For the 85, at least, the answer is yes. The 86 backup format isn't actually compatible with the 85 as was first claimed by TI. Besides, ZShell doesn't work on the 86. >My friend somehow lost the zshell command from the custom menu, >when I tried doing a memory bkup on my 86 I got transmission error? >does anyone know, can you only do backups onto another calc of same type; ie, >85>85? >thanks, >Jake