Hi again all. The teledisk images have 16 sectors per track this makes them 360K. This makes them DD (Double Density) which is why I could write them on a PC with a 1.2MB drive.
The Micropolis 1015-5 in The OC-8880 is a QD 400K it seems to spin at 300 RPM but should have 20 sectors per track and 80 tracks. I thought 5,25" QD would rotate at 360 RPM similar to 8" so clock would be double of DD. I don''t know if it has two speeds and actually boots at DD and 300 RPM but can also do 360 RPM and QD.
I wonder if QD would be similar to HD and use a significantly higher current to write (bias) like PC 1.2MB does.
I will proceed to look at the floppies on another computer to see if there is anything sensible there. Also check frequencies on FDC and CPU to see if that makes sense.
The drive seems OK, though rotating speed may be a little off, if other things are OK I will try to adjust that.

I tried the TeleDisk images Alejandro Daniel Perez found. Unfortunately no success yet.

I created real media with ms-dos on a 1.2MB 5.25" drive (has 80 track) and used DD 360K media, though it is not certified for 80 track. This seemed to go well, so far so good.

The OC-8880 did respond with some more messages so it was trying. Loading, but didn''t like the floppy. From the sounds the drive may be bad.

I will try to find out if the floppies are ok on a different old computer. I will try to find out if the drive is bad, if it is an 80 track drive etc. In 1981/1982 80 track wasn''t that common. Two years later it was pretty common.

BTW I will try mesuring what frequency the CPU has, and confirm if signals match Z80.

Hi everyone! I believe that I have found a disk image to check with this computer here: http://www.retroarchive.org/maslin/disks/misc/index.html

The image name is monroe.td0 and monroe88.tdo, if anyone can check it I would like to know if the images are working fine. I have a Monroe OC-8820 but it still under repair