Help identifying + and - on circuit board

[AyeMayanor]

This is the circuit board from a River Rock 1AA that I will be upgrading with an SSC P4. The original emitter snapped off at the leads last month and I finally got the board off of the heat sink, only to discover the absence of black and red wires! I don't expect the new emitter to be here anytime soon (from DX) but I'd like to know which is pos./neg. now so I can be ready.

Please use "that yellow thing" as a point of reference. Should I post a different angle?

Thanks in advance.

 

[LukeA]

What I would do is wait until the SSC shows up and wire it in parallel with the old Lux with opposite polarity so that when you apply power one lights up. That one has the correct polarity That way, you won't risk damage to the board by running it with no load and checking the contacts with a multimeter.

 

[koala]

Yes, please post different angle. Best top down. If possible, remove the glue which is blocking the tracks. The picture you had is too dim, a little more light will help too.

It looks like a Zetex 300 boost circuit. If so try connecting the load to the "yellow thing" It's a tantalum capacitor. The brown/orange line marking on the edge is the positive.

 

[AyeMayanor]

Here is a view from the top:

I know what wiring in parallel means, but not sure how to do it. Do I solder the pieces together? Alligator clips? What do I hook them up to for power?

Have a multimeter...don't know how to use it besides checking batteries.

 

[koala]

The two broken leads corresponding to the silkscreen OUT+ and OUT- is where you should connect your LED. Savvy?

Also, be careful when soldering/connecting the positive lead to the LED, the positive and negative pins on the IC chip is very close, don't bridge them or else you will get a short.

Try old alkaline when testing the circuit, fresh NiMH may burn the circuit tracks if there is a short.

 

[AyeMayanor]

Sounds good! Thanks, both of you.

 

[LukeA]

Here is a view from the top:

I know what wiring in parallel means, but not sure how to do it. Do I solder the pieces together? Alligator clips? What do I hook them up to for power?

Have a multimeter...don't know how to use it besides checking batteries.

Well, you have your definitive answer, but I'll continue with the theory. You could use alligator clips or solder to join the LEDs. To power them in that configuration, just hook whatever would power the light normally to the back of the board.

 

[Stereodude]

Do you have a multimeter? If so check out which of the two leads is connected to the outer ring. That is very likely the negative terminal.

 

[AyeMayanor]

Luke, thanks for clarifying. I figured I should ask and make sure before I make it any worse.

Stereo, I have a multimeter but don't know how to use it besides checking batteries.

Thanks for all the help!

 

[Stereodude]

Your multimeter should have a continuity mode which you can use to determine the connections.