Sold/Expired FS: A couple more AAA lux mod

Hi all,

I have made a couple more AAA LS mod (peak body, arc/peak head).
for past sale, please look here:
https://www.candlepowerforums.com/threads/97568

the head basically look like the ones in that other thread. here are the lineup:
http://img398.imageshack.us/my.php?image=p10100016pd.jpg


from left to right
a) Arc black head (anodizing is kinda in good to mint condition) (shipped, forgot to who )
b) Peak head (baylisstic) (awaiting payment)
c) Arc HA natural light head (ericl) (shipped)
d) Arc HA natural dark head (criollo) (shipped)
e) Arc HA natural dark (a bit lighter than d) head (delghi) (shipped)

All head has RXOH 1W Lux, driven by LT3490 350 mA current boost regulator. The head has been sealed on the luxeon side for water tightness. It is no diving light, but i would say it will survive bath time . The reflector has been polished like a mirror by ticey.

this is a typical beamshot against Infinity ultra:
http://img506.imageshack.us/my.php?image=infultravspeakls6pf.jpg

I will include a choice of either peak body lug style or keychain style. Shipping is included in the price.
I stand behind these lights, so if there is any problem, just ship them back (at my cost) and I will either repair, get you another one, or give you a full refund.



these lights basically done. But i am currently waiting for a shipment of O-rings for the head

. Stake your claim, but dont send payment yet. I will ask for payment when the orings ready. If you dont need the oring, i can just ship it right away.



I am asking $65 for each shipped to you in US via USPS mail. International, please pay actual shipping. I accept PP and MO. Post here for priority.
Cash to [email protected]
CC (add 4%) to [email protected]




thanks for looking


[EDIT] WTB a couple Arc AAA Orings (about 7) Let me know if you have some spare to sell. I bought three shipment of orings but none reaches my place (yeah, thats right, dunno why. someone must be hungry of rubber). So pm or post here if you have extra orings for sale. Thanks

Shifd,
Delghi has a wanted post for one of these in this same forum, you might PM him.
I'd jump on one but I already have two.

Do these operate on 1.5v or 4.2v cells? runtimes?

mmm.. let's see I'll take E!

Sengoku:
this operate from 1.2V (rechargeable AAA) or 1.5V (Alkaline). Using liion will probably destroy the ic used.

delghi, you get it. I replied to your pm

I'll take one!

Preference for the lighter looking heads -- reminds me more of the arc aaa premiums.

........

shiftd said:

Sengoku:
this operate from 1.2V (rechargeable AAA) or 1.5V (Alkaline). Using liion will probably destroy the ic used.

delghi, you get it. I replied to your pm

Click to expand...

Hi, I made one of these a couple of months ago. I use mine with a Li-ion. The LT3490 should be OK at this voltage - here is a clip from the data sheet:

The LTC3490 operates with 1 or 2 NiMH or alkaline cells.
It functions as a boost converter with a current sense resistor
providing the control feedback. If the battery voltage
is greater than the required LED compliance, it will cycle
off periodically to maintain the correct average current. It
features a low voltage start-up circuit that will start with an
input voltage of only 1V. Once the drive voltage exceeds
2.3V, the circuit operates from the drive voltage.

Cheers,

Paul

Thank Paul for the info

edit: just tried running it with li-ion. Current draw is about 500 ~600 mA. About the same brightness as with single Alkaline/nimh though.

Hi Guys,

I hate to burst the Li-ion bubble, but..

Yes, the IC will run when the Vin is greater than the LED's Vf, and it will maintain regulation up to the point where Vin <= ~(0.5v + LED-Vf). So, a Li-ion will power the circuit and maintain as close to regulated output as possible.

However, the trade-off is in the efficiency of the circuit. When the Vin exceeds the LED-Vf, the current output is kept as close to 350mA as the circuit can handle while, as shiftd's numbers show, the input current rises dramatically.

The result is that while the circuit is over 90% efficient when Vin <= (LED-Vf - 0.5v), it jumps to being ~50% efficient as soon as the Vin > LED-Vf. That loss in efficiency means a lot of excess heat is being generated in the circuit which must then be dissipated.

This isn't neccessarily a deal breaker though. As long as the circuit itself is closely coupled to the heatsink and is potted with thermal compound or thermal epoxy, it can survive the additional heat for quite some time. Also, with a AAA sized Li-ion, the voltage sag on the Li-ion should be sufficient to minimize the efficiency losses and related heat build-up.

The thing to remember is that this IC is designed to provide 350mA output from a voltage that is well below the safe zone for a discharged Li-ion. So with a 350mAh Li-ion cell, and assuming a worst case 50% efficiency figure, you should not run the light for more than 30 minutes total on the Li-ion without checking and/or recharging the cell.

By the way.. Very nice job on those lights shiftd.

pb

thanks for the explanation, PB

My thought exactly. while it is ok to run from li-ion, running it too long might cause the light to be too hot. (and it is a waste too =/ )

Shiftd,

I'll take one!

I have to agree that this is not the ideal candidate for a Li-ion. The intent of my post was to state that this mod should be safe with a Li-ion.

I just did a quick check with mine - the current while on the Li-ion was about 530mA. And yes, it does heat up rather quickly. I potted my pill in Arctic Silver.

I use this like my ArcAAA, in short durations, so heat buildup isn't really an issue for me. Other than that, it is a good "wow factor" light for showing off.

Cheers,

Paul

Got mine yesterday, thanks to incredible service!

The light is about as good as the service as well.

Nice bright VERY smooth beam. A little wider than I would have guessed, but very nice spot to sidespill.

This will probably be my main EDC from now on.

Nice job..

Did you start with completed heads from Peak, i.e. what did you have to do to get the potted electronics out?

Do you have any pics of your electronics? I.e. how did you build the converters--pcb, or ... ?

Thanks.

I'll take B with a lug style if it's still available.

glad you like it, ericl

Paulr, i bought empty head from peak. Then i have ticey to bore the inside a bit and polish the reflector.
I did not take picture during the modding, since I cannot take good pictures and too messy too. But i did not use pcb, and instead i soldered each components (glad not many to begin with) on top of each other. Maybe when i get a chance, i can take a picture to illustrate what i meant.

Baylisstic, you get it.

I got it this morning in the mail
I have to agree with ericl.. Great service and great light!
Cheers to shiftd!
Thanks again
David

Glad to hear you like it, Delghi
humm, that was fast

not really an update, but I am still waiting for a couple of orings. please see first post for details. let me know if you have some

Sent a PM - I may be interested in "A" depending on the reply to the PM.

woops, sorry but all light are spoken for

forgot to edit first post.
again, sorry