Reproduction front panels and switch levers for PDP-8/E and M

On 03/09/2014 16:27, Jack Rubin wrote: [...] [...] There are also (at least) two variants of the 8/E panel screening. The early ones used a rotary switch with 36-degree spacing, so the highest position (STATE) and the lowest (BUS) are 180 degrees apart, and the lines for those are vertical. On this panel, there are no vertical white lines between the octal groups, and if you look closely you'll see that there is no gap between the EMA section and the rest of the MEMORY ADDRESS legend. The darker orange colouring is also slightly brighter (or less dull) than on later panels. The early panels often had an octal listing of the RIM loader on the right, above the HALT/SING_STEP/DEP switches, but that's a glued-on plaque, not part of the silkscreen. The later panels were redesigned to accommodate a more conventional rotary switch with 30-degree spacing (so like a 12-position switch instead of a 10-position one) and the lines from the highest and lowest positions are not vertical; they're 15 degrees to the left. There are five vertical white lines between the MEMORY ADDRESS legend and the 0-11 positions below, separating the two rows of lamps into four groups of three (octal numbers). There's a small gap between the EMA section and the rest of the MEMORY ADDRESS legend, and the darker orange colour is a little duller (might just be batch variation, though). I don't recall ever seeing a RIM Loader listing on one of these, but I might not have paid enough attention to every one I've seen so don't quote me on that part :-) None of the 8/E panels I've seen have a red wash for the lamp positions, just a little frosting. I've seen a reference to the rotary switch change and the angles in one of the DEC manuals or maybe an ECO, but can't see it just at the moment. I've a picture showing both panels (er, machines!) side by side at https://www.flickr.com/photos/pnt103/9365750952/ -- Pete Peter Turnbull Network Manager University of York