Bought a Sodial Single Phase Voltage Transformer Module AC Output Voltage Sensor for Arduino ( from Amazon if you want more infor on these) but I got large glitches on its output that I traced to being caused by my Powerline network adaptors ( not glitches when they are unplugged). Using a resistance bridge to drop the mains voltage to less than 5V gave me a signal without the glitches ( with and without the powerline plugged into the mains). Glitches appear as intermittent large pulse on the output of the module, thinking about it the module may be outputting its maximum possible output voltage for 20-25% of the mains cycle. Appears to be a somewhat random but frequent glitch appearing at various places in the mains cycle.
I plan to reuse the transformer off the unit and use it in one of the simpler circuits published on this web site.
Anyone seen anything like this associated with Powerline Networking?