On 2018-Sep-23, at 7:46 AM, Michael Thompson via cctech wrote: > Visitors to the RICM like to play SPACEWAR! in the PDP-12. Unfortunately > using the console switches is uncomfortable, not intuitive, and is tough on > the switches. We would like to recreate the switch boxes used on the PDP-1 > to make playing a better experience. > > We modified the source > <http://www.ricomputermuseum.org/Home/equipment/dec-pdp-12/dec-pdp-12-source-code/SPCWR3.12?attredirects=0&d=1> > from D.E. WREGE > <http://www.pdp8.net/pdp8cgi/os8_html/SPCWR3.PA?act=file;fn=images/jby/jbyos8.tu56;to=ascii;blk=510,131,0;plain=1> > to use the LINC SXL instruction to read the PDP-12 GPIO signals, and > prototyped two switch boxes using recycled toggle switches. This works > great, so now we need to make better switch boxes. > > This CHM article shows what we want to recreate. > <http://www.computerhistory.org/pdp-1/a87ddd9510aeebf6485c47a35f8a26aa/> > This article shows a sketch of the switch boxes. > <http://thedoteaters.com/?attachment_id=6416> > A generous donor made these boxes for us. > <https://scontent.fbos1-1.fna.fbcdn.net/v/t1.0-9/37971884_2342940525721951_2976743744394493952_o.jpg?_nc_cat=0&oh=5b1e1cc3336ad56b854294f285834197&oe=5BF21887> > > The lever switches are turning our to be difficult to find at a reasonable > price. We found some NOS SwitchCraft lever switches that looked like the > sketch and the PDP-1 pictures and were a reasonable price, but our order > was rejected because they only had one in stock. eBay has Mossman and > SwitchCraft, but they are either very expensive (more than $50 each), or > they only have one available. > > The switches that we are looking for need to be SPDT, three-position, > non-locking, center off. (If the switches have more than one pole we can > remove the extra poles to keep the operational force low.) Before we cave > in and buy some modern C&K toggle switches, does anyone have a source for > Mossman or SwitchCraft switches at a reasonable price?
You haven't provided much detail about what limits you're willing to entertain in style of switch. There are a wide variety of lever switches available. There are leaf-contact switches that mount with two screws and a slot for the lever, leaf-contact with a throated actuator that mount in a 1/2 inch hole (much easier to mount than making a narrow slot), wafer switches with the two-screw/slot mount, etc. Slot-styles may have the lever plane made from stamped/sheet metal with a slide on knob vs. made from thick ~3/16-1/8 inch metal with a thread-on knob. The latter were very robust and the type typically found in telephone switchboards, although there were also some cheaper japanese makes. Do you want period-correct even if not the exact manuf/type originally used, or when you mention C&K are you referring to modern mini-toggles as acceptable?