View Full Version : Osborne 1 and Osborne Executive found on Craigs List

January 26th, 2013, 10:41 AM
I found these two Osbornes on Craigs List in Destin, Fl. Both appear to be work somewhat, the display on the executive does not work. I connected a monitor and it displayed a prompt screen. Neither machine would read the CP/M boot disk but both drive lights came on and I could hear the diskette spinning. I have not had time to properly clean the drive heads.

The computers came with an external Zenith monitor shown in one of the pics attached. Over 70 floppy disks were included as well as 3 diskette trays. CP/M Version 3.0 and UCSD p-system were both included as well as Wordstar and SuperCalc.

I guess findind a display replacement or parts for these would be close to impossible, but for $25.00 they seemed like a bargain.


The diskettes include in the OSborne approved software binder were
CP/M Plus Version 3.0 disks 1 - 3
MBasic/CBasis Version 5.21/2.38
Wordstar Version 2.0 and 3.30
SuperCalc Versions 1.00 and 1.12
Personal Pearl Version 1.06 disks 1 - 6
UCSD p-System Version IV.12.B

January 26th, 2013, 10:54 AM
Didn't it need some kind of jumper for the internal display? Maybe there's something useful in this thread:


Good Luck!!!

January 26th, 2013, 11:52 AM

I spent a little more time with the Osborne 1. I had it on for about a minute and was going to try and clean the drives. I started to get a hot smell and turned it off immediatly. I have not had a chance to disassemble it and do a visual inspection but I suspect a display component. The display was still visable when I turned if off.

I know I am going to need some help with this one. It's my first Osborne, but I am looking forward to trying to get it back in working order.


January 27th, 2013, 03:03 PM
I spent some time with the Osbornes this afternoon, not Ozzie but the Executive. I have a display and the prompt screen but when I press the enter key, Drive A spins but the head does not move. I know nothing about an Osborne, but I did see the floppy cable is attached to the motherboard.

Any suggestions or help would be greatly appreciated.



Old Computers
January 27th, 2013, 03:08 PM
I don't know too much about Osborne's drives, but it sounds like the drive mechanics need to be lubricated.

January 30th, 2013, 09:19 AM
The drives get their power from the data cable, these are modified drives, you can't just pop in a drive from an IBM PC or something.

January 30th, 2013, 01:21 PM

I have disassembled the executive and taken several pictures. This is my first experience with an Osborne so I am following the Hippocratic Oath (first do no harm). Pretty interesting setup. As I mentioned, the drives spin but does not boot. I am going to clean the drives and see about making a new boot disk. I hope Dave's Image Disk will do the trick, I do have a couple of Single Density Single Sided disks.



January 30th, 2013, 02:30 PM
I was referring to the Osborne I drives. I only have the original unit model.

February 6th, 2013, 01:54 PM
There is a little "dongle" on an Osborne 1 located on the right side just to the left of the reset switch, it says:
For some reason these are frequently missing. I seem to recall that the internal monitor will not work without that "dongle" in place
If yours is missing I'll comb my junk pile, I may have an extra one for trade or whatever.

February 6th, 2013, 02:04 PM

Yes it is thanks, Mike mentioned in an earlier post that there may be jumper setting that needs tobe changed, but I did not find which jumper.

I have not had a lot of time to spend working in it, but I am looking foward to trying and getting it running again. I did find some parts from a member here.



February 21st, 2013, 11:11 PM
We have managed to accumulate 5 of the Osbornes, 4 are the Osborne 1 and one is the slightly later and nicer two-tone Blue version.

We have a load of disks and one or two manuals, and we are in the UK.

Amazing what you collect over the years.... :D

The blue one my wife looked at in a surplus shop in the Surbiton area, that was fully functional, as was the second one we bought.

The last three were a job lot we picked up near Manchester.


February 22nd, 2013, 04:36 AM

Yes it is thanks, Mike mentioned in an earlier post that there may be jumper setting that needs tobe changed, but I did not find which jumper.


March 14th, 2013, 01:36 PM
Ok, the Osborne 1 is up and running, thanks to a member here having some spare parts. Super Calc is the bomb.

Now to tackle the executive.




April 5th, 2013, 11:22 AM
Jimmy, if you need a hand with that Exec, let me know. Sounds like you already have all the system software (the CP/M 3 disks are for the exec) but I could probably help you get it online enough to pull software down from the archives, if necessary.

April 5th, 2013, 11:44 AM
I apprecaite it. I have not had any success gettting it to boot. I am not sure if I do not have the drives jumpered correctly, have a bad drive, bad disks or bad disk controller.

Any information or help would be be fantastic.


April 5th, 2013, 12:17 PM
What state is it in at this point? I assume the mechanisms have been cleaned and lubricated at this point? Typically - the Exec should give you an error if you attempt to boot it without any floppy at all, is it giving you the boot failure message either with or without a floppy inserted?

The CP/M 3 disks should be for the exec- but it definitely will not boot anything from a Single-Density Osborne 1. If you suspect the disks themselves may be the problem, and if you have a way to write floppy images from a PC, I have 3 known-working Executive CP/M 3 teledisk images I could send you.

May 7th, 2014, 02:29 PM
I just added an Executive to my (now 3) unit Osborne collection. Screen works fine, passes all diagnostics, but won't boot from (known good) CPM 2.2 O1 SSDD boot disk. Regarding the drives, I was able to use Executive part (starts about p. 165) of the Service Manual I found on: http://bitsavers.trailing-edge.com/pdf/osborne/2F00040-00_Service2ndEdition_1983.pdf

I'm pretty sure the config was stock:
'A' drive on the top, 'B' on the bottom (wish I knew how to make it try to boot from B like Shift+" on the O1)
A drive has a terminator installed in a DIP socket, B does not.
Data cable goes to Drive B first, then ends at Drive A (hence the terminator)
A has little blue jumper on DS1 (not marked, but just above DS2)
B has little blue jumper on DS2 (just above DS3)
Drives seem fairly standard (Data connector and separate molex power connector)

I found that the head carriages for both Alps drives were very 'stuck'. There are two rails along the sides of the heads that need to be cleaned (with isopropyl alcohol), and then lubricated (with silicon grease). Of course, you also need to do a thorough head cleaning (I'm amazed that I saved a few 5.25" head cleaning disks).

So after all of that, I have one drive that always reports 'BOOT ERROR' (as if the disk wasn't even there) when Drive 'A', and the other that starts 'LOADING', and then detects an error. I'm afraid that I'm going to have to get out my O'Scope and do some serious calibrating.

I'm going to fire up Dave's IMD and burn an original Exec boot disk and see what happens...

May 7th, 2014, 03:54 PM
Follow-up to my post from earlier today. I used IMD to create a bootable floppy from an old PC with a nicely cleaned and calibrated TEAC 360K floppy drive.
I used the Osborne Exec files from http://www.classiccmp.org/dunfield/img54306/system.htm and cut CPMPLUS1.IMD. I set it for 40 cyls, and double-step off. The original 'A' drive would not boot it but after I swapped the original 'B' drive into the 'A' spot, it booted reliably from the new 'A'. I tried to format a new disk in the (now) 'B' drive, and it posted an error for every cylinder.
Looks like I'm in the market for a replacement Alps drive or equivalent... The interface seems standard (34 pin keyed data connector, standard looking molex power), so I may just try a 360K drive. Or I might even try a 3.5" floppy as the B drive if I can find one I can set to DS2.
For now, I'm going to replace the 0.1uf cap in the power supply before it smokes (both my O1s have blown them).
Good Luck with your Exec if you're still playing with it.