"pfm"

Thanks all for replies. Please google for 'Fundamentals of Floating
Measurements and Isolated Input Oscilloscopes'. This is a Tektronix
application note. The situation to which I refer is is at the bottom
of page 4.

** The warning is about the potential for a FATAL ELECTRIC SHOCK !

http://www2.tek.com/cmsreplive/tirep...18312_EN.p df


I want to use an oscilloscope to check the PWM switching
chip on the primary side of an SMPS.


** The Iso Tranny goes with the SMPS - you fool.



.... Phil