Are you sure of that? Unless the floating point chip (and socket) on an KDJ11-A or -B is identical to the one which is used on the KDF11-A and -B (and I don't think they are identical, since the one for the KDF is a dual chip carrier), it won't work. The FPF11 board has a ribbon cable which ends in a connector which fits the Floating point chip socket of a 11/23, 11/23+ and 11/24. Megan Gentry Former RT-11 Developer +--------------------------------+-------------------------------------+ | Megan Gentry, EMT/B, PP-ASEL | Internet (work): gentry!zk3.dec.com | | Unix Support Engineering Group | (home): mbg!world.std.com | | Compaq Computer Corporation | addresses need '@' in place of '!' | | 110 Spitbrook Rd. ZK03-2/T43 | URL: http://world.std.com/~mbg/ | | Nashua, NH 03062 | "pdp-11 programmer - some assembler | | (603) 884 1055 | required." - mbg | +--------------------------------+-------------------------------------+