On 4/28/19 3:55 PM, Ray Jewhurst via cctalk wrote: Hi Ray, about 18 months ago, I did indeed install VMS 1.5 on a simulated (with simh) VAX-11/780. It was not particularly difficult, but it did take a bit more effort than I expected. Here is what I did and the problems that I came across. I am typing this from memory, so I might have mis-remembered the odd fact. The instructions tell you to create a bootable disk from tape using the DSC utility. However, DSC was something that ran in PDP-11 emulation mode on a VAX and was discontinued early enough in the evolution of VMS that it was not present on any of my simulated systems (VMS 4.x, 5.x and 7.3). I needed to build a VMS 3.0 system in order to complete copying the VMS 1.5 tape to disk. If you have a simulated PDP-11 system, you might be able to use that instead. Building the VMS 3.0 system gave me another problem in that I tried using a simulated TE16 (Massbus) tape drive to read the VMS 3.0 installation tape. This should have been fine, but actually I uncovered a bug in simh. Bob Supnik fixed the bug, but you do need to use an up to date version of simh to get the bug fix. If you need to use an old version of simh for some reason, then use a TS (Unibus) tape drive and all should be well. VMS 1.5 is primitive compared with later versions, but does have historical interest. Do let me know if you want any further information about my adventures with VMS 1.5. Cheers Peter Allan