As you say Phil, it's crazy that they omit the filtering components that there is space for on the PCB, just to save a few pence. (they often do the same in small chargers too - but not on the better ones)
Personally, I would have accepted the offer of a replacement PSU, as filtering it on the Mains input is not the best way to do it if it's noisy to start with. When the PSU packed up in one of my 5 PCs I have here, I went to a local shop who sold them for £10 (crazy price!) . . . but I asked to open it up to make sure the filtering components were there . . . they were, so I bought it. The biggest problem with Top Band Noise here in Britain is NOT noisy switch-mode PSUs . . . it's the fact that 90% of the Internet Broadband is delivered via overhead copper telephone wires. These radiate the hash for miles, as I'm sure you can imagine. I'm luckier than most, in that the phone wires in my street are underground (being a new street). So I don't have an S9 +10dB noise level like most locals. However, there are dozens of overhead phone cables at the end of my street, just 300 feet away. So apologies if I have trouble hearing weak signals calling me . . . I do the best I can in an ordinary suburban location ! 73 Roger G3YRO _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector