{problems exposed} JETBeam Jet-II Mk3

[CandleFranky]

I write this posting, because I was asked via PM about the JET-II Mk3. I think, this information could be useful for some flashoholics -->

I have the JETBeam Jet-II Mk3 since a few days. I've got it from hkequipment for $54 plus $1 insured shipping. Nice deal ... or not?

The JB MK3 (OP) has almost a throw like a Dereelight CL1H. It even outperforms JETBeams mini-thrower, the JET-I PRO (SMO) - with no problems. Sounds good?

Yessss, BUT --> If you drive this flashlight on max for ~3 minutes on AW RCA123, it gets hot and ... out. I assume, that the over-current protection of the AW cell kicks in. I've tested it with a primary CR123A. There is no over-current protection, perhaps because of this the light began to flicker after a few minutes.

If I switch the flashlight off for a short moment, the problem is gone - until the next fail a few seconds later. I would assume that the JETBeam Jet-II Mk3 draws to much current from the AW RCA123 and when the light gets hot, it perhaps draws even more current - until the cell protection kicks in.

Any other ideas?


By the way: This is my posting 300!!! :twothumbs

 

[kramer5150]

is it designed to run off 4.2V from RCR123 cells?
If its only designed for 3V operation (primaries) that could be your problem.

 

[CandleFranky]

is it designed to run off 4.2V from RCR123 cells? If its only designed for 3V operation (primaries) that could be your problem.

Look here --> Input Voltage: 0.7-4.2V

 

[kramer5150]

oops... I didn't research beyond the ebay link.
Does it perform better with primary cells?

Lets see what other more experienced members have to say.

 

[Crenshaw]

Candle you seem to have been nit picking alot these past few days, small details on brands....:shrug: actually i just dont really like the title, problems exposed implies that jetbeam deliberately hid information, and tried to cheat you.

anyway, it seems jetbeam does have issues with efficiency, thier Jet1-pro had a very ineffcient medium, thier Jet-u would get very very hot on 10440 within a few seconds, etc.So dont think its fairly unusual what you experiencing.

It is also entirely possible that you got a bad unit, and maybe its shorting out somewhere? or something, i only own a jet-u..but yep..title.


Crenshaw

 

[CandleFranky]

It is also entirely possible that you got a bad unit, and maybe its shorting out somewhere? or something, i only own a jet-u..but yep..title.

I don't believe I've got a bad unit, because I've asked hkequipment for a quick check and ... these JETBeam Jet-II Mk3 problems are not completely new at CPF, I've read about it before.

My JET-I Pro has an inefficient driver regarding its medium mode. But otherwise this is a great flashlight. And I seldom use medium modes. The JETBeam Jet-II Mk3 is an impressive light too, BUT buyers should be informed, that serious problems exist, at least in the MK3 version when using max mode.

 

[Jay T]

What do you expect, It's a Jetbeam! They have some little driver issues with all of their lights.

Look at the review, the last few posts.
http://www.candlepowerforums.com/vb/showthread.php?t=181257&page=4

At first the lights was quite dim. Jetbeam then reworked the driver. For over a month it has been known that the light POUNDS the battery very hard. The max discharge rate for these cells is 1.5A this thing will draw 2A +.

 

[CandleFranky]

For over a month it has been known that the light POUNDS the battery very hard. The max discharge rate for these cells is 1.5A this thing will draw 2A +.

Crenshaw, do you listen?
That explains why the JETBeam Jet-II Mk3 is equally bright as a Dereelight CL1H Q5. :devil:

 

[CandleFranky]

In the meanwhile, I have investigated the mystery a little bit: It seems that the driver of the Jet-II Mk3 is designed for higher voltage, which means it prefers a voltage over 3.8V, the more the better up to 4.2V.

Because with every voltage drop, this flashlight sucks more current, and finally drives the AWs cells into over-current protection. It gets worse with 3.0V CR123A primaries. With it, the JetBeam quickly gets hot even on low mode. No matter if you are using regular or advanced mode.

Who can call this a real flashlight? This is at most a nice prototype of something what will perhaps be a flashlight after some weeks of proper debugging. :naughty:

 

[nanotech17]

you actually got the V2 which is very bright but gets hot very fast.
i have the V1 and not as bright as V2 but no heat problems,and you must remember that too much heat might damage your lovely AW cell overtime (you may PM AW and he will gladly explain to you)
to me JB MK3 V2 is not really a good investment with this kind of issue.
my 0.2 cents

 

[CandleFranky]

you actually got the V2 which is very bright but gets hot very fast ... to me JB MK3 V2 is not really a good investment with this kind of issue. my 0.2 cents

Exactly, thank you for your estimation. That was my thought behind opening this "{problems exposed}" thread as a warning for potential buyers. It seems, you can only use this flashlight with freshly charged Li-Ions >3.8V (the more, the better until 4.2V), everything below leads quickly to the production of to much heat.

