(22 Jan 2014, 6:03 pm)mattdw92 wrote The trial is to do with the fact white on black apparently is better for those with sight disabilities. Yellow is much more attention grabbing and piercing, unlike the white - especially when bright light hits the front in instances of full sun, which is true to Lothian's Tridents with white blinds. Surprised it got past the HO testing stage.
If you are talking about HO as in Bensham, it is us who asked Hanover for it as we want to compare the amber LED's versus white (remember white on black is used in London now and Hanover have even provided a white LED blind to the Citaro K demonstrator). We do not use yellow LED's.