G+_Daniel Armstrong Posted March 17, 2013 Share Posted March 17, 2013 I think you should include a mention of proper wire thickness in an episode, I heard something about you having power issues with a Raspberry Pi. I would just like to say that your average cheap USB cable is 28/28 gauge, usually marked as 28 AWG 1 pair, 28 AWG 2 conductors, The pair is the data lines obviously, but 28 for the power and ground wires is just too thin with modern devices. 28 AWG is about .21 ohms per meter, so your basic ~6'/2m cable has about 4 meters round trip, for about .85 ohms total. At that resistance you can't pass the USB spec current of 500mA without too much voltage drop, let alone something like my GS3, which charges to 4.3 volts, hence it is impossible for it to draw a full 1 amp of charge current. For this reason I only buy 24 AWG or better cables now. Link to comment Share on other sites More sharing options...
G+_Sam Zick Posted March 17, 2013 Share Posted March 17, 2013 I learn something new everyday Link to comment Share on other sites More sharing options...
G+_Paul Chepolis Posted March 17, 2013 Share Posted March 17, 2013 Never thought of the issue. Thanks for bringing it to our attention. This is why I admire G+ communities! Link to comment Share on other sites More sharing options...
G+_Daniel Armstrong Posted March 18, 2013 Author Share Posted March 18, 2013 No problem, it is easily overlooked. For instance I have a Blackberry Curve cable that is easily twice as thick as the one that came with the GS3, but is still only 28/28 gauge, IE it is all insulation, minimal copper. As Clara would say "Where's the beef?". Link to comment Share on other sites More sharing options...
G+_Nick Barlow Posted March 19, 2013 Share Posted March 19, 2013 The same thing is valid for all cables. I hate when people say you can't run HDMI runs over 50'. Get a 22awg HDMI cable and you can hit 50' easy. Most packages won't say what the gauge is but you can go to monoprice and they will detail the wire size Link to comment Share on other sites More sharing options...
G+_John Mink Posted March 19, 2013 Share Posted March 19, 2013 Nick Barlow just be careful because when you get into longer cables you introduce other problems....even if the signal is ok power-wise, if the spec isn't expecting cables that long (and I have no idea what HDMI is expecting for max cable length off the top of my head) you can still introduce errors in the clock, timing issues, and so on. Data signals are much more picky than simple DC/AC power! Not saying it never works, or even that you can't pull it off on cheap cable, but that it's something to be aware of...especially when you stay getting hiccups in your transmission. Link to comment Share on other sites More sharing options...
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