BB500 not regulating, light dim--ground problem?

Hello all,
Wired up my 2D Mag and the R2H is very, very dim so I pulled out the multimeter and at the LED the voltage was 2.8V. The battery voltage was 3.0V so all I am doing is dropping 0.2V. /ubbthreads/images/graemlins/icon15.gif This happens if the V in is at the inductor or the back of the board (I don't have the heatsink in yet and wanted to test it on the star)
I wired it per the instructions and wonder about one connection; the ground to the Luxeon. I have the negative wired to the negative strip on the switch with two wires soldered on. One wire is the negative input to the BB500 board and the other wire goes to the Luxeon LED.
Is it OK to wire the negative lead to the LED straight from the negative on the batteries? If not, were do I get the negative from the BB500? I don't see it labled. I know the Pucks have two wires in and two wires out but the instructions for the BB500 only have three wires. /ubbthreads/images/graemlins/help.gif /ubbthreads/images/graemlins/help.gif
If it supposed to be wired that way, it looks like my BB500 is toast. /ubbthreads/images/graemlins/mecry.gif

I *think*, but I'm not positive, that they (led,bb) share a common ground. The bb will fry if there is no load present (no led hooked up to it). So be carefull. Building that NexStar? That's gonna be a sweat light!

Re: BB500 not regulating, light dim--ground proble

Isaac,
I wired it up thinking it had a common ground (two wires from the switch, one to the Luxeon and the other to the BB500) It was dim so I AIM'ed Wayne Y (he was online and helped me out) It seems that the negative Luxeon wire has to come from the connection on the board. It is the two J6 holes, one wire in from the switch and the other out to the Luxeon. It seems to me that it is electrically the same but Wayne said different.
I switched the wires but it is still dim indicating the BB500 is dead, guess it is time to order another one! I will be going out of town for a week starting Sunday so the project is delayed yet again.
Next time I will wire it the way wayne wants it wired and I will go on the bottom of the board, the positive will be soldered on the gold circle for input. I will then use non-conductive epoxy and put it component face-down on the heatsink for cooling.
Such is the rights of passage in flashlight mods, I will not be denied! BTW, the Nexstar will host a red Luxeon and use the stock reflector. It will be in my case with the Anglelux for entertainment in Iraq or other fun countries. The 2D is a frame mounted light for my bike.

Re: BB500 not regulating, light dim--ground proble

BentheadTX.
there might be some connection loose, like cold solder joint somewhere.
Well, believe it or not, i got cold solder joint on my sammich 5W and the light does not light up with 2AA. I tried it with 4AA and it lit dimmly. But it did not died, yet. Somehow, a bit of tapping or throwing (i am serious) get the solder contact to the sammich. This is all happen everytime whenever i used it and somehow i got this feeling that i prolly got a bad board. So, i dissect it and it actually got killed in the process. /ubbthreads/images/graemlins/frown.gif
well, that is a lesson for me. /ubbthreads/images/graemlins/frown.gif