Looking to upgrade bulb for diving strobe/light

I have a diving strobe/light combo. Stobe on one end, light on the other. It runs on two AA batteries. What is the best (bright & reliable) bulb I can use for the light end. It presently runs on a regular Xenon flashlight bulb. Thanks for your suggestions.

EHM said:

I have a diving strobe/light combo. Stobe on one end, light on the other. It runs on two AA batteries. What is the best (bright & reliable) bulb I can use for the light end. It presently runs on a regular Xenon flashlight bulb. Thanks for your suggestions.

Click to expand...

No one can answer without knowing what bulb you have in there already.

But no 3volt incandescent bulb is ever going to give you a decent amount of light.

EHM said:

I have a diving strobe/light combo. Stobe on one end, light on the other. It runs on two AA batteries. What is the best (bright & reliable) bulb I can use for the light end. It presently runs on a regular Xenon flashlight bulb. Thanks for your suggestions.

Click to expand...

You might be better off getting a separate flashlight. just attach a strobe to yourself somewhere?
here is an example, I own a similar light, great LED and it uses long life rechargeable li-ion batteries: http://www.ebay.com/itm/350788866808

Since it's a regular flashlight bulb, the fact that it's a dive light is irrelevant to the conversation. You'll probably get much better response if you post in a regular flashlight forum instead of the diving forum, where there are lots more people still using bulbs like this.

Oh, and once you've seen the specs and output of an LED light, you'll never want to use that Xenon again!

jeremiahbarrar said:

You might be better off getting a separate flashlight. just attach a strobe to yourself somewhere?
here is an example, I own a similar light, great LED and it uses long life rechargeable li-ion batteries: http://www.ebay.com/itm/350788866808

Click to expand...

I agree you could get a light that would knock your socks off for not much money, compared to what you are using now, especially if you're willing to go a little bigger.

There are many versions of this light around, with different battery configurations and different LEDs, names, and body colors. The one linked above uses a rechargeable Lithium Ion battery (not included). I know there are some that use 4AA cells. Also, prices range from around $6.00 to over $30.00, so be careful.

If you want a name brand, Princeton Tek makes a number of lights for under $25 that would please you. Even their 2AAA 'AMP' model would outperform what you have now. They make 4AAA and 4AA models, but I haven't seen any 2AA models.

FYI, most lights now specify output in lumens. Most brand names don't exaggerate much, but most of the cheapos do. Some claim double the actual output, or even more. What you have now is probably 7-10 lumens with fresh batteries, though it could be as high as 20 lm or as low as 5.

I'd back the Princeton Tek AMP 1L any day. I recently did an entire night dive with it and it worked great. Output is only 45 lumens with 2AAA, roughly what you get from a small 4AA xenon light, however it will burn a claimed 72 hours. It has a removable cone that can transform it into a beacon/strobe(always on). Retail $17.99 USD. I always carry one as a backup light because of its extremely small size.

DIWdiver said:

Since it's a regular flashlight bulb, the fact that it's a dive light is irrelevant to the conversation. You'll probably get much better response if you post in a regular flashlight forum instead of the diving forum, where there are lots more people still using bulbs like this.

Oh, and once you've seen the specs and output of an LED light, you'll never want to use that Xenon again!

Click to expand...

I agree. I did not initially post in the dive light forum. I assume I was "moderated here". I am not looking for a dive light. I already have a Dive Rite LED Lux 4 as primary and two LED Intova Novas as backups. I'm just trying to improve my ARC Firefly which I use as a strobe. But I always try to make the equipment I dive with perform better if possible. The strobe (at one end) is adequate but the flashlight (at the other end) is marginal at best. I am trying to find out if I can replace the Xenon bulb by something better that can run on 2AA cells.

Are you sure you didn't initially post here? Usually when the mods move a thread, it gets marked as such, in both the new and original forums.

Anyway, if you found the right forum, this question is probably already answered. Unfortunately, it looks like you're not going to get the answer you want here.

