Hi friends,

I have a funny problem. We had supplied a PC based data acquistion system, and had a problem of random freezing of the PC. And just as a trial I brought in a mains surge suppressor + EMI filter combo for PC power and not surprisingly for the last few weeks the problem has completely vanished. But customers are customers and I have been asked to give documentary proof / demonstrate that mains borne noise was the issue to start with. ( final payment on hold due to this !)

What I want to know is this: Can I rig up a step down transformer, say 230/24V and connect an oscilloscope( I have a 20Mhz one ) to the secondary. Now in the same mains socket I create 'noise' by having a CF lamp and switch it on/off by touching the lead wires instead of a switch.

If i now monitor the waveform from the secondary with and without the EMI filter, can I see some difference ? Of course I am aware this method is rather crude but then my business is not validating EMI filters !!

Any better ideas in this regard ??

Thanks

Raghu