pdh,Marc,
Thanks a lot for your thoughts on this.
Come to think of it pdh, I reckon that the EMI from my Computer PSU, could be the result of buying a cheapo PSU (as in lack of sheilding).
I've been doing a fair bit of reading up on the subject of the SMPS in the last week or so and as far as I can tell, a good SMPS should not cause any problems due to it's operation at all.
I guess that you get what you pay for in this respect.
They even make SMPS units to power Ham gear here, so I have no idea what I'm talking about!. [Linked Image]

de ZL3TPQ