I wonder about JetBeam. They messed up the driver of the Jet-I Pro and they messed up the driver of Jet-II Mk3 even more. It seems, this company is only behind short term money. They would perhaps construct their lights more seriously, if they had to replace their trashy drivers for free. :thumbsdow

 

[nanotech17]

if you are creative enough,replace the driver with flupic 0.55' or similiar to that and forget about that JB 10 years warranty unless they want to replace it with V1.

 

[CandleFranky]

if you are creative enough,replace the driver with flupic 0.55' or similiar to that and forget about that JB 10 years warranty unless they want to replace it with V1.

Thank you for your advice. But I am not a specialist in electronics. Can you give me more informations about this "flupic"? Will I then have only one fixed mode?

I don't believe that JetBeam is willing to replace ANYTHING. I fear, I can go to hell with my JetBeam 10 years warranty instead. Imagine the costs, if they replace all their trashy drivers around the world! But perhaps I should give it a try. Does anybody know how I can contact JetBeam concerning technical problems?

 

[yalskey]

While we are talking about Jet-II problems... (by the way, why do they call it MK-III? Was there ever a Jet-II MKI or II? And the "Jet-II MKIII V2" come on JetBeam with all the versioning... should V2 just be called MKIV? or actually MKII?)

Anyways, has anyone else been having problems with their click switch on the Jet-II MK3?

Only about every other time I press it does it actually register a click... even though it has the click sound every time I press it. Seems like a flaky click switch. Maybe it's that cheapo plastic retaining ring inside.

Any advice or similar experiences?

P.S. Otherwise, I really like the Jet-II... it has VERY impressive throw for such a small light. Well, I could do without the 181 mode UI however LOL (not sure I've figured it out yet either)

 

[CandleFranky]

Anyways, has anyone else been having problems with their click switch on the Jet-II MK3?

My clicky is okay. Which Jet-II version do you have? It seems not the "Mk3" (they call it not MkIII, but MK3). oo:

 

[yalskey]

I just learned about the V2 version a couple days ago.

I have the original Jet-II MK3. Or at least that's how it's labeled.

What does the Jet-II MK3 V2 Second Edition Director's Cut Revised (Amended) offer more then mine?

 

[CandleFranky]

What does the Jet-II MK3 V2 Second Edition Director's Cut Revised (Amended) offer more then mine?

It is brighter then a Dereelight CL1H and sucks your primaries dry in a few minutes. This might sound funny, but it seems to be the truth.
Has anybody the email-adress from the JETBeam Support? Because I have a 10 years warranty ...

 

[WadeF]

In the meanwhile, I have investigated the mystery a little bit: It seems that the driver of the Jet-II Mk3 is designed for higher voltage, which means it prefers a voltage over 3.8V, the more the better up to 4.2V.

Because with every voltage drop, this flashlight sucks more current, and finally drives the AWs cells into over-current protection. It gets worse with 3.0V CR123A primaries. With it, the JetBeam quickly gets hot even on low mode. No matter if you are using regular or advanced mode.

Sounds like the Dereelight digital pills. They are designed for a max voltage of 4.2, and as the voltage drops they draw more and more current from the 18650 to keep 1.2A of current going to the emitter. I wonder if Jetbeam is basically using the same circuit, but rather than a 18650 to take the current draw, they are hitting a R123, or CR123 with it.

I'd imagine if I put a R123 or CR123 in my Dereelight with a dummy battery as a spacer, the result maybe the same.

Maybe this circuit will work better with Jetbeam's new 18650 light, and they are trying to get by with it in their R123/CR123 size light?

I'm tired of all the issues with Jetbeam, I won't be buying any more until I hear they have sorted out their problems. I have a Jet I-Pro with a inefficient medium mode, and I wasn't happy with the quality of parts in the tail cap for what the light costs.

Jetbeam makes cool looking lights, and has good ideas, but they need to get their S together and put out a better product. There are probably more reliable lights on DX for $20-30.

 

[nanotech17]

try- [email protected]
you must provide the serial number of the falshlight ( there is a card that comes together)

 

[CandleFranky]

try- [email protected]
you must provide the serial number of the falshlight ( there is a card that comes together)

Thank you. My email is on its way. :kiss:
I hope they will help unbureaucratically and send a new driver.

Sounds like the Dereelight digital pills. They are designed for a max voltage of 4.2, and as the voltage drops they draw more and more current from the 18650 to keep 1.2A of current going to the emitter. I wonder if Jetbeam is basically using the same circuit, but rather than a 18650 to take the current draw, they are hitting a R123, or CR123 with it.

I'd imagine if I put a R123 or CR123 in my Dereelight with a dummy battery as a spacer, the result maybe the same.

Maybe this circuit will work better with Jetbeam's new 18650 light, and they are trying to get by with it in their R123/CR123 size light?

WadeF, you are 100% right again.

If you want to deliver the same brightness on 3.8V as on 4.2V, then you have to boost the current. Doing this with 18650s is one thing, doing this with RCR123A is a complete different thing. Ideally you should use primaries (CR123A) with the JETBeam Jet-II, because they have no over-current-protection and doesn't switch off. They perhaps simply instead.