Thanks for the first ever portable computer, its in good condition
Heres what I have found....
I have taken it apart and cleaned the disk drive R/W heads with I.P.A. this has restored drive 1 back to perfect function,
Formatted a couple of spare disks so Drive 1 is reading and writing faultlessly.
Drive 2 is not responding to track change signals but the spindle powers on / off at correct times
obviously a faulty drive controller board on drive 2
So I can run any of the software, but cannot backup any floppies since this requires both drives A & B'
Still the screen is very clear, and its complete with two boxes of disks and the user manuals, the handle and clips are not broken,
the cord for the keyboard is not stretched, and it was surprisingly dust free and clean on the inside.
Every disk is loading now without load errors, even though they are a bit on the "dry" side of things
It has the duel density upgrade and I found the software disk for it, this allows these formats:
•Osborne 1 single density - 92K per diskette
•Osborne 1 double density - 182K per diskette
•Xerox 820 single density - 82K per diskette
•Cromemco single density - 80K per diskette
•IBM Personal Computer (CP/M-86 format) - 156K per diskette
•DEC VT-180 - 171K per diskette
It also has the composite video socket on the front for external green screen.
Appearantly its a revision F motherboard.