Replacement tube for IBM 026 Printing Card Punch

--- John Lawson <jpl15(a)panix.com> wrote: A follow-up: Looking at the notes on the "IBM Wiring Diagram", number 228005-5, E.C. #203242, "Machine - Printing Card Punch, Model 026" which I found in the base of mine, there are notes on the 4th leaf (it's one long folded sheet) in Roman Numerals: X All tubes are 25L6's XI All bias resistors are 56K, .5W, part no. 301149 All screen resistors are 4.7K, 1W, part no 169129 unless otherwise noted All grid protection resistors are 10K, 1W part no 184093 XII Tube #8 and relay 53 are used only on machines with comb. keyboards XIII ----- - - ------ indicates wiring when comb. keyboard used XIV -- -- -- -- -- indicates wiring when num. keyboard used XV =====o===== indicates solid bar common XVI The marked NC terminal on the switch is the terminal wired as shown XVII Resistor common not wired as shown A couple of things: it explicitly says all tubes are "25L6" and that only tube 8 is optional, depending on configuration. From looking at the rest of the wiring chart, I can see all the tubes in use except for 6, the one that Sellam seems to be missing. The tubes seem to drive various relays thusly: 1 Escape Interlock 2 Release(?) 3 Escape Magnet 4 Skip 5 Dup 6 ? 7 Punch Clutch 8 Alpha Field (with comb. keyboard) 9 Print Sup Magnet 10 Print No mention of tube 6. :-( -ethan __________________________________________________ Do You Yahoo!? Yahoo! - Official partner of 2002 FIFA World Cup http://fifaworldcup.yahoo.com