Yngwie 17 Report post Posted February 27, 2008 Gday all. I am making a light gantry and bought the following LED's from Jaycar as a light source ZD0190 and used a 12 V 500 mA power pack with a 270 OHM resistor on all 4 Led's and yet only 2 LED's would light up simultaneously. I tried the other 2 together and they worked ok too. Is 270 OHM to much resistance? Also, if I am connecting start lights to my parallel cable using a laptop as a computer, what resistance should I be using for these (same spec LED's as above but green, orange and red) Thanks in advance Quote Share this post Link to post Share on other sites
dangermouse 95 Report post Posted February 27, 2008 I don't know a lot aobut electronics - but I am pretty sure I went for a 220 ohm resitor for my 6 volt powerpack - I think I bought 500 something for the 12 volt the lights worked (I only had 2) but was having trouble with sensors on that set up so left it and got my original set up working again... so not sure if 270 would be too much resistance - the guy at Jaycar helped me work out which resistors I needed. cheers DM Quote Share this post Link to post Share on other sites