Hey Everybody!
Today I ran into problems finishing a “for a friend” job and it’s suddenly taking all my time. I’ve read every post about long cables, distance, twisted wires, data communication and so on. But my question is, as for everybody, slightly different 
Take a ledstrip, lets say 4 meters of apa102, then 4 meter cable and then 4 meters of ledstrip and so on… so something like this:
ledledledledled--------cable4meters-------ledledledled--------cable4meters-ledledledled------- …
Without the “cable4meters”, all ledsstrips behind each other, everything is working fine but with cable all leds in the second strip start to flicker.
Yes, I inject power before each ledstrip, yes, the data signal is 5v, even dug up and Arduino Uno to be sure. Still, weak data signal.
This is the cable I use: http://nl.rs-online.com/web/p/mains-power-cable/9107790
Usually 5 meters between the Arduino and the leds is no problem.
Is there a way to amplify the signal, data and clock? Should I use other cable, add resistors or would something like http://ltech-led.eu/en/spi/1515-spi-signal-amplifier-2ch.html work?
Or just let them use plain old, white not addressable led strips?
