fry's ($7) and a HPR50 bulb at Radioshack ($4), is there any other local place that might sell PR-based Halogen lamps?

6) Finally, I found a Wikipedia article on lamp rerating, are the formulas the same for all kinds of filament lamps, regardless of the gas? I ask mostly because I might undervolt a Halogen light in a 3D light, or run another one in a 6v lantern...

7) One slightly OT question, I don't feel like starting a thread in LED for this. I noticed the high powered LED drop ins for PR are all quite outdated, has anyone made a standard PR one with a Rebel/XR-E/P4 LED?

I'm interested in keeping a lower power LED around for extended run times, but just cant stand the horrible tint and CRI they give (which is why I started the incan thread in the first place, nearly all my lights are LED, even crappy 2-D lights have better color rendition than my LEDs)

Anyway, on a side note, thanks for all the help so far, the suggestions have been really helpful, but I really hope I dont have to order bulbs online.

edit: barring any new info, I find the suggestions in this thread helpful, and will probably mod a few lights based on its suggestions, what do you think of it? I probably won't overdrive lights with only a few cells, as the formula I used seem to shrink useful life of a bulb down to nothing. (BTW, how long are expected life bulbs for PR/KPR/HPR bulbs?)
 
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Linger

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re: are all equal - probably not, but no ideas how to pick the best, or if the differences are significant in any way you could tell.
1)Remember though, vacumm is horrible, krypton is 2nd poorest performer, xenon is better (actually xenon + halogen, brighter but short life), halogen best.
2)I don't by krypton...life is too short for underperforming bulbs.
3)I don't know.try search, I'm sure this has come up before.
6)undervolting may reduce life / performance of the bulb. They are designed to hit certain running temperatures and if they don't they will dim and diminish in output (again, maybe not enough for you to notice a difference: and the undervolted poorly performing bulb may still be a huge improvement on the other options available)
6b) no, see above, all gasses are not equal. Futher, all filaments are not equal. There's a great ROP thread two similarly spec'd bulbs are shown side by side, one rated ~100h another rated ~2000h.
7) yes the available models are very outdated (and **** poor performers. I had one from pre-cpf days and thought the versatility was great, knowing I could put it in any light and run it for hours. Now I see it as dim and blue, overpriced, and I've lent it to my tenants)

8)careful, all led's are not the same. I have high cri emiters for improved contrast and warm tint emiters that are more soothing than incans. If you have crappy leds, think about changing them (or contact teknocowboy's warm tint modding service. Use good led's only: life is too short for bad cri or led's that are off tinted)
 

tnforever

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Ok, first of all I'd like to thank you for all your patience so far.

1) I'm gonna assume you're just giving me a friendly reminder, I'm under the impression that all KPR bulbs are krypton, HPR are halogen, and unmarked ones (just PR) are something else (argon?) I asked that mostly because there were different brands, and my assumption was based on that I saw normal PR (not KPR bulbs) for about half the price of KPR bulbs at Radioshack.

2) Well most of my lights are not lights I'm interested in spending a lot on modding =)

3) I suppose I'll go and get a Xenon bulb for kicks, if nothing else, I've read the smaller profile and different bulb shape should give a better beam.

6) I suppose that is true for Halogens, but I'd think it prolongs bulb life for Krypton bulbs. Well I might try and get a 4v halogen bulb if I still can't find any locally... I wish someone online would do ordinary shipping (USPS) A lot of flashlight vendors ship for $2-3, why don't bulb vendors?

7) Well I have an original MagLED (Lux3), and they do have a real use in that they can give a usable amount of light after the batteries are too low to run a incan bulb (remember my lights are all stock, no 10v 8AA mods for me), but it'd have been great to have someone make a more efficient one with a Cree...

5mm and apparently the Nite-Ize one (the ONLY one available otc) are all horrible.

8) The only drop in LEDs I have are the Maglite ones, all my dedicated LEDs are acceptable, but just dont produce the natural feel of an incan (Neutral LEDs come close though)... I just really wanted to be able to turn a $1 light into a LED light for fun. Being always in need of money like I am, you can see why I'm hesitant on buying too many bulbs for my lights (I'd rather save my money up for a neutral tint light!) I have a WW that I run with a CW and it produces a very nice tint... just waiting for the right opportunity to snap up a neutral white light...

Thanks for all your help so far, everyone!

Ok, lastly, if anyone else knows where I can find Halogen PR bulbs locally I'd appreciate it a lot!
 

Howecollc

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tnforever

Most of the RayOVac, Energizer, or Radio Shack bulbs are going to be spec'd similarly or even less so than the Mag Krypton bulbs; I'd just stick with the Mags for their ease of purchase and higher performance. All of the Mag Kryptons pull .82 amps at spec voltage, while the Mag Xenons pull around .84 amps at spec.

2, 3, and 4 cell Mag Kryptons can be bought in-store at Lowes for $1.57 for a 2 pack. 6 cell Mag Kryptons are available in-store at Tractor Supply Company for $1.99 a 2 pack. Most any of the Mag Krypton or Xenon bulbs are stocked at police supply type stores, and aren't marked up all that much.

Mag Xenon bulbs are going to put out a whiter light, and their central hotspot is going to be smaller and more round than that of a Mag Krypton bulb. Regular PR bulbs are going to put out a more yellow light than a KPR; they're pretty much out-dated.

Low power halogen bulbs are almost never worth the extra money. The Radio Shack HPR50 puts out the exact same light as a 4 cell Mag Krypton, but at 5 times the price. I have one; it's nothing special.

Frosting the glass on bulbs with Armour Etch (etching paste available for $9 at Hobby Lobby) will diffuse the beam and clean up the pattern, at the expense of some throw.

I bought a Nite Ize PR-base LED drop-in to use with an old $2.00 Eveready 2D plastic light I had. Its performance did indeed exceed that of the standard bulb, but considering the $14.00 price tag, it wasn't worth it; I took it back.

For me, the answer to the question of "what to inexpensively do to all of my old 2D lights to make them seem useable after having become spoiled by the output of my Surefires and other higher quality lights" was to switch to lithium batteries for their higher voltage and flatter runtime. I used 2 CR123 cells with a 3 cell Mag Krypton bulb which is now being overdriven to 4.8 volts under load. It pulls .98 amps at 4.8v for 4.7 watts of overdriven output that is the equivalent of somewhere between a 5D and 6D Mag. I frosted the bulb to reduce some of the excessive throw of the reflector. Runtime is about 80 minutes of fairly steady output that diminishes quickly at the end.

Costs are minimal:
-$3.50 for 2 Surefire CR123 cells (Energizers can be bought on-line for $1.40 each at Lighthound)
-$.85 for one 3 cell Mag Krypton bulb (very lightly frosted)
-cut to length piece of 1/2" foam pipe insulation
-$.50 at TSC for a 3/8" x 2" carriage bolt with two 7/16" (or 1/2") washers and five 3/8" nuts to fill the gap between batteries and tail-spring

the guts
DSCF3154.jpg



very lightly frosted (almost splotchy) bulb
DSCF3118.jpg
 
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