I don't think you can direct drive an LED (a white one, at least) very well from 2AA. There just isn't enough voltage. You can get some light out of it, but you can't push it to anything close to its capabilities. That means you need some sort of boost driver, and you will NOT find that in a bulb. It might be that your best bet is to try to find a brighter incan bulb. The ROP guys do that a lot with MAG lights. ROP originally meant "roar of the Pelican" which referred to installing a high-power bulb from Pelican, which was not intended to be used in a small light like the MAG, into a MAG or similar light.

An idea could perhaps be to use lithium batteries in the size of an AA battery. That will give you the extra voltage and also more capacity.
These batteries are also known as 14500 batteries.

Thank you for your replies. I will try to find the proper forum. Are 14500 batteries different from regular lithium batteries i.e. Energizer ultimate lithium?

I guess the energizers are not rechargeable?
14500 lithium ion batteries are also available in rechargeable batteries (e.g. on DX, but also others).

The Energizer is 1.5V (or maybe 1.6) non-rechargeable, while a 14500 is 3.7V rechargeable.

Ok thanks. Is the capacity of a 14500 also greater ? Anyone knows about the bulb below?

http://www.superbrightleds.com/moreinfo/b-series/1-watt-flashlight-bulb/372/

No, the capacity of the 14500 is considerably less than an AA cell. Since the voltage is higher, the total energy is pretty similar.

Not knowing anything about it except what I see in the link, I'd say that bulb is should work nicely if you use two 14500 cells. Keep in mind that the extra voltage will probably fry your strobe.

If you want to use the AA cells, do a google search on "bright PR-2 bulb". There are several vendors selling them to work with 2 alkaline cells. Looks like I was wrong about finding a bulb with driver built in.

DIWdiver said:

No, the capacity of the 14500 is considerably less than an AA cell. Since the voltage is higher, the total energy is pretty similar.

Click to expand...

AA alkaline 2000 mAh * 1.5V nominal = 3 W/h
AA NiMH 2500 mAh * 1.2V nominal = 3 W/h
AA lithium 2800 mAh * 1.5V nominal = 4.2W/h
14500 840 mAh * 3.7V nominal = 3.1 W/h


I would not say that the capacity is significantly less with 14500 than with an AA battery. It is a bit lower than lithium non-rechargeables, but it is higher capacity than typical NiMH for sure, and many alkalines also.

The mAh rating is significantly lower, but that does not mean capacity is lower...watt-hours is a much better illustration of actual capacity, rather than just the mAh rating.

Thank you all for your replies. I will try a 1W PR 2 and stick with the 1.5v lithium not to risk burning my strobe.

Generally, when we talk about capacity, we're talking mAh, or Ah, unless it's specifically stated that we're talking about energy density, because we are generally talking about comparing cells of the same voltage. Ergo my statement that the capacity is less, but the total energy is similar.

DIWdiver said:

Generally, when we talk about capacity, we're talking mAh, or Ah, unless it's specifically stated that we're talking about energy density, because we are generally talking about comparing cells of the same voltage. Ergo my statement that the capacity is less, but the total energy is similar.

Click to expand...

This can lead to confusion. I have read several threads where people think because 14500s have a lower amp-hour rating, they deliver much less total energy. I do not think we should assume that everyone knows the distinction. A mAh rating is useful for comparing only two cells of the same chemistry (and therefore voltage). I.e., a 3400 mAh 18650 has around four times the energy (watt-hours) of a 840 mAh 14500. But you cannot compare AA to lithium ion without further explanation. A 2500 mAh NiMH AA has only about 1/4 the energy of a 3400 mAh 18650, even though the amp-hour rating is 2/3 of the larger cell.

To me, capacity is a functional definition...what is the light (or other device) capable of doing, and for how long, with a given cell inserted. Therefore capacity is synonymous with total energy, and not a separate thing. Even if you disagree with that definition, it is best to include units, and to remove the potential for misunderstanding. This is all I was trying to do in my post.