This is a computer I rescued from a skip many years ago.
It is a model PC100-A with a single dual floppy and the memory expansion installed, with a date of manufacture on the case of 31 5 83
It has the original keyboard, but for some reason I don't seem to have the monitor. It has been in storage for over 20 years, I can't remember if I ever had it. It has a complete CPM 86/80, User Kit and Spellstar software and manuals. The lack of monitor initially posed a problem as the keyboard connects to the monitor, but some research revealed it can run an external video monitor and the keyboard with an adapter, which I have constructed from junk box bits in order to test it.
After some preliminary heath checks befor applying mains power, it powered up successfully, but the self test fails with a "MAIN BOARD - Z80 CRC - ERROR 18".
There is plenty of information and software available for these on vintage computer sites, except for the one thing that I may need to fix it. That is the rom image files for the A model, which would verify that the error isn't a bad eprom, so for now, it is back in the "needs attention" queue.
My Osbourne 1 technical manual includes rom listings, but they aren't included in the technical manuals for the Rainbow
Update: with the help of another Dec Rainbow fan, I have been able to get a rom dump which has confirmed the eproms are valid so I'm now able to move on an check other options