Determining input voltage for switchmode PSU

Hi, This isn't specifically classic, but maybe someone can help. I have a SCSI optical drive mounted in an external case, made in 1992. There are no labels on the case at all. I was sent this from the United States (where mains voltage is 110VAC); I'm in the UK (where mains is 240VAC). Whilst I can use this unit in conjunction with a step-down transformer, is there any "rule of thumb" method for determining whether a switchmode PSU is auto-ranging? Rather than just connecting the unit up to 240V and risking damaging the PSU, I'd like some idea of whether it is designed to run from 240V. The fuse on the power supply PCB is 2A 250V, if that's any indication. There is no obvious wire link that could be moved to select between 110V and 220V operation. A label on the PSU reads MODEL NO. SP35W2P-141 There is also a logo which looks something like this: | | __ | / \__|___ | \__ That is, the letters L and E joined together. Any idea which manufacturer this is? -- Mark