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Darth Enab
12-17-2010, 10:20 PM
I've just ordered my parts from Tim, so I want to do a quick wiring check. Switch is a push-button latching, the resistor for the red P4 is a 1 ohm 2 watt (so it's overdriven by half an ohm), the resistor for the accent LEDs is an 82 ohm, 1/4 watt, and it's being powered by 3 AA NiMHs (which totals up to 3.6 volts). Here it is:

http://img89.imageshack.us/img89/3104/saberwiring.png

I'd also like to know how much runtime this will get. Thanks in advance for looking.

Darth Xusia
12-17-2010, 10:52 PM
Your wiring is wrong. You have your batteries wired in parallel. That will only give you 1.2 Volts.
You will also need a 1.5ohm 2Watt resistor for a red P4, if you wire those batteries in series, which is how they should be. A 1/4Watt resistor will not work.

Darth Enab
12-17-2010, 11:06 PM
1. Your wiring is wrong. You have your batteries wired in parallel. That will only give you 1.2 Volts. 2. You will also need a 1.5ohm 2Watt resistor for a red P4, if you wire those batteries in series, which is how they should be. 3. A 1/4Watt resistor will not work.

1. I meant to wire them in series. They'll be in a 4AA battery pack with a dummy cell. 2. From my (limited) knowledge, half and ohm isn't really much of a difference. 3. The 82 ohm 1/4 watt resistor is for the accent LEDs. Just some silly mistakes I made. :rolleyes:

equinox13
12-18-2010, 03:11 AM
going from 1.2 ohm to 1.5 ohm will be a step of roughly 150-250mA - that's enough to fry your red P4 if you're unlucky. i highly recommend using the 1.5 ohm indicated.

as for the LEDs, i recommend wiring those in parallel instead of series so that they get the same voltage across them instead of half voltage each (which will not drive them if using 3.6V). also, wiring them together with one resister would use a 47 ohm resistor. since Tim doesn't carry any 47 or 51 ohm resistors, i would just wire them with their own 82 ohm resistor.

Darth Enab
12-18-2010, 11:59 AM
1. going from 1.2 ohm to 1.5 ohm will be a step of roughly 150-250mA - that's enough to fry your red P4 if you're unlucky. i highly recommend using the 1.5 ohm indicated.

2. as for the LEDs, i recommend wiring those in parallel instead of series so that they get the same voltage across them instead of half voltage each (which will not drive them if using 3.6V). also, wiring them together with one resister would use a 47 ohm resistor. since Tim doesn't carry any 47 or 51 ohm resistors, i would just wire them with their own 82 ohm resistor.

1. Could I perhaps double-resistor my P4? (Possibly with a 0.5 ohm 2 watt resistor?) The only correct resistors I could find had, like, ten bucks shipping for a 10 cent resistor. 2. Would something like this work?

http://img254.imageshack.us/img254/7640/hopefullythisworks.jpg

dgdve
12-19-2010, 05:53 AM
Terrific actually, just be sure your resistors are correct