I found a vintage rackable linear PSU at a sale over the weekend, appears to be late '70s vintage going by date codes on some of the high-power components inside. Front panel is plain black with just a power switch and telltale lamp. Back has a ratings sticker which says "PPI 1247-000-91 ADDS". Outputs are +24V at 3A, +12V at 2A, +5V at 30A, -12V at 4A. Ring a bell with anyone? I'm familiar with ADDS in a terminal context, of course, but this lump is obviously for something larger - perhaps a "washing machine size" fixed/removable drive unit or similar, but I'm surprised there's not obvious branding on it if so. cheers Jules