OK so it appears that different USB cables make a difference to the voltage supplied to the PAW and it’s subsequent reliability, but just how much? I decided to do a test;
My power supply is a 4s 4500mAh LiPo into a DC 12v 24v 40v to 5v USB Step-Down Power Supply Module, one of these
http://www.ebay.co.uk/itm/111473997718 (falcoguy also has one of these). The output of the PSU is 5.2v (which under the PAW Load drops to 5.14v). I have 2 cables, the white high quality 97cm cable for a Samsung phone, and the black 50cm JuicEbitz cable recommended by Lee.
Powering up the PAW and have it fully running I took voltage readings from the Pi header. The under load 5v output was a steady 4.37v!!! A significant drop. I then swapped over the USB connection to use the JuicEbitz cable….. and the under load running voltage was a steady 4.99v, almost perfect, and a 0.62v improvement with the only variable being the USB cable itself!
I repeated this test with all 3 PAW units I have and got exactly the same results.
'nuff said!